by otto van der brug u.s. geological survey … resources of the yap islands by otto van der brug...
TRANSCRIPT
WATER RESOURCES OF THE YAP ISLANDS
By Otto van der Brug
U.S. GEOLOGICAL SURVEY
Water-Resources Investigations Report 82-357
Prepared in cooperation with the
TRUST TERRITORY OF THE PACIFIC ISLANDS and the
STATE OF YAP, FEDERATED STATES OF MICRONESIA
Honolulu, Hawa i i
1983
UNITED STATES DEPARTMENT OF THE INTERIOR
JAMES G. WATT, Secretary
GEOLOGICAL SURVEY
Dallas L. Peck, Director
For additional information
write to:
District Chief
U.S. Geological Survey, WRD
Room 6110, 300 Ala Moana Blvd.
Honolulu, Hawaii 96850
Copies of this report
may be purchased from:
Open-File Services Section
Western Distribution Branch
U.S. Geological Survey
Box 25^25, Federal Center
Denver, Colorado 80225
(Telephone: [303] 23^-5888)
CONTENTS
Page
Abstract 1
Introduction 2
Cooperation 2
Purpose and scope - - ----- - -- 2
Geographic setting ------- - - -- -- - - - 3
Hi story ------ --- - _______ _ _ __ ___ 3
Population _____ ____ _ _ _ ____ _ 5
Previous investigations - - --- ----- - - - - - 5
Acknowledgments - - 6
Cl imate --------- - __________ __________ _______ _ __ 7
General - ------------------ - -- --- ____ _ _ ____ 7
Rainfal1 7
Evaporation - - -- - 9
Air temperatures ---------- - --- -- ____________________ ___ 10
Geology 13
Descriptive geology -------- --- --- -- __________ _ _____ 13
Water-bearing characteristics -- ---------- --- - ________ 16
Water resources ----------- _--_-_-___-_-__ _________ ______________ 17
General 17
Surface water -- ---- ------ ____ __ ______ __ - _ 20
General 20
Streamflow characteristics - - 24
Rainfal1-runoff relations ---- - ------ -- - ----- 24
Flow-duration curves ----------------------------------- 27
Low-flow frequency tables ----------------------- ----- 29
High-flow frequency curves - --------------- ______-_- 29
Correlation of partial record with continuous record - ----- 38
Historical and existing developments ---- ----------- ----- 38
Ground water -- - -- - 49
Historical developments ----------- _--__--____-___-_----- 49
Nature and occurrence ---------------------- ------------- 51
i i i
CONTENTS
Page Water quality -- ------- ------- _______ ------- ---------- 58
General --- - -- 58
Chemical analyses ---- -------------------------- ___ 59
Water temperatures -- ------------------- _______________ £5
Application of data for future water development ----------- ------- ££
Reservei rs - ---- ------ _________________________ ________ 55
Rain catchments ------- -------------------------------- __ _-_ 72
Summary ---- - -------- - -------- --___--______ _-__ ____ 79
Hydrologic data - ----- -- ----------- -------- ------- 80
Rainfal 1 84
Evaporation -------------- --------- ----------------- ___ - 93
Air temperatures ------ --------------------------- ---------- 94
Streamflow records - - - ------ ------------------------ 95
Gaging stations -- - ---- --- ---- ---------------- 95
Low-flow partial-record stations ----- --- ---------------- ^32
Miscellaneous measurements -- ------------------------- 143
Water quality - ---- -- 144
Chemical analyses ----- - - - -------- - - --- 144
Water temperatures ----- ----------- ____ - __ ----- ^57
References ------------- - ------------------ ___________________ 185
i v
ILLUSTRATIONS
Figure Page
1. Map showing the location of the Yap Islands - 42. Map showing the location of rain gages -------- -------------- ]]
3. Graph showing Yap rainfall, temperature, andGuam evaporation, 1956-80 - 12
4. Map showing geology of the Yap Islands - ----------------- -- 14
5. Map showing the location of surface-water data-collection sites 18
6. Photograph of gaging station on Mukong Stream, Gagil-Tamil 19
7. Photograph of gaging station on Qaringeel Stream, Yap ------- 19
8. Graph showing flow-duration curves of four streams onYap Island and one on Gagil-Tamil -------- ____ ______ 28
9.-13. Graphs showing magnitudes and frequencies of
highest mean discharges for duration indicated for
the following streams:9. Qaringeel Stream, Yap 32
10. Daloelaeb Stream, Yap 33
11. Peemgoy Stream, Yap - - -- 34
12. Taalgum Stream, Yap - ------------- _____________ 35
13. Burong Stream, Yap - - --- 36
14. Graph showing magnitude and frequency of annual and
instantaneous peak flows for four continuous-record stations on Yap Island, 1969-79 37
15.-19. Graphs showing correlations between discharges at
following locations:
15. Tamaney and Qaringeel Streams - - - - - 40
16. Ripu and Qaringeel Streams - - --- - 41
17. Tholomar and Qaringeel Streams -- -- 42
18. Maabuuq and Peemgoy Streams - - 4319. Gilaew Stream and Gilaew Spring --------- -- ------ 44
20. Photograph of Airport swamp with wreck of
Japanese fighter plane ------ ____________ __- ______ 45
21. Photograph of 25-Mgal (upper) reservoir at Gitaem, Yap - 47
22. Photograph of 2-Mgal (lower) reservoir at Gitaem, Yap - 47
23. Photograph of treatment plant at Gitaem, Yap - - --- 47
ILLUSTRATIONS
Figure Page24. Map showing the Colonia central water system ------------------ 48
25. Map showing the location of wells and springon Gagi1-Tamil and southern Yap, 1971 ----- ____-__-_ 52
26. Map showing the location of wells drilled in 1979 and 1982 55
27. Map showing the location of sites where chemicalanalyses of water were made ----- ------------- _____ _ 60
28. Map of south central Yap Island showing possible dam sites - 67
29.-31. Graphs showing mass curves of mean monthly discharge
values of the following locations:29. Daloelaeb Stream, Yap - 69
30. Peemgoy Stream, Yap ---- --- ------ -- -- 70
31. Taalgum Stream, Yap - ---- --- -- - -- - 71
32.-35. Graphs showing daily draft rates and storage requirements for
rainfall catchments in Yap Islands for the dry period:
32. In a year with average rainfall (1960) - - 74
33- In a year with average rainfall (1965) -------------- 7534. In a very dry year (1966) -- --- --- - - 76
35. In a very dry year (1973) -- ~ - ---- - 77
VI
TABLES
Table Page
1. Long-term means, minimums and maximums of rainfall
at or near Colonia during period 1901-82 82. Rainfall records of the Yap Islands 10
3- Surface-water stations in the Yap Islands -- - --- 21
4. Mean monthly discharge, monthly percentage of annual means,and percent of no-flow days - - - - 23
5. Annual rainfall-runoff comparison, 1969-81 25
6. Rainfall-runoff comparison for June to December 1969-81 26
7. Lowest mean value for a number of consecutive days foryears ending September 30 30
8. Correlation between discharges at low-flow partial- record and continuous-record stations 39
9' Results of chemical and microbiological analyses on six
grab samples from the Colonia water-distribution system 50
10. Partial chemical analyses of water samples taken January 1971 - 53
11. Depth to water of wells on Yap and Gagil-Tamil 57
12. Chemical analyses of water from the Spanish well (1952) 61
13. Chemical analyses reported by Austin, Smithand Associates (1967) 62
14. Chemical analyses made for Lyon Associates (1979) 63
15.-16. Draft rates for available storage for several catchment sizes:
15. During the dry period of years with average rainfall 7816. During very dry years - - -- - 78
17--19. Monthly and annual rainfall:
17. During the German Administration 8^
18. During the Japanese Administration -- - - 8519. For the period 19^8-83 86
VI I
TABLES
Table Page
20. Mean monthly rainfall for a period of 27-28 years prior to 1938 8?
21. Monthly and annual rainfall at Gagil-Tamil, 1969-73, 1976 87
22.-23- Cumulative rainfall readings:
22. At Protestant Mission, Colonia, Yap 8823. Near Taalgum Stream, Yap -- -- -- - 89
24. Daily rainfall at continuous-record rain gageat LORAN station, Gagil-Tamil 91
25. Monthly and annual evaporation data for Guam and Yap ------ 93
26. Monthly and annual mean air temperatures for Yap (1921-50) - - 9^
27. Monthly and annual mean air temperatures for Yap (1951-81) -- 95
28. Streamflow records of Qatliw Stream, Yap:A. Discharge measurements -------------- ------- ______ 9$
B. Monthly discharge 97
29. Streamflow records of Qaringeel Stream, Yap:
A. Annual maximum discharge and peakdischarges above base - - 99
B. Annual minimum discharge ---------- _______________ ]QO
C. Monthly and annual discharges - 101
30. Streamflow records of Daloelaeb Stream, Yap:
A. Annual maximum discharge and peakdischarges above base _-__--___-__---_--- -- 104
B. Annual minimum discharge ------ _-___-_______- ___ 105
C. Monthly and annual discharges ---- - --- ---------- 106
31. Streamflow records of Peemgoy Stream, Yap:
A. Annual maximum discharge and peakdischarges above base - 109
B. Annual minimum discharge - - 110
C. Monthly and annual discharges - 111
VI I I
TABLES
Table Page
32. Streamflow records of Taalgum Stream, Yap:
A. Discharge measurements made outside the periodof continuous discharge record -- ------------ 113
B. Annual maximum discharge and peakdischarges above base -- ---- -- --------- 114
C. Annual minimum discharge -- -------- -- ------- 115
D. Monthly and annual discharges ---- ------------ ---- 116
33. Streamflow records of Burong Stream, Yap:
A. Annual maximum discharge and peakdischarges above base -____----__-------- _-__ 119
B. Annual minimum discharge - 120
C. Monthly and annual discharges ----- -- ----------- 121
34. Streamflow records of Mukong Stream, Gagil-Tamil:
A. Discharge measurements made outside the periodof continuous discharge record - _____________ 124
B. Annual maximum discharge and peakdischarges above base --- ---------------- -- 125
C. Annual minimum discharge --- ____________ _-__ 125
D. Monthly and annual discharges -- ------------------ 126
35. Streamflow records of Gilaew Spring, Gagil-Tamil:
A. Discharge measurements made after the endof continuous discharge record - - ---------- 128
B. Monthly and annual discharges -- ---------- - --- 129
36. Streamflow records of Eyeb Stream, Gagil-Tamil:
A. Discharge measurements made outside the periodof continuous discharge record ----- ----- - - 130
B. Monthly discharge - - - - 131
IX
TABLES
Table Page
37--47- Discharge measurements of the following
swamp outlets and streams:37. Faraq Swamp outlets, Yap 132
38. Galngun Swamp outlet, Yap 133
39. Tamaney Stream, Yap - 134
40. Ripu Stream, Yap 135
41. Dhiaey Stream, Yap 136
42. Tholomar Stream, Yap 137
43. Mabuuq Stream, Yap 138
44. Monguch Stream, Gagil-Tamil 139
45. Gilaew Stream, Gagil-Tamil 140
46. Yanbilang Stream, Gagil-Tamil 141
47. Qamin Stream, Maap 142
48. Discharge measurements made at miscellaneous sites 143
49.-61. Chemical analyses of water from:
49. Qatl iw Stream, Yap 144
50. Qaringeel Stream, Yap 145
51. Daloelaeb Stream, Yap 146
52. Peemgoy Stream, Yap 147
53- Taalgum Stream, Yap 148
54. Burong Stream, Yap 149
55- Mukong Stream, Gagil-Tamil 150
56. Eyeb Stream, Gagil-Tamil --- -- - - 151
57- Low-flow partial-record stations on Yap - -- 152
58. Low-flow partial-record stations and miscellaneoussite on Gagil-Tamil and Maap 153
59. Airport Swamp and Water Treatment Plant, Yap 154
60. Wells on Yap and Gagil-Tamil 155
61. Airport and Tamil aquifers 156
TABLES
Table Page
62.-81. Water and air temperatures and instantaneous discharge at:
62. Qatl iw Stream, Yap 157
63. Qaringeel Stream, Yap 157
64. Faraq Swamp outlets, Yap 160
65. Galngun Swamp outlet, Yap - 160
66. Tamaney Stream, Yap - 161
67. Ripu Stream, Yap - - - 162
68. Dinaey Stream, Yap - 163
69. Tholomar Stream, Yap 164
70. Daloelaeb Stream, Yap 165
71. Peemgoy Stream, Yap -- - - -- - 167
72. Taalgum Stream, Yap -- -- -- - - - - 170
73. Mabuuq Stream, Yap - 172
74. Burong Stream, Yap - - 173
75. Monguch Stream, Gagil-Tamil 176
76. Mukong Stream, Gagil-Tamil - -- - -- 176
77. Gilaew Spring, Gagil-Tamil 180
78. Gilaew Stream, Gagil-Tamil 182
79. Yanbilang Stream, Gagil-Tamil -- - 183
80. Eyeb Stream, Gagil-Tamil - - -- - 184
81. Qamin Stream, Maap - -- - - 184
XI
CONVERSION TABLE
The following table may be used to convert measurements in the inch-pound
system to the International System of Units (SI).
Multiply To obtain
Lengthinch (in) 25.4 millimeter (mm)
foot (ft) 0.3048 meter (m)
mile (mi) 1.609 kilometer (km)
Area2 acre - 4,047 square meter (m )
2 2 square foot (ft ) - 0.0929 - square meter (m )2 2
square mile (mi ) --- - --- 2.590 square kilometer (km )
Volume
acre-foot (acre-ft) - 1,233 cubic meter (m )
cubic foot (ft3 ) 0.02832 cubic meter (m3 )
gallon (gal) 3-785 liter (L)
million gallons (Mgal) - - 3,785 - cubic meter (m )
Volume Per Unit Time (includes Flow)
cubic foot per second (ft /s) -- 0.02832 cubic meter per second (m /s)
cubic foot per second-day(ft^/s-d) 2,447 cubic meter (m^)
gallon per minute (gal/min) 0.06309 cubic decimeter per second (dm-Vs)
gallon per day (gal/d) - 90.85 -- cubic decimeter per second (dnr/s)
million gallons per day (Mgal/d) 0.04381 -- cubic meter per second (nr/s)
cubic foot per second per
square mile [(ft^/s)/mi 2 ]
micromho per centimeter at
25° Celsius (ymho/cm at 25°C)
Mi seellaneous
cubic meter per second per
0.01093 ---- square kilometer [(mVs)/km2 ]
microsiemens per centimeter at
1 25° Celsius (yS/cm at 25°C)
XI I
DEFINITION OF TERMS
Water Resources
Acre-foot (acre-ft) is the quantity of water required to cover one acre to a
depth of one foot and is equivalent to 43,560 cubic feet or 325,851 gallons.
Control designates a feature downstream from the gage that determines the stage-
discharge relation at the gage. This feature may be a natural constriction
of the channel, an artificial structure, or a uniform cross section over a
long reach of the channel. 3
Cubic foot per second (ft /s) is the rate of discharge representing a volume of
one cubic foot passing a given point during one second and is equivalent to
7.48 gallons per second or 448.8 gallons per minute.
Cubic foot per second day (ft /s-d) is the volume of water represented by a flow
of one cubic foot per second for 24 hours. It is equivalent to 86,400 cubic
feet, 1.93875 acre-feet, or 646,317 gallons.
D ischarge is the volume of water that passes a given point within a given period
of time.
Mean discharge (mean) is the arithmetic average of individual daily mean
discharges during a specified period.
Instantaneous discharge is the discharge at a particular instant of time. if
this discharge is reported instead of the daily mean, the heading of the
discharge column in the table is "Discharge."
Pi ssolved is that material in a representative water sample which passes through
a 0.45-ym membrane filter.
Drainage area of a stream at a specific location is that area, measured in a
horizontal plane, enclosed by a topographic divide fi-cm which a i reel
surface runoff from precipitation normally drains by gravity Into :he river
above the specified point.
Gage height is the water-surface elevation referred to some arbitrary gage datum.
Gaging station is a particular site on a stream where systematic observations of
hydrologic data are obtained.
XIII
Hardness of water is a physical-chemical characteristic that is commonly
recognized by the increased quantity of soap required to produce lather, due
mostly to the presence of alkaline earths (principally calcium and
magnesium) and is expressed as equivalent calcium carbonate (CaCO,).
Micrograms per liter (vig/L) is a unit expressing the concentration of chemical
constituents in solution as mass (micrograms) of solute per unit volume
(liter) of water. One thousand micrograms per liter is equivalent to one
mi 11igram per 1i ter.
Milligrams per 1i ter (mg/L) is a unit expressing the concentration of
chemical constituents in solution as mass (milligrams) of solute per unit
volume (liter) of water.
Partial-record station is a particular site where limited streamflow and/or
water-quality data are collected systematically over a period of years for
use in hydrologic analyses.
Runoff in inches shows the depth to which the drainage area would be covered if
all the runoff for a given time period were uniformly distributed on it.
Sediment is solid material that originates mostly from disintegrated rocks and is
transported by, suspended in, or deposited from water; it includes chemical
and biochemical precipitates and decomposed organic material, such as
humus. The quantity, characteristics, and cause of the occurrence of
sediment in streams are influenced by environmental factors. Some major
factors are degree of slope, length of slope, soil characteristics, land
usage, and quantity and intensity of precipitation.
Specific conductance is a measure of the ability of a water to conduct an
electrical current. It is expressed in micromhos per centimeter at 25 C.
Specific conductance is related to the type and concentration of ions in
solution and can be used for approximating the dissolved-solids content of
the water. Commonly, the concentration of dissolved solids (in milligrams
per liter) is about 65 percent of the specific conductance (in micromhos).
This relation is not constant from stream to stream, and it may vary in the
same source with changes in the composition of the water.
Stage is the water-surface altitude referred to some arbitrary gage datum (gage
height).
Stage-discharge relation is the relation between gage height (stage) and volume
of water per unit of time, flowing in a channel.
XIV
Streamflow is the discharge that occurs in a natural channel. Although the term
"discharge" can be applied to the flow of a canal, the word "streamflow"
uniquely describes the discharge in a surface stream course. The term
"streamflow" is more general than "runoff" as streamflow may be applied to
discharge whether or not it is affected by diversion or regulation.
Turbidi ty of a sample is the reduction of transparency due to the presence of
particulate matter. In this report it is expressed in Nephelometric
Turbidity Units (NTU).
Geology
Alluvium: Soil, sand, gravel, or similar material deposited by running water.
Amphiboli te: A granulose metamorphic rock consisting essentially of amphibole
and plagioclase, and commonly containing quartz, epidote, or garnet.
Basement rock: The assemblage of metamorphic and igneous rocks that underlie the
sedimentary and unmetamorphosed volcanic rocks in any particular region.
Brecc ia: A rock consisting of consolidated angular rock fragments larger than
sand grains.
Dike: A tabular body of igneous rock that cuts across the structure of adjacent
rocks or cuts massive rocks.
Facies: Designates the aspect or appearance of a mass of earth material
different in one or several respects from surrounding material.
Pault: A break or fracture in material of the earth's crust, along which there
has been movement.
Muck; Organic material which is decomposed enough so that identification of
plant parts is impossible.
Metamorphic rocks: Rock formed by recrystal1ization of an igneous or sedimentary
rock under the influence of heat, pressure, or both.
Schi st: A metamorphic rock that splits into thin, irregular plates because of
the presence of parallel grains of mica or other cleavable minerals.
Sill; A tabular body of igneous rock that has been injected, while molten,
between layers of sedimentary or igneous rock.
Tec ton ic; Pertaining to the rock structures and landforms resulting from
deformation of the earth's crust.
Tuff: Indurated pyroclastic rocks of grain generally finer than 4 mm (equivalent
to volcanic ash or dust).
xv
WATER RESOURCES OF THE YAP ISLANDS
By Otto van der Brug
ABSTRACT
The Yap Islands consist of four major islands, Yap, Gagil-Tamil, Maap, and
Rumung. Of these, Yap Island has more than half the total land area, most of the
population, and almost all of the economic development. The islands of Maap and
Rumung together compose only 15 percent of the land area and population.
Average annual rainfall over the Yap Islands amounts to 122 inches.
Rainfall-runoff comparisons indicate that about half of the annual rainfall runs
off to the ocean on Yap Island and Gagil-Tamil. Streams on Gagil-Tamil are
perennial but streams on Yap Island are dry an average of 3 month per year due to
geologic differences.
Analyses of water samples from 23 sources show the good quality and the
chemical similarity of surface and ground water.
This report summarizes the hydrologic data collected and provides inter
pretations that can be used by the planning and public works officials of Yap to
make decisions concerning development and management of their water resources.
INTRODUCTION
Cooperat ion
In 1968, the U.S. Geological Survey and the Trust Territory of the Pacific
Islands signed a joint funding agreement to systematically collect streamflow
data.
This program was expanded in 1972, with the addition of several rain gages,
and again in 197^, when a senior geologist, Dan Davis, was assigned nearly full-
time to Trust Territory Headquarters to provide advice on exploratory drilling
and ground-water development. The collection and analyses of water-quality data
were introduced into the program in 1979 with the collection of samples from most
streams on the Yap Islands.
Under the cooperative program, the Trust Territory Government agreed to
provide labor, equipment, services, and funds to be matched on an equal-value
basis by the Geological Survey. The Survey assumed the responsibility of super
vision, data compilation and analyses, and publication.
In 1981, after the formation of the Federated States of Micronesia, the
responsibility for the matching funds and services was transferred from the Trust
Territory Government to the separate states.
Purpose and Scope
The bulk of the hydrologic data collected by the Geological Survey since
1967 on the major islands in the Trust Territory of the Pacific Islands consists
of records of discharge and stage of most of the principal streams. More
recently, the data base has been expanded to include information on ground-water
resources, water quality, and rainfall. Most of the data have been published by
the Geological Survey in its annual release "Water Resources Data for Hawaii and
Other Pacific Areas," and for 1968-70 in Water-Supply Paper 2137. Miscellaneous
measurements made prior to 1968 were published in the 1968 annual report.
This report has two purposes: first, to provide a summary of available
water-resources information for the Yap Islands; and second, to provide in
terpretations that can be used by planning and public works officials of Yap to
make decisions on the future development and management of their water resources.
Geographic Setting
The Yap Islands are part of the Western Caroline Islands and lie between
9°27' and 9°38' N. latitude and 138°03' and 138°12' E. longitude, 450 miles
southwest of Guam, 1,100 miles east of Manila, 1,900 miles south of Tokyo, and
3,800 miles west of Honolulu (fig. 1).
The islands of Yap, Gagi1-Tami1, Maap, and Rumung are the four major islandso
and have a total land area of 38 mi (square miles). The smaller islands of Maap2 2 (4.1 mi ) and Rumung (1.6 mi ) are separated from Yap and Gagi1-Tamil by narrow,
shallow channels. Mangrove swamps border much of the shoreline, whereas the
i nter i or is mounta inous with forested val1eys and rol1 ing grass-covered hills. A
mountain range runs in a north-south direction along the eastern coasts and
averages about 600 feet in height on Yap Island and about 250 feet on the other
three islands. Plains are found at lower elevations in central Gagi1-Tami1 and
southern Yap.
Hi story
In 1525, the Portuguese Navigator, Diego de Rocha, was blown off course on a
trip from the Island of Celebes to Ternate Island. He spent some time on a large
island which, from his descriptions, could only have been Yap Island. The next
recorded western contact with Yap came 100 years later when a Dutch expedition
under Schapendam visited Yap and Ulithi, an atoll 106 miles east of the Yap
Islands (Fri is, 1967).
Although generally considered to be in the Spanish sphere of interest, Spain
showed little interest in the Caroline Islands until Germany tried to claim the
islands in 1885. This dispute between Spain and Germany was settled the
following year by Pope Leo XIII in favor of Spain.
Spanish rule ended in 1899 when Germany purchased the Caroline Islands. The
Germans were succeeded by the Japanese who occupied the Yap Islands in 1914 after
the outbreak of World War I. In 1920, Japan received a mandate from the League of
Nations to administer the islands. After withdrawing from the League in 1935,
Japan annexed the islands as part of its empire. At this time there were 392
Japanese on the Yap Islands (Great Britain Naval Intelligence Div., 1945). The
Japanese population grew rapidly with the influx of troops and the military
construct i on.
120 180° 150° 120°
I ! I0 1003 2000 3000 PCUOMtfESS
scAit AT EQUATOR
Note: Ail distances ere m statute miles 'one statute mile is 0 868 nculical mile 1
Figure 1. Location of the Yap Islands,
In 1945 after the end of World War II, Americans occupied the islands which
will remain under American Administration until their impending independence as
a state of the Federated States of Micronesia.
Populat ion
Nearly 8,000 people live in the islands, which is double the population of
25 years ago, according to Trust Territory statistics (U.S. Department of State,
annual reports). Since World War II, the yearly population increase has been 3
to 4 percent; practically all from births exceeding deaths. This increase
reversed a long period of population decrease, which began with the first
European contact.
In 1783, the population was estimated at 40,000, which appears exaggerated.
The estimate in 1862 was 10,000. During the German Administration (1899-1914),
84 inhabited villages were counted along with 150 deserted sites. The population
had decreased to 6,328 in 1910 and in 1935, only 3,713 were counted (Great
Britain Naval Intelligence Div. 1945).
Because of lower temperatures and traditional dependence on the sea for
subsistence, most of the population lives in villages scattered along the coast.
The only town on Yap is Colonia, the seat of Government during German, Japanese,
and American Administrations, and now, the capital of Yap State.
The economic base of the islands is narrow. Practically all employment is
with the Government in Colonia.
Previous Investigations
The earliest known reports on the Yap Islands were a petrographic study of
rocks by Erich Kaiser in 1901 (Kaiser, 1902) and a later one by Koert and Finckh
(Johnson and others, 1960).
The first geologic study was made during the Japanese Administration when a
map by Risaburo Tayama of the geology of Yap was published (Tayama, 1935). Since
World War II, several studies have been made by scientists from the U.S.
Geological Survey. Josiah Bridge participated in an economic survey of mineral
resources in 1946 (Bridge, 1946), and Charles G. Johnson worked on detailed
geologic mapping of Yap during 1947-48 and again in 1956 (Johnson and others,
1960). Arthur M. Piper wrote a report in 1947 titled, "Water Resources of Guam
and the ex-Japanese Mandated Islands in the Western Pacific."
A soil survey was made by Richard J. Alvis and Robert L. Hetzler in 1956-57
for the large volume, "Military Geology of Yap Islands," written by Messrs.
Johnson, Alvis, and Hetzler, with the exception of the weather and climate
sections.
Very little water-resources data had been collected prior to the start of
the cooperative U.S. Geological Survey-Trust Territory program in 1968 with the
exception of rainfall information, available for most years since 1900, which was
compiled for this report from several sources.
Acknowledgments
From the preliminary reconnaissance made by M. M. Miller in 1965 (written
communication, 1965) until the present time, the cooperation of the Headquarters
Staff of the Trust Territory of the Pacific Islands on Saipan and of officials in
the Yap District has been outstanding.
Special commendations are made to the following officials: Koichi L. Wong,
who has been involved in all phases of this work since 1965; Louis F. Irving, who
acted as liaison with Trust Territory Headquarters; the Yap District Directors of
Public Works, W. F. Dupont and M. Melarei; and those 1 i sted below who did most of
the data collection:
Mark Loochaz 1967-1969
Richard Mungwaath 1969-1970
George Giltharngan 1970-1971
Florentin Yangilmau (Palau) 1972
Hers Bosil 1973-1975
Adrian Gimed 1975-present.
CLIMATE
General
Because the Yap Islands lie near the Equator in an immense ocean, the
climate is generally warm and humid. Temperatures vary little, averaging about
27 C, with the difference between the means of the warmest and coolest month for
the period 1921-81 being only 2.6 C. From 19^9-81, the maximum temperature was
30.5 C and the minimum 24.1 C. Relative humidity averages 83 percent annually,
and is generally lowest in the afternoons between February and April and highest
in the early morning hours from June through December.
There are two principal seasons separated by short-duration transition
periods. December through April is the "dry" season, with predominant trade
winds from the east to northeast. July through October is the "wet" season,
characterized by heavy showers, occasional thunderstorms, west and southwesterly
winds interspersed with frequent periods of light winds and calms.
Typhoons on Yap are rare, as most pass well north of the islands in a
westerly direction. The worst typhoon known to strike Yap occurred on December
17, 1920, causing five deaths and the destruction of 1,330 houses from flooding
of coastal areas (Government of the Philippine Islands, Weather Bureau, December
1920). Maximum windspeed was estimated at 100 miles per hour. Other destructive
typhoons occurred in 1918 and on December 15, 1925, which, combined with a
tsunami, destroyed more than 90 percent of all houses.
Rainfall averages 122 inches per year, with monthly rainfall extremes
ranging from 0.2 inch for April 1926 to 45.9 inches for July 1911 (table 1).
Rainfal1
Although rainfal1 records for Yap, other than those at or near Colonia, are
of short duration or uncertain quality or both, they do show there is little
difference in annual rainfall throughout the Yap Islands.
Although rain showers often are localized, the relatively low profile of the
islands will cause these showers to occur at random, and thus are averaged in the
yearly total.
Table 1. Long-term means, minimums and maximums of rainfall,
In Inches, at or near Colonia dur ing
(No record available 1909, 1910,
Number of
years Mean
January
February
March
Apr! 1
May
June
July
August
September
October
November
December
Year
75
74
7374
75
75
75
75
7574
74
73
7.5
5.7
5.8
5.9
9.5
11.0
15.5
15.4
13.7
12.5
10.1
9.6
-/122.1
Percent
6.1
4.7
4.8
4.8
7.8
9.0
12.7
12.6
11.2
10.2
8.2
7.9
100
Minimum
monthly
^1.5
1/0.7
0.8
0.2
2.6
3.4
4.8
5.1
5.8
2.6
1.2
2.2
0.2
Year
1913
1915
1929
1926
1926
1913
1904
1973
1915
1976
1913
1928
1926
Maximum
monthly
23.1
22.6
17.1
18.2
19.3
32.0
45.9
32.1
28.2
24.0
22.5
23.1
45.9
per iod 1901-82
. 1944-48)
-/24-hour
Year
1955
1902
1911
1956
1928
1982
1911
1940
1904
1933
1924
1938
1911
maximum
10.45
5.94
5.09
6.57
10.06
13.17
9.92
7.57
8.35
5.32
8.91
5.61
13.17
Year
1958
1962
1963
1962
1967
1982
1911
1970
1978
1961
1960
1981
1982
-/ For period 1902-08, 1911, 1913-20, 1949-81.
2/ Rainfall for January 1983 was less: 1.25 inches.
- Rainfall for February 1983 was less: 0.27 Inches.
4/ Sum of 12 monthly means.
Cumulative rainfall readings at Geological Survey rain gages are of short
duration and because of vandalism and other problems, some readings were not
made. Some evaporation may have occurred between readings but data given in
tables 22 and 23 in the Hydrologic Data section correlate well with National
Weather Service records.
The available rainfall record of the U.S. Coast Guard LORAN station on
Gagil-Tamil for 1969-73, 1976 (table 21) compared well with the record of the
Weather Service station at Yap Airport (table 19) except for the 29-percent
difference shown by the 1970 totals. The LORAN station reading of 4.10 inches
for August 1970 appears to be inaccurate because streamflow records for Gilaew
Spring, Gagil-Tamil, for the month of August 1970 show the highest monthly
discharge of the year which is consistent with the Weather Service Yap Airport
rainfall total of 25.45 inches for the month. In December 1981, the U.S.
Geological Survey established a recording rain gage at about the same location as
the previous U.S. Coast Guard station (table 24).
Table 2 lists the locations and periods for which rainfall records have been
collected on the Yap Islands and figure 2 shows the location of these rain gages.
In the Hydrologic Data section, tables 17-19 list the monthly and annual totals
of rainfall records for most of the period 1900-1983.
Evaporat i on
Pan evaporation data for Yap are available from July 1978 to December 1982
and are summarized in table 25 in the Hydrologic Data section. Table 25 also
lists monthly pan evaporation data for the Island of Guam beginning in January
1956. The monthly values of the common period of record (July 1978 to
December 1982) are not well correlated; however, comparison of the evaporation
totals for the common period (53 months) is close (Guam is 8 percent higher).
Until the evaporation record for Yap is longer, the annual evaporation data from
Guam could be used to estimate the annual evaporation on Yap. Based on the data
compiled in table 25, the average annual evaporation for Guam for the period
January 1956 to December 1982 is 76.98 inches. This was determined by averaging
the monthly data and adding the means. Monthly records ranged between 24 and 26
years. For the short period of record on Yap, the total of monthly means is 75.15
i nches.
Figure 3 illustrates the seasonal relationship between rainfall, temper
ature, and evaporation (from Guam) for the Yap Islands.
Table 2. Rainfall records of the Yap Islands
Per iod
1899-1900 -
1901-14
1914-42
1948-51
1951-68
1968-83
1969-73,
1976
1974-79
1974-76,
1978
1981-83
Loca t i on
Rumung
Near present
Airport, Yap.
Meeth, Yap
(near Colon ia) .
Co Ionia
do.
Airport, Yap
Gagi 1
Taalgum, Yap
Colonia, Yap
Gagi 1
Lat i tude
north
9°37'
9°30'
9°30'
9°3T
9°3T
9°29'17"
9032'48M
9°31 '02"
9030'44"
9032'52M
Longi tude
east
138°09'
138°05'
138°08'
138°08'
138°08'
138005'04H
138°10'08"
138°06'33"
138007'29"
138°10'09"
Altitude
(ft)
170
30
114
53
53
44
75200
25
75
Source
German records.
Do.
Japanese records.
U.S. Navy.
U.S. Weather Service
Do.
U.S. Coast Guard.
USGS, cumulative.
Do.
USGS, continuous.
Air Temperatures
Monthly mean air temperatures for Yap for the period 1921-1981 are listed
in tables 26 and 27 in the Hydrologic Data section. From these data the
mean annual air temperature is 27.3 C. Other readings of air temperature
were made in conjunction with surface-water temperature readings during streamflow
measurements and can be found in tables 62-81 in the Hydrologic Data section.
10
138'05'E 138°10'E
RUMUNG ISLAND
MAAP ISLAND
GAGIL-TAMIL ISLAND
YAP ISLANDS
CONTOUR INTERVAL (APPROXIMATE) 10 AND 50 METERS DATUM IS MEAN SEA LEVEL
EXPLANATION
U.S. RAIN GAGES
APPROXIMATE LOCATION OF » GERMAN AND JAPANESE RAIN GAGES
U.S. WEATHER SERVICE RAIN GAGES
Base from U.S. Geological Survey Yap Islands 1981 (preliminary). FIGURE 2. LOCATION OF RAIN GAGES
11
MEAN
MONT
HLY
EVAP
ORAT
ION
AND
RAINFA
LL,
IN IN
CHES
OJ
QJ
-a n> a
n> -s ro O.
CD
C
OJ 3 n> < OJ
a
o -s OJ
c-t-
O cr> i CX3
O
I OQ
"MEAN
MONT
HLY^
AIR
TEMPERATURE,
IN °c
GEOLOGY
This chapter is a summary from "Military Geology of Yap Islands, Caroline
Islands" (Johnson and others, I960).
Descriptive Geology
The geologic map of the Yap Islands (fig. 4) shows the major rock units that
are found on the islands.
The basement rocks were named the Yap Formation by Tayama (1935) who defined
it as "*** the crystalline schists which develop on Yap proper." This formation
underlies the northern three-fourths of Yap Island, the northwestern three-
fourths of Rumung, and a prominent ridge in western Gagil-Tamil. A small outcrop
occupies the hilltop at Leebinaew, on eastern Gagil-Tamil, at the site of a
destroyed lighthouse.
The Yap Formation is a complex of metamorphic rocks of the green schist and
amphibolite facies, that have a considerable range in texture but only a rather
limited range in mineral composition. The formation is pre-Miocene, possibly
Mesozoic, in age. The thickness of the formation is unknown. It is the basement
rock (the lowermost, oldest rock) on the island and its lower limits, therefore,
are not exposed.
The rocks of the Yap Formation weather to fat clay, which is gray to
greenish in color near the weathered rock surface, and grades upward to yellowish
and, in some places, red clay at the surface of the ground.
Serpentinite dikes and sills, mostly 1 to 10 feet thick and of unknown
extent, are scattered throughout the Yap Formation; most are serpentinized
peridotite. The rock is dense, dark green to nearly black, with faint grayish-
green spots or mottles. Only the large outcrop areas in Gagil-Tamil are included
on the geologic map; outcrops on Yap Island are too small to be shown. The age of
the serpentine cannot be determined more closely than pre-Miocene (pre-
Tertiary).
The serpentinite weathers to a ferruginous clay. As much .15 27 feet of this
material was measured with an auger. The clay contains iron and a small percen
tage of nickel. During World War II, the Japanese South Seas Development Co.
prospected the deposits and shipped some ore to Korea and Japan for smelting.
13
138°05'
EXPLANATION
Mangrove swamp deposits
Alluvium, sand
Alluvium, clay
Tamil Volcanics*
Maap Formation*
Serpentinite
Formation*
138°10P
QUATERNARY
TERTIARY
Figure 4. Geology of the Yap Islands (Johnson and others, 1960).
Overlying the basement rocks in the northeastern part is the 01igocene Map
(Maap) Formation of Tayama (1935), composed entirely of fragmental rock of both
tectonic and sedimentary origin, and includes breccia, conglomerate and inter-
bedded sandstone and siltstone. The formation is named from good exposures in
the sea cliffs along the east side of Maap. It also crops out on Gagil-Tamil and
Rumung.
The breccia of the Map (Maap) Formation is a massive deposit of angular to
subangular fragments, mostly of metamorphic rocks but including a great variety
of other rock types, embedded in a matrix of finely crushed rock. Fragment sizes
range from less than 1 inch to 9 feet. The matrix is light gray in color and is
composed of sand-size to clay-size particles of ground rock.
Gravel- to silt-size sediments occupy channels cut into the breccia, and are
faulted into it. Particle size of the conglomerate ranges from fine sand to
boulders. The conglomerate grades laterally and vertically into deposits of
sandstone and siltstone. Most of it is well bedded and up to 8 feet thick.
Faulting of the Map (Maap) Formation has greatly complicated the structure
and stratigraphy of the sedimentary rocks. At almost every outcrop of the Map
(Maap) Formation there are faults, most nearly vertical, that cut the breccia or
sedimentary deposits, or both.
The thickness of the Map (Maap) Formation is variable and any figure given
for it is highly speculative. It is thickest on Maap where it may exceed 250
feet. The formation is considered relatively thin in eastern Gagil-Tamil, as
there are many outcrops of serpentine and rock of the Yap Formation in the area.
The Tomi1 (Tamil) Volcanics of Tayama (1935), composed of andesitic tuffs,
volcanic breccias, and lava flows, all almost completely weathered to clay,
unconformably overlie the breccia and basement rocks in the central part and the
southern-most tip of the Yap Islands. The formation was deposited upon strongly
eroded older rocks and probably is at least several hundred feet thick in central
Gagil-Tamil, where it is typically exposed. The Tomi1 (Tamil) Volcanics probably
are 01igocene and Miocene in age (12-28 million years ago). Hilltops of the
underlying Yap and Map (Maap) Formations protrude through the volcanic deposits
in central Gagil-Tamil and on southern and northern Yap Island.
15
The Tomi1 (Tamil) Volcanics are mostly deeply weathered to a kaolin!tic
clay. The clays generally are deeply eroded because they support only sparse
vegetation and central GagM-Tamil is a wasteland of bare slopes and gullies;
some of the gullies are 50 feet deep, entirely in clay. Such erosion is not as
well developed on Maap and southern Yap Island, but bare slopes and washes are
common.
"Most alluvial deposits are restricted to beaches, because most streams on
Yap are narrow with steep gradients and, therefore, have no flood plains of
alluvium. Only near the shore, where the streams flow at or near sea level does
stream alluvium accumulate to any great amount; in such places it is mixed with
sand blown and washed in from the beach. The largest accumulations of alluvium
are on the southern tip of Yap Island, northwestern Yap Island, the eastern side
of Gagil-Tomi1, and on the east and north shores of Map.
"Mangrove swamps discontinuously border the shores of all the islands of
Yap. Sandy black muck is deposited in the swamps. The muck is thick and soft
where the water circulation in the swamp is very sluggish as along the shores of
Tomi1 Harbor; it is thinner, more sandy, and much more firmly packed where water
circulation is rapid, as in swamps along shores exposed to winds and the sea."
Water-Bear ing Characteristics
"The bedrock of Yap is dense and fractures are tight or are filled with
clay; the rock has very low permeability and contains little water. It is
unsuited for development of water supplies by means of wells. The only practical
means of developing supplies are shallow dug wells, wellpoints driven in the
alluvium, or seep development. Most streams are fed by seeps from along the
banks, rather than from springs.
"The best locations for dug wells or wellpoints in the alluvium of coastal
flats are along the inland margins of the wider flats. Wells in such locations
are more likely to contain fresh water, and they have the least tidal
fluctuation. Wells near the shoreline or on narrow flats are likely to produce
brackish water, and the water levels will fluctuate almost as much as the tidal
range."
16
WATER RESOURCES
General
The systematic collection of water-resources information was begun in March
1968 when five gaging stations were constructed on Yap Island and one on Gagil-
Tami1. Additionally, nine low-flow partial-record stations were established
(fig. 5). At the end of 197^, the gaging station on Gagil-Tamil was moved from
Gilaew Spring to the principal water source on the island, Mukong Stream. In
April 1979, the gaging station at Taalgum Stream, Yap, was discontinued and was
relocated in December 1981 on Qatliw Stream, Yap. Also in December 1981, the
Daloelaeb Stream, Yap, gaging station was moved to Eyeb Stream, Gagil-Tamil.
At gaging stations (figs. 6, 7)» continuous records of gage height are
obtained and from these records daily, monthly and annual discharge totals are
computed. Daily figures of discharge can be found in the Geological Survey
publications or obtained from the Honolulu District office and the Guam Sub-
district office.
Because the number of streams on which streamflow information is likely to
be needed far exceeds the number of stream-gaging stations feasible to operate at
one time, the Geological Survey collects limited streamflow data at sites other
than gaging stations. When limited streamflow data are collected on a systematic
basis over a period of years for use in hydrologic analyses, the site at which
the data are collected is called a partial-record station. Discharge
measurements made at partial-record stations in the Yap Islands are listed in the
Hydrologic Data section, tables 37-^7. Discharge measurements made at sites not
included in the partial-record program are called measurements at miscellaneous
sites (table *i8).
Since 1979, water samples have been collected by the Geological Survey at 23
sites for chemical analyses. No systematic collection of ground-water data has
been made, but in 1979 a number of exploratory wells were drilled and pumping
tests were made (Lyon Associates, 1980). In 1982, 13 production wells were
drilled and pumping tests made (Nance, 1982).
Prior to 1968, virtually no water-resources data were available except for
rainfall data.
17
138"05'E 138°10'E
RUMUNG ISLAND
MAAP ISLAND
GAGIL-TAMIL ISLAND
YAP ISLANDS
CONTOUR INTERVAL (APPROXIMATE) 10 AND 50 METERS DATUM IS MEAN SEA LEVEL
EXPLANATION A CONTINUOUS-RECORD STATION
LOW-FLOW PARTIAL-RECORD STATION A MISCELLANEOUS MEASUREMENT
FIGURE 5. LOCATION OF SURFACE-WATER DATA-COLLECTION SITES.
18
Figure 6. Downstream view of gaging station on Mukong Stream, Gagil-Tamil
Figure 7. Upstream view of gaging station on Qaringeel Stream, Yap,
19
Surface Water
Genera]
Although the Yap Islands have an average yearly rainfall of 122 inches,
there are no perennial streams on the Island of Yap where all streams usually
will be dry during part of the dry season, ranging from a few days to several
months. The largest stream in yearly discharge, Qaringeel Stream, has been dry
an average of 10 weeks a year during 1969-82. The streams go dry because they
have small drainage areas (only a few exceed a quarter of a square mile) and the
water retention of the soil and rock of their watershed is low. The principle
geologic formation of the drainage areas of all Yap streams is the green schist
of the Yap Formation of Tayama (1935).
On Gagil-Tamil, the geologic formation is quite different (see fig. *t).
There, Mukong Stream and adjacent streams in the central valley are not known to
go dry. The principal geologic formation is the deeply weathered Tomi1 (Tamil)
Volcanics of Tayama (1935), which allows greater infiltration of rainfall, and
subsequent release to the streams during long periods of dry weather.
Additionally, the drainage area of Mukong Stream is much larger than any stream
on Yap Island. The different character of the flow of Mukong Stream compared to
that of the Yap stations is illustrated by the flow-duration curves of figure 8.
Table 3 lists the streams and locations where flow data have been collected.
As an added means of identification, each gaging station and partial-record
station has been assigned a station number. In assigning the numbers, no
distinction is made between partial-record and continuous-record gaging
stations. Gaps are left in the numbers to allow for new stations that may be
established. This numbering system is used nationwide.
20
Tabl
e 3-
Surface-water
stat
ions
in
the
Yap
Islands
Station
numb
er
Station
name
Drain,
area
(mi2
)
Lati
tude
nort
h
Loca 1
1 on
Long
itud
e Altitude
east
(ft)
Peri
od of re
cord
(water years)
Remarks
16892000
Qatliw (Atelu)
Stream,
Yap
0.31
9°32'58'
16892400
Qaringeel
(Ari
ngel
) Stream,
Yap
.24
16892450
Faraq
(Fara) Sw
amp
outlets, Ya
p .29
16892460
Galn
gun
Swamp
outlet,
Yap
.16
16892500
Tamaney
Stream,
Yap
.1?
16892600
Ripu
Stream,
Yap
.29
16892650
Dina
ey (Dinay)
Stream,
Yap
.0^4
16892680
Thol
omar
Stream,
Yap
.10
16892700
Thol
omar
(T
halo
mar)
Stream,
Yap
.13
16892800
Daloelaeb
(Dal
olab
) Stream,
Yap
.0?
16892900
Peem
goy
(Pemgoy) Stream,
Yap
. 1*»
16893000
Taal
gum
(Talagu) Stream,
Yap
.08
16893050
Mabu
uq (Mabu) Stream,
Yap
.30
16893100
Buro
ng Stream,
Yap
.23
16893180
Mong
uch
Stream,
Gagil-Tamil
.18
16893190
Dorf
ay Stream,
Gagi
l-Ta
mil
.20
16893200
Muko
ng Stream,
Gagil-Tamil
.50
16893300
Gilaew (Bileiy) Spring,
Gagi
l-Ta
mil
--
9 31
'03"
9°29
'08"
9°29
'15"
9°
29'O
V'
9°29
IJ*9"
9°30
'10"
9°30
'33"
9°
30'3
7"
9°30
'3V
'
9°31
'05"
9°
31'0
8"
9°31
'09"
9°31
'16"
9°32
'05"
9°31
'59"
9°32
'08"
9°
32'0
5"
138°0
5'3
1"
138°O
V2V
138°O
V21"
138°O
V40"
13
8°0
5'5
3"
138°0
6'2
5"
138°0
6'1
V'
13
8°0
6'1
8"
138°0
6'2
1"
13
8°0
6'2
2"
138°0
6'3
6"
138°0
6'3
V'
138°0
7'0
0"
138°0
7'1
9"
138°0
9'5
7"
13
8°1
0'1
3"
13
8°1
0'l8
"
9°32
'16'
bo
1980-81
Feb
ruar
y to
September
1982
15
Apri
l 19
68 to Sept.
1982
5 1968-73
30
do.
30
1968-82
10
do.
75
1980-82
75
1980
-82
70
1968
-7^
110
Apri
l 1968 to
Dec. 19
81
55
Apri
l 19
68 to
July 19
82
75
Apri
l 19
68 to A
pril
1979
k$
1968-72
15
Apri
l 1968 to
Sept.
1982
20
1980-82
10 19
81-8
25
Dec. 197^ to J
une
1978,
Oct.
1978
to
Sept.
1982
60
Apri
l 19
68 to
Sept.
197^
1975-79
Low-
flow
partial
record.
Cont
inuo
us record.
Do.
Low-flow partial
record.
Do.
Do.
Do.
Do.
Do.
Do.
Cont
inuo
us record.
Do.
Do.
Low-
flow
partial
record.
Cont
inuo
us record.
Low-flow partial
record.
Misc
ella
neou
s measurements.
Cont
inuo
us record.
Cont
inuo
us record.
Low-
flow
partial
record.
16893310
1689
3350
1689
3400
16893500
Gila
ew (Bileiy) Stream,
Gagil-Tamil
Yanb
ilan
g Stream,
Gagil-Tamil
Eyeb Stream,
Gagi
l-Ta
mil
Qami
n (Amin) Stream,
Maap
Dali
baec
h Stream,
Yap
.15
.03
.22
.19
.25
9 9 9 9 9°32
°32
°33
°35
°30
12"
45"
11"
'57"
32"
138
138
138
138
138°1
1
°11
°09
°10
°06
29"
48"
'14"
15"
22"
15 5 15 45 65
1968
-78
1968
-72
1980-81
Janu
ary
to September
1982
1980-81
1965
Do.
Do.
Do.
Continuous record.
Low-flow pa
rtia
l-re
cord
.
Misc
ella
neou
s me
asur
emen
t.
Note
: Th
e spelling of names, dr
aina
ge areas, an
d locations
for
most
st
atio
ns differ fr
om th
ose
used in "W
ater
Resources
Data fo
r Hawaii an
d
othe
r Pa
cifi
c Areas",
1968
to
19
80.
Thes
e had
been based
on 195^ Ar
my Ma
p Se
rvic
e 1:
25,0
00-s
cale
ma
p and
10-m
eter
co
ntou
rs (International
Sphe
roid
) wh
erea
s th
e re
vise
d figures
are
based
on th
e 1981 US
GS maps w
ith
1:10
,000
scale
and
5-meter
contours (C
lark
e Sp
hero
id of 1866).
Data collected at continuous-record stations consist of records of stage
and measurements of discharge of the streams. Records of stage are obtained from
a water-stage recorder that provides a continuous graph of the fluctuations of
the water level at the station site. Measurements of discharge are made with a
current meter.
For continuous-record stations, rating tables giving the discharge for a
range of stage (gage height) are prepared from stage-discharge relation curves
defined by the discharge measurements at the stations. Application of the daily
mean stage to the rating table gives the daily mean discharge from which the
monthly and the yearly mean discharges are computed. These records are published
in the annual reports, "Water Resources Data for Hawaii and other Pacific Areas",
for the water year, which begins on October 1 and ends on September 30.
Tables with monthly and annual totals, annual maximums, minimums, and means
are presented in the Hydrologic Data section. Peak discharges and their times of
occurrence and corresponding gage heights are listed for all peaks above a
selected base discharge are given. The base discharge is selected so that an
average of about three peaks a year can be presented. Time is expressed in 24-
hour local standard time.
At the partial-record sites only low-flow data are collected. Most measure
ments are made during periods of base flow, when streamflow is primarily from
ground-water storage. These measurements, when correlated with the simultaneous
discharge of a nearby stream where continuous records are available, will provide
an estimate of the low-flow potential of the partial-record site.
A comparison of the monthly yields from gaged streams on Yap and Gagil-Tamil
is provided in table 4. The table also lists the percentage of days without flow
for each month. The annual percentage of "0" flow days varies for the Yap
stations from 14 percent at Peemgoy Stream to 38 percent at Daloelaeb Stream and
averages 26 percent, which is more than 3 months of the year.
22
Table
4.
Mean
monthly discharge
In cubic
feet pe
r second,
mont
hly
perc
enta
ge of
an
nual
me
ans,
an
d percent
of no
-flo
w days
ro
Year
sof
Name
re
cord
Qar In
geel
(Arlngel)
Stream,
13-14
Yap
Daloel
aeb
(Dalolab)
Stream,
13-1
4Ya
p
Peem
goy
(Pem
goy)
Stream,
13-14
Yap
Taalgum
(Tal
agu)
Stream,
11-1
2Ya
p
Burong
Stream,
Yap
13-14
Mukong
Stream,
Gagl
l-
6- 7
Tamil
G 1 1
aew
(Bil
ely)
Spring,
6- 7
Gagl
l-Tamll
Dal ly me
anPe
rcen
t of
total
Perc
ent
of"0
" days
Dal ly
mea
nPe
rcen
t of
tota
lPe
rcen
t of
"0"
days
Dal ly me
anPercent
oftotal
Percent
of"0
" days
Dal ly me
anPe
rcen
t of
tota
lPercent
of"0
" days
Dal ly
mean
Perc
ent
ofto
tal
Perc
ent
of"0
" da
ys
Dal ly me
anPercent
oftotal
Percent
of"0
" days
Da 1
1 y mean
Perc
ent
oftotal
Perc
ent
of"0"
days
Oct.
1.57
12.3 3.5 .58
13.1
20.1 .9
3
13.6 0 .4
9
12.6
6.1
1.47
13.6
5.0
2.56
11.5
0
.26
17.8 0
Nov.
0.85
6.6
8.5 .38
8.5
20.8 .4
9
7.2
3.3 .31
7-9
9.7 .74
6.8
7.9
1.32
5-9
0 .13
8.6
0
Dec.
1.03
8.0
2.0 .36
8.1
27.8 .5
1
7.4
1.5 .27
6.9
8.5 .99
7.3
2.5
2.44
11.0 0 .0
8
5.2
0
Jan.
0.66
5.2
24.3 .2
1
4.7
48.4 .3
7
5.4
9.4 .21
5.3
31.4 5
6
5.2
26.1 1.68
7.5
0 .10
6.5
13-9
Feb.
0.38
3.0
50.1 .1
2
2.7
70.8 .2
1
3.1
21.3 .1
0
2.6
63.2 .3
3
3-0
49.6 9
4
4.2
0 .05
3-5
27.2
Mar.
0.33
2.6
58.1 .1
2
2.7
76.7 .1
6
2.3
35-2 .1
2
3.2
73.3 .2
7
2.5
68.5 .4
8
2.2
0 .08
5.7
33.3
Apr.
0.33
2.6
70.5 .1
0
2.3
80.5 .1
5
2.2
53.3 .1
0
2.7
73.9 .2
4
2.2
74.0 .6
4
2.9
0
.04
2.9
28.6
May
0.56
4.4
30.9 .1
6
3.6
59.4 .2
7
3-9
29.7 .1
5
3.9
53.0 .3
5
3-2
55.3 1.00
4.5
0
.05
3.5
29.0
June
1.12
8.8
7.1 .37
8.3
22.4 .5
9
8.6
7.6 .35
8.9
23.4 .8
8
8.1
24.8 1.99
8.9
0 .09
6.3
28.6
July
2.06
16.1 1.4 .68
15.3 9.0
1.08
15.7 3.2 .62
15-9
10.2 1.76
16.2 5.8
3.20
14.4 0 .1
5
10.2
19-3
Aug.
1.91
14.9 0.2 .70
15.8 6.0
1.02
14.9 1.2 .57
14.6 7.6
1.60
14.8 1.8
3.08
13.8 0 .1
9
12.8
14.3
Sept.
1.98
15.5 0 .6
6
14.9
12.9 1.08
15.7 0 .6
0
15.5 4.5
1.86
17.1 1.0
2.95
13.2 0 .2
5
17.0 6.6
Annual
1.10
100 21.4 .3
7
100 37.9 .5
9
100 13.8 .3
3
100 30.4 .9
3
100 26.9 1.88
100 0 .1
3
100 17.0
Streamflow characteristics
Rainfal1-runoff relations.--Annual rainfall totals from the National
Weather Service station at the Yap Airport (table 19) are used for all rainfall-
runoff calculations.
The data in table 5 indicate that on Yap Island about half the annual
rainfall runs off as streamflow. As most streams on Yap are dry during much of
January to May, table 6 was compiled to determine the rainfal1-runoff ratio only
during the wet months, June to December, for comparison with the yearly ratio.
The table shows that during the wet season, the mean percentage of direct runoff
of Yap stations is only 7 percent higher than the yearly runoff percentage.
Because the average yearly rainfall for the 13-year period (1969-81) used
for the rainfall-runoff ratio is 120.11 inches, and the long-term (19^9-81)
average is 121.30 inches, the rainfall totals for the 13-year period can be
considered representative of average conditions.
For better comparison between the Yap stations and Mukong Stream, the
average percentage of runoff was also computed for only those years when complete
records were available for both (tables 5 and 6). This showed that the annual
percentage of runoff was practically the same. For the wet months, June to
December, the average runoff of the Yap stations was 9 percent higher than for
Mukong Stream, indicating that on Gagil-Tamil more rainfall became infiltration
than on Yap.
A confirmation of the uniformity of the rainfall in the Yap Islands and the
rainfall-runoff relationship of the streams on Yap is the similarity of the
regression correlations of the annual runoff at Qaringeel Stream with the1 64 rainfall at Yap Airport, Y = 0.024 X " , and of the annual runoff of Burong
Stream with the Yap Airport rainfall, Y = 0.026 X , where Y is the runoff and
X is the rai nfal1.
Tabl
e 5«
An
nual
ra
infa
ll-r
unof
f co
mpar
ison
, 1969-8!
ro
\j-\
(All
data o
n ca
lend
ar-y
ear
basis
and
in in
ches
)
Qar in
geei
Stre
am
Year
1969
1970
1971
1972
1973
1974
1975
1976
1977
1978
1979
1980
1981
Mean
Mean 1975
-77
Annu
a 1
rain
fal
1
Yap
Airp
ort
119.
8011
2.35
148.30
113.
1694.03
147.
7111
6.21
114.
5010
4.10
119-
1812
4.49
120.35
127.
2412
0.11
111.
60
drai
nage
area
0.24
Mean
61.6
557
.12
82.5
855
.43
38.4
688
.80
64.4
852.60
52.60
63.34
60.52
62.2
172.39
ml2 Per
cent
51 51 56 49 41 60 55 46 51 53 49 52 57 52 51
Dalo
elae
b St
ream
drai
nage
area
0.07
Mean
69.8
169
.81
96.96
62.05
50.4
296.96
75-63
63-99
54.30
79-5
167
.87
67.8
781
.44
ml2 Per
cent
58 62 65 55 54 66 65 56 52 67 55 56 64 60 58
Peemgoy
Stre
amdrainage area
0.14
Mean
52.36
49.45
65.93
43.6
342.66
87.26
60.11
59.1
449.45
67.87
58.1
753
.33
67-87
mi2 Per
cent
44 44 44 38 45 59 52 52 48 57 47 44 53 48 51
Taal
gum
Stre
amdrainage area
0.
Mean
62.78
57.6
983
.14
44.1
235
-63
79.7
562.78
52.6
044
.12
61.08
08 m
l2
Per
cent
52 51 56 39 38 54 54 46 42 51 -- 48 47
Burong
Stream
drai
nage
ar
ea
0.23
Mean
48.9
853
.70
73-7
748
.98
37.7
781
.44
54.30
47.21
43.0
856
.66
57.23
54.30
66.10
mi2 Per
cent
41 48 50 43 40 55 47 41 41 48 46 45 52 46 43
Mean
of 5
Yap
sta
tions
49 51 54 45 44 59 55 48 47 55 .. 51 50
-'Mukong
Stream
drai
nage
ar
ea
0.50
Mean __ -- --
54.02
57.28
52.94
39.64
45.34
54.57
ml2 Per
cent
__ 1 47-
50 51 (1)
(D
(D
49 49
The
perc
enta
ge of
rainfall
In a
drai
nage
basin
which
runs of
f Is
determined by converting the
mean discharge
of th
e
ft3/
s x
13.574
area
fr
om c
ubic fe
et pe
r se
cond
to
Inches
3 a
nd comparing
to th
e rainfall
In
Inches du
ring
the
same period.
ml'
(1)
Sinc
e 19
78,
smal
l am
ount
of water
is pu
mped
at times
from
site about
500
feet up
stre
am.
Tabl
e 6.
Rainfal1-runoff
comp
aris
on for
June
to
December,
1969-81
(All
data on ca
lend
ar-y
ear
basis
and
in inches)
Qar in
geel
Stre
am
Year
1969
1970
1971
1972
1973
197*
1975
1976
1977
1978
1979
1980
1981
Mean
Mean 1975-77
June-Dec.
rain
fal
1
Yap
Airp
ort
101.66
84.07
89.20
68.20
77.75
101.77
72.5
975.9
084.79
97.4
297.5
988
.72
97.3
087
.46
77.76
drai
nage
area
0.24
mi
2
Mean
59.69
53.0
652.72
35.81
38.47
68.64
42.4
441.12
49.41
59.36
58.55
51.40
64.34
Per
cent
59 63 59 52 49 67 58 54 58 61 60 58 66 59 57
Daloelaeb
Stream
drainage
area
0.07 mi
2
Mean
68.22
64.8
061
.39
39.7
950
.02
75.04
52.3
052.30
52.3
076.17
65.9
457.98
68.9
1
Per
cent
67 77 69 58 64 74 72 69 61 78 66 65 71 68 67
Peem
goy
Stream
drainage
area
0.14 mi
2
Mean
51.16
42.63
44.34
27.85
42.0
765.94
42.6
346.61
47.18
63.10
55.71
44.91
56.7
9
Per
cent
50 51 50 41 54 65 59 61 56 65 57 51 58 55 59
Taal
gum
Stream
drainage
area
0.08 mi
2
Mean
60.68
51.7
351
.73
27.8
535.81
61.6
849
.74
42.7
842
.78
57.7
0
Per
cent
60 62 58 41 46 61 69 56 50 59 56 58
Buro
ngStream
drai
nage
area
0.23 mi
2
Mean
47.75
47.75
52.60
33.3
937
.72
60.55
39.10
37.68
42.5
652
.59
56.40
44.64
55.93
Per
cent
47 57 59 49 49 60 54 50 50 54 58 50 58 53 51
Mean
of 5
Yap
sta
tions
57 62 59 48 52 65 62 58 55 63 58 58
Mukong
Stre
am
,drainage
area
0.50
mi
2
Mean « M
36.7
441
.96
46.5
6
35.2
135.65
Per
cent
__ 51 55 55 (1)
(1)
53
(1)
Since
1978
, sm
all
amou
nt of water
is pumped at
times
from
si
te about
500
feet
up
stre
am.
Flow-duration curves. A flow-duration curve is a cumulative frequency
curve showing the percentage of time within the total period of record that a
specified daily discharge was equaled or exceeded. It combines in one curve the
flow characteristics of a stream throughout the range of discharge without regard
to the sequence of occurrence. The general shape of such a curve is influenced
by many factors, such as basin slope and cover, ground-water contributions,
precipitation, and diversions or inflows.
The curve is plotted from a flow-duration table, which shows the distri
bution of daily discharge by different class limits in increasing order of
magnitude. Discharge in cubic feet per second is plotted on the ordinate and
percent-of-time equaled or exceeded is plotted on the abscissa. The flow-
duration tables in this report are based on distribution of the daily discharge.
For comparison of the curves for different streams, data covering the same
period should be used to avoid including an extremely dry or wet year in one set
and not in the other.
Flow-duration curves are used to determine the percent of time that a
certain amount of water was available during the period of record. This informa
tion is essential for planning of stream diversions for water supply or to assess
hydroelectric potential.
The flow-duration curves for four streams on Yap and one on Gagil-Tamil are
given in figure 8. The streams, their drainage area, and the period of record
are:
Area Years2 (mi ) of record
Qaringeel Stream, Yap 0.24 11
Daloelaeb Stream, Yap --- - --- .07 11
Peemgoy Stream, Yap ---- ------- .14 ]]
Burong Stream, Yap - --------- .23 11
Mukong Stream, Gagil-Tamil ----- .50 3
The duration curve for Taalgum Stream, Yap, for which 10 years of data
are available, is not plotted because the curve is almost identical to the
one of Daloelaeb Stream.
27
100 rr
o o
UJ Q.
UJ UJ U.
OI 4
CQ
O z.\ 4
t
UJ
in oi iQ
1.0
EXPLANATIONYap Island
Qaringeel Stream, 1969-79 Daloelaeb Stream, 1969-79 Peemgoy Stream, 1969-79 Burong Stream, 1969-79
Gagil-Tamil Mukong Stream, 1976-77, 1979
\\ \\.
0.1
0.01
PERCENTAGE OF TIME INDICATED DISCHARGE WAS EQUALLED OR EXCEEDED
Figure 8. Flow-duration curves of four streams on Yap Islandand one on Gagil-Tamil.
28
The similarity of the duration curves of all five Yap stations shows the
comparability of their drainage areas; the only exception being Peemgoy Stream
with some retention of rainfall in the watershed. This retention is also
indicated by Peemgoy Stream having the fewest number of days without flow.
Only 3 years of complete record without diversion of some of the flow are
available for Mukong Stream on Gagil-Tamil, but the mean rainfall during these 3
years differs by only 1 percent from the mean rainfall during the 11-year period
used for the Yap streams. The contrast between the curves indicates a difference
in the geology of the drainage areas as described previously.
Low-flow frequency tables.--Low-flow tables show the lowest mean discharge
for certain periods of consecutive days. Because all Yap streams have no flow
during part of the dry season, low-flow frequency curves would not be very
meaningful and only the tables are provided (table 7).
For Mukong Stream, Gagil-Tamil, only a few years of complete record are
available and this station is not included in the table.
High-flow frequency curves.--High-flow frequency curves show the maximum
mean discharge for certain periods of consecutive days and its likelihood of
occurrence. These curves can also be used to show the frequency of instantaneous
annual peak discharge.
Figures 9-13 show the recurrence intervals of the maximum mean discharge for
six periods of consecutive days for the five continuous-record stations on Yap
Island. The period of record for the continuous-record stations on Gagil-Tamil
was of insufficient length to be used for frequency curves. The uniformity of
the curves for the Yap stations show the similarity of their basins.
Figure 14 shows the magnitude and frequency of annual and instantaneous peak
flows for four continuous-record stations on Yap with 11 years of complete
record.
High-flow frequency curves provide information needed to determine the size
of reservoirs and diversion structures.
Frequency curves for annual peak flows are needed to size and design storm
drainage systems, culverts and bridge openings.
29
Table 7- Lowest mean value for a number of consecutive days for yearsending September 30
Year
196919701971197219731974197519761977197819791980
196919701971197219731974197519761977197819791980
196919701971197219731974197519761977197819791980
1
00.01
000000000
000000000000
00.01
000000000
(Di
7
00.03
000000000
000000000000
00.02
0000000.01
0
ischarge in cubic feet per second)
14
Qar ingeel
00.13
000000000
Daloelaeb
00.02
000000000
Peemgoy
00.05
0000.01
0.01.01
0
Days
30
Stream, Yap
00.50.03
0.07
000000
Stream, Yap
00.17.01
00000000
Stream, Yap
00.18.01
0.02
0.01
0.01.01.01
60
0.05.81.06
0.21
0.06
000.06
0.01.23.02
0.05
0.02
0000
0.02.32.03
0.11.01.04
0.01.01.02
90
0.12.80.26
0.34.01.08
00.06.23
0.03.23.07
0.09
0.03
00.02.08
0.08.31.10
0.20.03.05
0.01.04.11
120
0.01.19.92.48
0.56.34.24.01
0.05.29
0.05.27.16
0.17.08.08.01
0.02.08
0.01.11.37.21
0.34.14.12.02.03.04.11
30
Table 7. Lowest mean value for a number of consecutive days for yearsending September 30--Cont inued
Year
1969197019711972197319741975197619771978
19691970197119721973197^197519761977197819791980
1
00.01
0000000
00.01
000000000
(Di
7
00.01
0000000
00.03
000000000
scharge i
14
Taalgum
00.03
0000000
Burong
00.06
000000000
n cubic feet
Days
30
Stream, Yap
00.12.01
000000
Stream, Yap
00.39.02
0.02
000000
per second)
60
00.26.02
0.05
0.02
00
0.01.59.05
0.20
0.04
000.02
90
0.03.25.06
0.10.01.03
00
0.07.64.13
0.38.01.05
00.03.21
120
0.01.04.28.13
0.18.07.07.01
0
0.11.71.36
0.54.15.13
0.01.03.26
31
TOO 1 I I I I I I
Drainage area, 0.24 square mile Period 1969-81
1.1 1.5 2 5 RECURRENCE INTERVAL, IN YEARS
10 15 20 25
Figure 9. Magnitude and frequency of highest mean discharge for durationindicated. Qaringeel Stream, Yap.
32
Drainage area, 0.07 square mile Period 1969-81
0.11.01 1.1 1.5 2 5
RECURRENCE INTERVAL, IN YEARS15 20 25
Figure 10. Magnitude and frequency of highest mean discharge for durationindicated. Daloelaeb Stream, Yap.
33
50
10
I I I I I i i i i r I I
Drainage area, 0.14 square mile Period 1969-81 \ day
LU CO
CtL LiJ 0.
CO ID O
CD
COi i Q
0.1 I I I I I1.01 1.1 1.5 2 5
RECURRENCE INTERVAL, IN YEARS10 15 20 25
Figure 11. Magnitude and frequency of highest mean discharge for durationindicated. Peemgoy Stream, Yap.
50 I I I l I I I I I
10
oC_3 LU CO
o:LU D-
h-LU
C_3 i i CO ID C_3
O
C_3 CO
O
0.11.01
Drainage area, 0.08 square mile Period 1969-78
1.1 1.5 2 5 RECURRENCE INTERVAL, IN YEARS
15 20 25
Figure 12. Magnitude and frequency of highest mean discharge for durationindicated. Taalgum Stream, Yap.
100
oO
CO
UJ Q_
O i i COID O
C3 C£<C
O CO
Q
I III I I I I I I I I
Drainage area, 0.23 square mile Period 1969-81
30 day
60 day
1.1 1.5 2 5 RECURRENCE INTERVAL, IN YEARS
10 15 20 25
Figure 13. Magnitude and frequency of highest mean discharge for durationindicated. Burong Stream, Yap.
36
1000
o oUJGO
UJ Q_
o 100 i iCOZD O
o oo
1 IT
101.1
Qaringeel Stream Burong Stream
Peemgoy Stream
Daloelaeb Stream
1.5 2 5 10 15 RECURRENCE INTERVAL, IN YEARS
Figure 14. Magnitude and frequency of annual and instan taneous peak flows for four continuous-record
stations on Yap Island, 1969-79.
37
Correlation of partial record with continuous record
A low-flow partial-record station is operated to determine the low-flow
characteristics of a stream through correlation with concurrent discharges at
continuous-record gaging stations.
The discharge measurements of five partial-record stations were correlated
with discharge records for nearby gaging stations (table 8). Because Mabuuq
Stream, is nearly equidistant from Peemgoy and Burong Streams, a correlation with
both streams was made, and this yielded almost identical results. The
correlation with Burong Stream was selected because of the better correlation
coefficient and lower standard error.
Discharge measurements for all partial-record stations could not be
correlated with discharges at continuous-record stations because flow character
istics of Faraq and Galngun Swamp outlets differ from those of the continuous-
record stations and discharge of Yanbilang Stream, Gagil-Tamil proved to be too
small for correlation.
Figures 15-19 show the regression lines of the five partial-record
stations. From these lines, a reasonable estimate of low flows can be made using
the known discharge of the nearest continuous-record station.
Historical and existing developments
Because of the prolonged dry season, normally from January to May, the
limited quantity of rain stored as ground water, and the small drainage areas,
all streams on Yap Island are dry part of the year. As a consequence, there is a
need for surface-water storage. The first storage dam was built on Tamaney
Stream during the German Administration. This earthen dam, about 8 feet high and
100 feet long at an altitude of about 25 feet, was built to store water primarily
for a communication station and a nearby German settlement. The center of the
dam was subsequently washed out by floodflows. Local residents say that the
reservoir wasn't used during the Japanese Administration.
Gitaem was the site of the first central water supply system in Yap. An
earthen dam was built across Dalibaech Stream in 1951 with a storage capacity of
2 Mgal (million gallons). Water from the reservoir was distributed by 3~and 4-
inch galvanized pipes. Later (1965)? a treatment plant was installed with a 200-
gal/min (gallons per minute) capacity.
38
Table 8. Correlation between discharges at low-flow partial-recordand cont i nuous-record stations
[Y, discharge at part ial -record station; X, discharge at continuous-record station]
Partial- record station
Tamaney Stream, Yap
Ripu Stream, Yap
Tholomar Stream, Yap
Mabuuq Stream, Yap
G i 1 aewStream, Gagi 1- Tami 1
Dra in-age Contin- area uous
(square record mi les) station
Qar i ngeel Stream,
0.17 Yap
Qar i ngeel Stream,
.29 Yap
Qar i ngeel Stream,
.13 Yap
Peemgoy Stream,
.24 Yap
Burong Stream, Yap
G i 1 aewSpring, Gagi 1-
.15 Tamil
Dra i n-age area
(square mi les)
0.24
.24
.24
.14
.23
Corre- 1 at ion coeff i- ci ent
0.93
.95
.96
.93
.96
.88
Standard error
i n percent
0.12
.10
.12
.21
.14
.17
Regress! on equation
Y = 0.702 X °' 897
Y = .844 X °- 913
Y = 1.009 X °' 899
Y = 1.792 X °' 895
Y= .865 X 0 ' 870
Y = 1.819 X °' 872
39
0.05 0.1 0.5 1 5 DISCHARGE AT CONTINUOUS-RECORD STATION QARINGEEL STREAM, YAP (16892400),
IN CUBIC FEET PER SECOND
10
Figure 15. Correlation between discharges at lamaney and Qaringeel Streams.
0.05 0.1 0.5 1 5 DISCHARGE AT CONTINUOUS-RECORD STATION QARINGEEL STREAM, YAP (16892400),
IN CUBIC FEET PER SECOND
10
Figure 16. Correlation between discharges at Ripu and Qaringeel Streams.
0.05 0.1 0.5 1 5 DISCHARGE AT CONTINUOUS-RECORD STATION QARINGEEL STREAM, YAP (16892400),
IN CUBIC FEET PER SECOND
10
Figure 17. Correlation between discharges at Tholomar and Qaringeel Streams.
10
o-iCQ o
1 I I I i i I
Y=1.792X0.895
0.1
O
O
o o
0.010.01
O
0.05 0.1 0.5 1 5 DISCHARGE AT CONTINUOUS-RECORD STATION PEEMGOY STREAM, YAP (16892900),
IN CUBIC FEET PER SECOND
10
Figure 18. Correlation between discharges at Maabuuq and Peemgoy Streams.
o oCO COen00vo
<cI
GO Qz
is oLiJ <_> <I LlJ _J CO
LLJ Q-
CO
Q i i rv roO =3
LU
I i i_J<c
0.1
Q_
LLJ C£3a:
ooI I Q
Q LiJ C£IDco
0.010.01 0.05 0.1 0.5 1
DISCHARGE AT CONTINUOUS-RECORD STATION GILAEW SPRING, GAGIL-TAMIL (16893300), IN CUBIC FEET PER SECOND
Figure 19. Correlation between discharges at Gilaew Streamand Gilaew Spring.
Miller and Arnow (written communication, 1965) estimated that 20,000-25,000
gal/d (gallons per day) were pumped from the Gitaem Reservoir to a 42,000-galIon
tank for use at the high school plus faculty homes and to three 12,000-gal Ion
concrete tanks in Colonia built by the Japanese. Also 40,000 to 50,000 gal/d
were distributed by gravity to Colonia. In 1959, a 450,000-galIon emergency
storage reservoir was constructed at the Colonia dock area. This emergency
reservoir also received rain runoff from the roof of the supply building. Water
from this reservoir was used to supply ships and, via two booster pumps near the
Spanish well, to the three 12,000-galIon tanks. Leakage of the old 4-inch
distribution pipes was estimated by Austin, Smith and Associates, Inc. (1967) to
be 40-45 percent of the total water production.
The supply of drinking water for Colonia often would be insufficient during
the dry season. It then was necessary to haul water from a pond at the airfield
and to severely limit consumption. This pond, which is called Airport Swamp or
Luweech Swamp, averages about 500 feet in diameter and is estimated to be 10-15
feet deep. It has never been known to go dry (fig. 20).
A new dam at Gitaem was completed in 1975 and increased the water-storage
capacity by 25 Mgal (figs. 21 and 22).
Water production of the treatment plant at the lower dam is metered and a
log is kept at the site (fig. 23). No production figures were available for
periods when the meters were not working. For 1978, however, meter readings were
almost complete and showed a mean monthly clear-water production of 9 Mgal with a
maximum monthly output of 11 Mgal during September of that year.
In 1975, part of the old distribution system was replaced by 6-inch to 10-
inch asbestos distribution pipes. Two 1-Mgal storage tanks were then built at
Nimaar and in Dalipeebinaew (fig. 2k).
By 1980, almost all of the remaining 4-inch pipes were replaced, but the
problem of leakage remained. This leakage is caused by poor connections between
the old and new pipes, breaks in the new pipes where insufficient cushion
material was used, and open or dripping water fixtures.
to c
-s CD ro
o -s TD
O
-a
</>C
U
QJ
3
3CD
TD
CD OJ
CD
O
O-J
- 7T
3 CQ
O
-h
3
O
C-,
-s
cor+
~a
3-
CU
' 3
fl)
(/
i CD tQ
Figure 21. 25-Mgal (upper) reservoir at Gitaem, Yap (view facing north).
Figure 22. 2-Mgal (lower) reservoir at Gitaem, Yap (view facing north).
Figure 23. Treatment plant at Gitaem, Yap (view facing west).
l million
gallon steel
dist
ribu
tion
tank
(30'
high t
ank
has
244'
ov
er
flow s
pill
way
elevation)
10 m
illion g
allon
stee
l di
stri
buti
on t
ank
(30'
high t
ank
has
198' over
flow s
pill
way
elevation)
Gate
valve a
t th
is
loca
tion
is o
per
at
ed to
limit w
ater
service
hours
DA
CH
AN
GA
R
VIL
LA
GE
GITAEM
RESERVOIR
(25
million
gall
ons)
Location o
f the
New
Dock
GIT
AE
M
VIL
LA
GE
WO
RW
OQ
'
VIL
LA
GE
Raw
Wat
er
Pum
ps
Tre
atm
ent
Pla
nt
Boost
er
Pum
ps
DO
NIT
SC
H
(Site
of
the
Sew
age
Tre
atm
ent
Pla
nt)
NG
OL
OG
V
ILL
AG
E
Senior H
igh
School
EXPL
ANAT
ION
1950 T
O 19
60
1970
TO
1980
DIAMETER O
F PIPELINE,
IN I
NCHES
LENGTH O
FP
IPE
LIN
E,
IN
FEE
T
Modifi
ed
from
Ly
on
Ass
oci
ate
s,
1980
FIGURE 2
4,
COLONIA
CENTRAL
WATER
SYSTEM,
Lyon Associates (1980) calculated leakage to be 240 gal/min. This
necessitated closing the distribution system except for a few hours per day as
the amount of leakage during a 24-hour period would be 345,000 gallons, exceeding
the capacity of the treatment plant.
Young and others (1977) took six grab samples from the distribution system
(date and location of samples unspecified, table 9) which showed that although
the total coliform count in the upper Gitaem Reservoir was 5,800 per 100 ml
(mi 11 i 1 i ters) and 95 per 100 ml in the lower reservoir, the levels in the
distribution system were very low.
On April 8, 1979, the tap water in Colonia had a pH of 9.1 and a specific
conductance of 170 ymhos (micromhos) (USGS). The reason for this high pH reading
is not known. From table 9 it appears the pH varies depending on where the sample
was taken from the distribution system.
A chemical analysis of a water sample taken by the Geological Survey on
September 20, 1980 of the finished water from the Gitaem treatment plant is shown
in table 57 in the Hydrologic Data section. The pH reading for this sample
appears to be normal.
Ground Water
Historical developments
Historically, villages depended upon rain catchments, shallow dug wells,
and springs for water. The only known ground-water development was a well dug by
the Spanish in a coastal flat of Colonia. After the construction of the dam on
Dalibaech Stream in 1951, the well was used only occasionally until abandoned
because of a slow recovery rate. During the Japanese Administration, concrete
ci sterns were bui 11 and wel 1 s dug in some vi 1 lages, but most of these have fal len
into disrepair.
In the early days of the American Administration (1947), a 10-foot deep, 10-
foot diameter well was dug about 300 feet west of the Spanish well in Colonia
(see figure 28). At the time, the Spanish and the American wells were connected
by a pipeline, and water was pumped from the American well to the Spanish well
and from there to service tanks. It is not known whether the American well was
used for any length of time.
Table 9- Results of chemical and microbiological analyses on six grab sampler from the Colonia water-distribution system
[Total dissolved solids estimated on the basis of 65 percentof conductivity, as indicated in U.S. Geological Survey
Water Supply Paper 1454. All determinations were made in the field(Young and others, 1977)1
Parameter Units Low
Concentration
High Mean
Chloride mg/L
Chlorine residual (total) mg/L
Conductivity ymho
Dissolved solids --- mg/L
Color, color units
Fluor ide mg/L
Hardness as CaCO, - mg/L
pH ......................
Temperature -- --------- c
Total coliform per 100 mL
Nitrate as N --- -- mg/L
Turbidity NTU
9
0.0
95
62
< 5
0.1
68
7.2
29
0
4
16
0.3
180
117
45
0.5
103
8.8
32
1
6
13
0.1
140
91
26
0.2
92
7.8
31
0
4
4
50
Nature and occurrence
In "Military Geology of the Yap Islands," the authors concluded that because
of dense bedrock with clayfilled fractures, the rock would have low permeability
and contain little water. This was concluded on the basis of surface reconnais
sance, as no drilling equipment was available.
Sunn, Low, Tom, and Hara, Inc. (1971) recognized the availability of ground
water in central Tamil and, to a certain extent, in southern Yap on the basis of
tests made on existing shallow wells and hand auger ing. Two wells were located
on Tamil, one about 1,600 feet south of the LORAN station, the other about 2,300
feet north of Tamilang School at altitudes of 50 and 40 feet above mean sea
level, respectively (fig. 25). At both sites the water surface was 3 inches
below ground level but was quickly drawn down when bailed or pumped. The authors
concluded that development of ground water in the central valley of Tamil might
not be feasible as the ground water is perched at the shallow depth on stiff
clayey silt and the aquifers have low permeability with a very limited storage
capaci ty.
An existing spring at an altitude of 40 feet in Daabach on the west coast of
Tamil, with a flow rate of 3-7 gal/min (measuring date not given), could supply
water to the local inhabitants but this was not thought feasible for development
as dwellings are widely scattered (fig. 25). However, Nance (1979) reports that
the spr i ng suppli ed water through a 2-i nch polyethy1ene pi pe to Rumuug vi11 age on
Yap Island.
At Gagil municipality, two shallow borings were drilled on east Gagil near
the coast, but because of contamination of the ground water by decayed organic
matter, no pumping tests were made and the area was considered unsuitable for
water supply.
In Kanifaay, in southern Yap, two shallow wells were found. The first,
about 650 feet west of the existing church and school in a narrow ravine at about
a 15-foot altitude (fig. 25), has a diameter of 4 feet and is partly lined with
steel casing with the water table standing several inches below the collar.
Local residents reported that the well water was used for drinking. Information
on the yield was not available.
51
138°05'E 138°10-E
RUMUNG ISLAND
MAAP ISLAND
GAGIL-TAMIL ISLAND
p : V U.S. Oi,«frCoait Guard
YAP ISLANDS
01234 KILOMETERS
CONTOUR INTERVAL (APPROXIMATE) 10 AND 50 METERS DATUM IS MEAN SEA LEVEL
2 WELL (Number refers to listing in table 10)
FIGURE 25. LOCATION OF WELLS AND SPRING ON GAGIL-TAMIL AND SOUTHERN YAP, 1971.
52
The second well is located southwest of the first, at an altitude of approx
imately 5 feet. It is about 4 feet square and lined with schist boulders. The
water table was standing at about 1.4 feet below ground surface. According to
local residents the well was abandoned because of salinity and poor supply during
the dry season.
Three 6-inch-diameter, 9-foot-deep holes were drilled for pumping and
observation about 250 feet east of the central-road and Malaay village-road
intersection. Water was encountered at a depth of 3.2 feet but dropped 1.6 feet
after 4 hours when pumped at a rate of 6 gal/min, remaining at that level for an
additional 2 hours of pumping.
From their investigation the authors (Sunn, Low, Tom, and Hara, 1971) con
cluded that shallow ground-water sources in southern Yap could be developed
satisfactorily throughout most of Kanifaay municipality, using infiltration
galleries in the wider coastal flats and shallow dug wells above narrow flats.
Measurements of chloride and dissolved solids at seven sites are listed in
table 10.
Table 10. Partial chemical analyses of water samples taken January 1971
Site Number
1
2
3
4
5
6
7
Daabach
Test wel
Test wel
Test wel
Exi st i ng
Exi st i ng
Test wel
[Source: Sunn, Low, Tom and
Location
(Deboch Village) Spring, Tamil
1 near LORAN station, Tamil
1 near Tami 1 School
1 near Tami 1 School
wel 1 in Kan ifaay
wel 1 in Kan ifaay
1 in Malaay (Malai), Kanifaay
Hara, 1971]
Chloride (mg/L)
10.5
10
15
10.5
13.5
7
7
Total di ssol ved sol ids (mg/L)
136
58
20
88
178
276
360
53
In 1977* while testing drilling equipment for subsurface investigations for
a proposed new airport, Lyon Associates Inc. (Nance, 1979) drilled a test hole
behind the Communication Station near the existing airport. The bit penetrated
30 feet of clayey soil followed by 70 feet of sandy silt. The hole was cased with
2-inch galvanized pipe, and since then the well has been producing water for the
Communication Station at a rate of about 300-500 gal/d. (For chemical analyses
of the water by USGS, see table 60.)
In 1979, 15 exploratory wells were drilled by Lyon Associates (fig. 26).
One hole was drilled in serpentine rock next to Gagi1 School. Below 13 feet of
sand and silt, decomposed serpentine was encountered grading into highly
fractured rock 7 feet farther down. No water was found. Four wells were drilled
in Tamil and, below a surface layer of 5-1^ feet of clayey soil, sandy silt was
found to a depth ranging from 33 feet to about 100 feet where basement rock of
schist was encountered. Similar conditions were encountered at three drilling
sites near the Yap Airport. The basement rock was almost impermeable and formed
a bottom to the sand and silt which contained some water. Because of the areal
extent of this layer of sand and silt, this aquifer should be able to yield a
limited amount of water (Nance, 1979)*
In southern Yap, where three wells also were drilled, no permeable material
was encountered, as the clayey silt was found to be resting directly on the
basement rock. This rock, decomposed schist at the top and fractured schist
below, was considered impermeable as the fractures appeared to be filled with
clay (Nance, 1979). This differs from the findings of Sunn, Low, Tom, and Hara
(1971) who concluded that shallow wells in or near the coastal flats could be
developed satisfactorily.
On the west coast of Yap Island four wells were drilled, three in schist and
one in the alluvial material of the Qokaaw River valley. Permeability of the
rock formation was poor and ground-water yield questionable, at best. The Qokaaw
well proved to be located in an old mangrove swamp.
138°05'E 13810'E
RUMUNG ISLAND
MAAP ISLAND
GAGIL-TAMIL ISLAND
YAP ISLANDS
CONTOUR INTERVAL (APPROXIMATE) 10 AND 50 METERS DATUM IS MEAN SEA LEVEL
EXPLANATION® EXPLORATORY WELL. 1979 PRODUCTION WELL, 1982
FIGURE 26, LOCATION OF WELLS DRILLED IN 1970 AND 1982,
55
Lyon Associates (1980) concluded that the large aquifers in central Tamil
and the airport area would be well suited for ground-water development. Although
the permeability of the deeper sandy silt is not high, the central Tamil aquifer
could provide water for most of the people on Gagil-Tamil, and the airport
aquifer could supply all of southern Yap. Water use in the villages is estimated
to be as low as 20-40 gallons per person per day. Drilling logs, pumping tests,
and a listing of the springs, seeps, and dug wells of the Yap Islands can be found
in "Yap Islands, Groundwater Exploration April to August 1979" by Tom Nance for
Lyon Associates, Inc.
Following the recommendations of Nance, 13 wells were drilled in the first
few months of 1982--7 in the central valley of Tamil, 5 near the Yap airport, and
1 at Magaaf Stream, Yap (fig. 26). On Tamil, the depths of the 4 southernmost
wells varied from 71 to 87 feet below mean sea level and the depths of the other 3
wells varied from 93 to 145 feet. The water-bearing formation of the Mukong
Stream well was white coral rock and that of the other 6 wells, medium-hard brown
rock. The combined aquifer yield is expected to exceed 200 gal/min (Nance,
1982). A 24-hour pumping test of three of the southernmost wells caused drawdown
at all wells except the Mukong Stream well. This indicates that the Mukong
Stream well draws from a separate aquifer. Water from the wells will be pumped
to a 100,000-galIon tank for distribution to nearby villages.
Five wells were drilled northwest of the Airport Swamp on Yap Island. All
were drilled until hard schist rock was encountered at a depth of 25 to 50 feet
below mean sea level. The water-bearing rock, just above the hard schist,
consisted of softer greenish-gray and gray rock. A combined yield of 100 gal/min
is expected (Nance, 1982). The water will be used to supply villages in "the
southern part of the island.
Chemical analyses of water from each aquifer, the two on Tamil and the one
near the ai rport, are given in table 61 and show the water to be of good quali ty.
The well drilled at Magaaf Stream was located 4 feet from the test hole
drilled in 1979. At this well, the water comes from schist rock in the middle
depth and the bottom of the well. The yield of the well during the dry season is
expected to be at least 10 gal/min.
Drilling logs of the 13 wells and of four test holes and results of pumping
tests can be found in "Yap Island Water Well Development, January to March 1982,"
by Tom Nance (1982) for Lyon Associates, Inc. Readings of the depth to water of
12 of the wells are given in table 11.
56
Table 11. Depth to water, in feet, of wells on Yap and Gagil-Tamij
[Measuring point is top of casing]
Well
-''Altitude top of casing (ft) Depth to water
Yap Island
Nance. 1982
1982
Yugamanman 1 42.68 15.52Yugamanman 2 38.83 12.83Timlang 1 42.68 9-01 10.43 11.30Timlang 2 40.43 9.10 10.32 11.79Timlang 3 44.22 12.33 13-44 13.02
U.S. Geological Survey
Yap Island
Magaf
Yugamanman 1Yugamanman 2Timlang 1Timlang 2Timlang 3
Gagi 1 -Tami 1
Monguch 1Monguch 2Monguch 3Monguch 4MukongDorfay 4"Dorfay 6"
42.6838.8342.6840.4344.22
21.3826.47
25.8329.9330.92
Aug.3
8.94
July
13-3011.158.198.35~
June26
02.971.745-639.787.8111.49
Sept.1
8.95
12.2410.30
4.546.43
01.751.585.399.647.2311.22
Sept.16
__
01.841.705.57
8.0011.37
1982Sept.30
8.73
13.0510.80
7.438.02
Sept.29
.172.322.356.4310.199.1311.67
Oct.28~
14.5312.068.619.51
.402.662.776.8910.389.5611.86
Nov.18
9.63
16.3813.4011.0512.86
.642.973.137.4110.579.6511.93
Dec.22
15-6012.859.8011.58
.402^582.636.7510.329.6010.60
Jan.27
19.6916.1914.8217.26
1.233.703.978.3811.37
1983Feb.22
23.3819.6020.6021.43
Feb.21
1.864.504.879.4212.07
Mar.30
26.8323.0825.6027.10~
1.695.60
10.7812.39
debris in well12.60 13.29 14.39
Note: Yugamanman wells also called Faraq-Lamaer wells and Timlang wells also called Weather Bureau wells.
From Nance, 1982.
57
Water QualIty
General
Rainfall is the source of all surface water of the Yap Islands. The quality
of the surface water is good as the concentration of all chemicals analyzed are
well within the maximum permissible level recommended for domestic use by the
World Health Organization (1971).
A number of stream-water samples were collected from pools at gaging
stations where the streams were either not flowing or almost dry when visited.
These samples may not be representative of regular streamflow and results are not
included in the following assessment of the surface water.
The dissolved solids concentration of surface water on the Island of Yap
ranged from 48 to 104 mg/L (milligrams per liter) and on Gagil-Tamil from 23-83
mg/L. S i 1 i ca con cent rat ions rangi ng from 9.5 to 23 mg/L and const i tut i ng from 20
to 35 percent of the dissolved sol ids on Yap and concentrations of 4.4 to 18 mg/L
constituting from 16 to 36 percent of the dissolved solids on Gagil-Tamil, are
characteristic of rain water flowing over tropical volcanic terrain. Other
constituents in decreasing order of concentration were chloride, magnesium,
calcium, sodium, sulfate, potassium, nitrite plus nitrate nitrogen, and
f1uor ide.
The iron concentration of surface water on Yap Island ranged from 81-450
yg/L (micrograms per liter) with a mean of 237 yg/L (25 analyses). Iron concen
trations for streams on Gagil-Tamil were as high as 1,000 yg/L and averaged 332
yg/L (15 analyses). Iron is a minor element in water but can cause considerable
problems when the concentration exceeds 300 yg/L. It can cause problems with
taste, discoloration, turbidity, and growth of iron bacteria. The World Health
Organization (1971) recommended a desirable level of 100 yg/L and a maximum
permissible level of 1,000 yg/L.
Runoff from tropical storms is usually flashy and can cause turbidity
problems in stream water and coastal waters. However, storm duration is
generally short and streams revert to base flow with clear water within a short
time. Physical quality data, in terms of specific conductance, pH, temperature
and turbidity, are included in the chemical analyses as an integral part of the
baseline information.
58
Specific conductance is expressed in micromhos per centimeter at 25 C. It
is a measure of the ability of water to transmit an electric current and is used
as an indicator of the concentration of dissolved solids in water; the more
dissolved solids, the greater the conductance. The specific conductance of
stream water on the Yap Islands did not exceed 138 umhos.
A measure of acidity or basicity is pH. In natural water, the level of pH
depends on chemical and biological processes. For streams on Yap Island, pH
values ranged from 7.1 to 7.4 and for Gagi1-Tami1 from 6.1 to 7-3. The levels are
within the recommended range for public water supply (World Health Organization,
1971).
Chemical analyses
Before 1979 there were no systematic chemical analyses made of water from
sources in the Yap Islands. In 1928, Hajime Arai took 144 samples from water
sources in the Japanese administered islands; a number of these samples were from
Yap (Naval Medical Association Bulletin). The analytical results are not listed
here because a copy of this publication could not be obtained.
In response to a request by the High Commissioner of the Trust Territory of
the Pacific Islands, Ted Arnow of the U.S. Geological Survey reported on the
water-supply conditions on Yap (written communication, Nov. 12, 1952). On
September 30, 1952, he collected a water sample from the Spanish well in Col onia
for chemical analyses (fig. 27). The water had a pH of 7.2, a specific
conductance of 513 umhos and the dissolved constituents listed in table 12.
Water samples for bacteriological and chemical analyses were collected at
seven locations in the Yap Islands by Austin, Smith, and Associates (1967) in
August 1967 and the results of the chemical analyses are listed in table 13.
Bacteriological analysis revealed 600 coliform colonies in a 10-mL sample taken
from the Airport Swamp, while untreated water at the Gitaem Reservoir and water
from Chamorro Bay and at several locations along the coast near Colonia had in
excess of 24,000 coliform colonies per 10 ml.
A water sample taken by the U.S. Geological Survey on August 11, 1978 from
the well at the Communication Station showed 20 mg/L chloride and on April 8,
1979, the pH and specific conductance of water from the Airport Swamp were 8.5
and 160 umhos (USGS). In August 1979, water samples were taken for Lyon
Associates (Nance, 1979) from the Faraq test well on Yap and from Monguch Stream
on Gagil-Tamil. The analytical results are listed in table 14.
59
138°05'E 138'10-E
SwampMitsui
.-- Airport Galngun/f. . Swamp ,
mpSf Y Lamaer well
' J~*-^
YAP ISLANDS
01234 KILOMETERS
CONTOUR INTERVAL (APPROXIMATE) 10 AND 50 METERS DATUM IS MEAN SEA LEVEL
EXPLANATION
T USGS SAMPLING SITE (TABLES 49-60)
v SAMPLING SITE AUSTIN, SMITH, 1967 (TABLE 13v SAMPLING SITE NANCE, 1979 (TABLE 14)$ SPANISH WELL IN COLONIA (TABLE 12)v SAMPLING SITE NANCE, 1982 (TABLE 61)
FIGURE 27. LOCATION OF SITES WHERE CHEMICAL ANALYSES OF WATER WERE MADE.
60
Table 12. Chemical analysis of water from the Spanish well (1952)
[Collected: September 30, 1952. Analyzed by
U.S. Geological Survey, Salt Lake City Laboratory]
Di ssol ved
constituent
Silica (SiO )
Iron (Fe) - - - -
Calcium (Ca) - -
Magnesium (Mg) ------------------------
Sodium (Na) -- -
Potassium (K) - -
Bicarbonate (HCO ) -
Sulphate (SO,) -
Chloride (Cl) -
Fluoride (F) - - -
Nitrate (NO )
Hardness - -
Mg/Li'
37
oft------ 2.O
----- 21
- .5 316
7.6
- 15
.----- 1 Q1 « J
______ oftr
Originally reported in parts per million by Miller
and Arnow (written communication, 1965). Parts
per million is numerically equivalent to milli
grams per 1i ter.
61
Table 13» Chemical analyses reported by Austin, Smith and Associates (196?)
[Collected: August
Airport Colonia
Swamp, (un-
Yap treated)
pH
Turbidity
Alkal i ni ty - CaCO
Chloride ---
1 ron -
Copper ---
Manganese
Sulphate -
Nitrate
Si 1 ica -
Phosphate -
8.0 7.6
0 50
15 30
10 25
8 12
.1 .3
.05 .05
.5 .3
7 134.4
8
3.7
1967. Units reported in parts per mill
Stream Stream
Colonia on on0 /
-(treated) Tamil Gagil
8.5 8.1 8.2
20 0 0
10 30 95
50 10 80
16 10 15
.2 .15 .05
.05 .05 .15
.3 .4 1.2
12 9 11
8.0 35 18
14 20 40
.2 .2 .1
Seep
on
Maap
6.8
15
155
140
25
.8
.1
1.8
17
14
75 .6
I ion]
Seep
on
Rumung
8
10
105
85
25
2
12
25
53
.0
.35
.25
.1
.1
I/ Untreated source of Colonia water-supply system is Tholomar Stream, Yap.
2/ Treatment not specified.
62
Table 14. Chemical analyses made for Lyon Associates (1979)
[Source: Nance, 1979. Samples analyzed by Brewer Analytical
Laboratories, Honolulu, August 31 to September 14, 1979.
Units reported in milligrams per liter]
Chemical constituent
Faraq test
wel1, Yap
Aug. 18, 1979
Monguch Stream,
Gagi1-Tami1
Aug. 19, 1979
Fluoride 0.02
Nitrate nitrogen - - - .14
Cyanide < .01
Sulfate - 3
Total dissolved solids ------------ -_-_ 156
Arsenic - < .05
Selenium -- ----- ----- - ----- -- < .010
Barium -- -------------- ----- -- < 1
Cadmium --- < .010
Chromium - ---- ------------ --------- < .05
Lead .02
Silver < .001
Copper - - -------- . __- ________ .01
Iron ----- -------------- _-----__-_--- .16
Manganese ---- - -_-_ -_- _ ___--- .34
Zinc 1.08
Mercury < .00005
0.01
.05
< .01
4
55
< .05
< .010
< 1
< .010
< .05
.02
< .001
.01
.04
.35
.01
< .00005
63
In 1979) the U.S. Geological Survey began a program to collect and analyze
water samples from all major water sources in the Yap Islands. Results of
chemical analyses made of water from 10 streams on the Island of Yap are
remarkably similar. The chemical analyses of water from one spring and four
streams on Gagil-TamM show more variation. Water from Monguch Stream proved to
be very low in dissolved solids but high in iron concentration. The
concentrations of constituents of ground water in Yap and Gagi1-Tamil Island are
similar to those of the surface water except for a noticeably greater concen
tration of silica and less dissolved iron in ground water. Tables 49-60 in the
Hydrologic Data section list the data obtained thus far at the following
locations:
Table
Gaging stations sites:Qatliw (Atelu) Stream, Yap 49
Qaringeel (Aringel) Stream, Yap ---------------------- - 50
Daloelaeb (Dalolab) Stream, Yap ------------- ------- --- 51
Peemgoy (Pemgoy) Stream, Yap -------------- ____ ____ 52
Taalgum (Talagu) Stream, Yap - ---------- --______ ___ 53
Burong Stream, Yap ---------------- _______________ ___ 54
Mukong Stream, Gagil-Tamil __-_-______-___ ____________ 55
Eyeb Stream, Gagil-Tamil -- ------------------------ - 56
Low-flow partial-record sites:Tamaney Stream, Yap _________-___________-_---_------ 57
Ripu Stream, Yap ------------------ - - - --- __-__- 57
Dinaey (Dinay) Stream, Yap - - 57
Tholomar (Thalomar) Stream, Yap 57
Monguch Stream, Gagil-Tamil - ------------------------ -- 58
Gilaew (Bileiy) Spring, Gagil-Tamil - ------ ------------ 58
Qamin (Amin) Stream, Maap ---- ------------- _______ ___ 58
64
Miscellaneous sites:Dorfay Stream, Gagil-Tamil -- -- - 58
Airport Swamp, Yap ----- -- - - - - - - --- 59
Water treatment plant, Yap - - -- - 59
Timlang 3 well, Yap ----- - - - - - 60
Lamaer wel 1, Yap --- -- - -- - - 60
Communication Station well, Yap - -- -- - 60
Mitsui well, Yap 60
Monguch 1 well, Gagil-Tamil - --- - --- 60
Water temperatures
Stream temperatures do not vary much on the Yap Islands. They fluctuate
somewhat with ambient conditions and are normally highest in midafternoon. Tem
perature is an important consideration because of its effect on chemical
reactions and biological activities.
Water temperatures are normally obtained when a discharge measurement of
streamflow is made. These temperatures are listed in tables 62-81 in the Hydro-
logic Data section.
65
APPLICATION OF DATA FOR FUTURE WATER DEVELOPMENT
Reservoi rs
Population growth and higher per-capita water consumption will increase the
demand for potable water in Colonia. Population is expected to be nearly 2,000
in 1987 (Hawaii Architects and Engineers, Inc., 1968). Not included in this
estimate are those government employees who work and live in Colonia during the
week and live elsewhere on the weekends. Lyon Associates (1980) calculated the
water demand in 1980 as 118,000 gal/d and estimated a demand of 192,000 gal/d in
1990 and 258,000 gal/d in 2000, using the 3.3 percent annual growth rate of the
Quarterly Bulletin of Statistics (Trust Territory of the Pacific Islands, 1979).
A demand to extend the water-distribution system outside Colonia and other
areas that are presently served is anticipated. As saltwater conversion is too
expensive and substantial ground-water development appears difficult, the most
feasible way to increase the public water supply is by surface-water development.
Miller and Arnow (written communication, 1965) evaluated some potential surface-
water sites as follows:
On the basis of the above estimated requirements, (in 1965, it expected that there would be about 3>000 people in the area requiring water service) field investigations were made of several streams that could provide substantially larger supplies than are presently being used. The investigations were mainly in the headwater areas to secure a source of supply for gravity feed to places of use and to greatly reduce the chances for pollution that exist at lower reservoir sites. The sources investigated are described below, and possible dam sites are shown *** (fig. 28).
Mabu Stream. --Mabu Stream heads on the south side of Mt. Matade and drains into Chamorro Bay near Colonia. A dam site was found just below the confluence of two tributaries at about the 50-meter contour. A rough estimate indicates that a dam 30 feet high and 100 to 150 feet long would have a storage capacity of about 20 million gallons.
Pemgoy Stream.--Pemgoy Stream drains the basin immediately west of Mabu. Below its confluence with Talagu Stream at about 25 meters in elevation, it is known as Keyar Stream and flows southeast to Ngolog Bay at Dachngar. A dam site was found at about 35 meters in elevation approximately 500 feet above its confluence with Talagu Stream. A dam at this site approximately 25 feet high and 90 feet long would form a reservoir having a storage capaci ty of about 10 mi 1 1 ion gal Ions. A 35- foot dam about 100 feet long would impound about 20 million gallons.
66
138°05' E 1380 07'30" E
GERMAN DAM (abandoned)
Tabunifi 138°05' E
Figure 28. Map of south central Yap Island showing possible dam sites (written communication, Miller and Arnow, 1965).
67
Talagu Stream. Talagu Stream presented a good potential dam site at an elevation of about 50 meters. Storage behind a 25-foot dam, 80 feet long, would be about 10 million gallons.
Dalolab Stream. Dalolab Stream drains the basin immediately southwest of the Talagu-Pemgoy basin and north of the cross-island road to Kanif. It also flows into Ngolog Bay at Dachngar. A 42,000-galIon temporary water-service storage tank is located on a hill between the road and Dalolab Stream at about 77 meters in elevation. A dam site was found at an elevation of about ^5 meters roughly 1,000 feet north of the water-tank hill. Storage behind a 25-foot dam, 100 feet long, would be about 10 mi 11 ion gal Ions.
To illustrate possible yield from a small dam, mass curves of monthly mean
discharges (1969-79) were drawn for Daloelaeb (Dalolab), Peemgoy (Pemgoy), and
Taalgum (Talagu) Streams. Mass curves are used for storage analyses. Any
desired draft rate can be represented by a straight line of appropriate slope
drawn for the most critical period. The needed storage is indicated by the
maximum vertical distance between the draft rate slope and the mass curve.
Figures 29, 30, and 31 show the maximum draft rate for three streams and the
required storage. No evaporation losses were considered. These would amount to
an average of about half a foot per month (see table 25 in the Hydrologic Data
section).
Because the discharge of the three streams during 1969-79 did not fluctuate
much, practically all flow could have been utilized with the storage and draft
rate shown. As this is the maximum draft rate, any smaller storage with a lesser
draft rate could be designed.
The suitability of water from Daloelaeb, Peemgoy and Taalgum Streams for
domestic use was shown by chemical analyses of the streamflow (tables 51-53, in
the Hydrologic Data section).
Sunn, Low, Tom and Hara, Inc. (1971) proposed a dam below the gaging station
site on Mukong Stream, Gagi1-Tamil. Concluding that development of adequate
ground-water sources would not be feasible, they suggested the following:
Consideration, therefore, is given to the development of surface waters flowing through the large central valley of Tomil. The drainage area is relatively large and the terrain features appear conducive to the construction of a dam which could impound sufficient quantities of water to meet the needs of both Tomil and Gagil.
68
Mean d
isch
arge
, 0.23 M
gal/
d
Draf
t ra
te,
0.22 M
gal/d
with
54
Mgal
(1
66 a
cre-feet), s
tora
ge
Draft
rate
1969
1970
1971
1972
1973
1974
1975
1976
1977
1978
1979
FIGURE 2
9,
MASS C
URVE O
F MEAN M
ONTH
LY D
ISCHARGE F
OR D
ALOELAEB S
TREA
M, Y
AP,
.Mea
n d
isch
arg
e 0.
38 M
gal/d
Dra
ft
rate
, 0.
36
Mga
l/d w
ith
11
0 M
gal
(338
a
cre
-fe
et)
st
ora
ge
1969
1970
1971
1972
1978
1979
FIGU
RE 3
0,
MASS
CU
RVE
OF M
EAN
MONT
HLY
DISC
HARG
E FO
R PE
EMGO
Y ST
REAM
, YA
P,
MEAN MONTHLY CUMULATIVE DISCHARGE, IN MILLION GALLONS PER DAYI 'i ' ho ho v^i v^i -t -t v_n
CD v_n CD
Studies based on U.S. Geological Survey maps indicate that a 10-foot high earthen dam located near Maa 1 village could impound approximately ^.0 million gallons of water, or the equivalent of about 10 weeks storage capacity at present design water consumption rates for Tomi1 and Gagil. The dam would consist of an earth embankment with an impermeable core, a concrete spillway to pass excess flows, and a low level sluice pipe. Initially the dam would span approximately 600 feet, be 10 feet high from the lowest point of the river, and have a top width of 20 feet. The dam height could easily be raised to provide increased storage capacities and to accomodate future water requirements. Initial water treatment facilities could consist of infiltration galleries which would filter the water prior to chlorination. As water consumption increases, water treatment facilities could be modified or expanded to meet increased demands. Gasoline powered pumps will deliver the treated water through transmission mains to reservoirs located in Tomil and Gagil. Two 100,000 gallon reservoirs are proposed, each providing approximately 5 days storage capacity. One reservoir shall be sited on a high point near Tomil School and the other reservoir sited in Gachpar village, Gagil. Transmission lines will then convey water to community distribution facilities in the village.
It should be noted that all recommendations were made before any streamflow
data were available.
Rain Catchments
Although Yapese do not use much water for drinking (coconut water and canned
drinks are preferred), some rainwater always has been collected mainly for food
preparation. Runoff from roofs or palms is stored in cans, bottles, drums, and
various other containers. Because of an average yearly rainfall of more than 120
inches, the use of roofs for rain catchment should provide a good source of
water. However, as the rainfall is seasonal, storage is required for water
during the dry season.
Small concrete reservoirs (usually 6x6x8 feet, with a spigot at the
base) were built in many villages during the Japanese Administration, but few, if
any, are still in use. These reservoirs were filled by rainwater from the roofs
of government buildings.
In Colonia, where most of the larger buildings are, few roofs have been used
for rain catchments. Because of the cost of constructing many separate storage
facilities, their maintenance, prevention of contamination and treatment
required, a public water system is preferred. To provide areas outside Colonia
with a public water system would be difficult, so the supply of water in these
areas will probably come mainly from individual rain catchments or from small
scale local development of spring or streamflow.
72
To project a water supply derived from a roof catchment, mass curves were
drawn for the dry periods during 2 years of average rainfall (1960, 1965) an d for
2 extremely dry years (1966, 1973).
On figures 32-35, the draft rates for these years are shown for a catchment
of 100 ft2 with
100 percent recovery.
Similar determi n
the results are given in tables 15 and 16.
2 area of 100 ft with storage facilities of 100, 200, and 300 gallons, assuming
2 Similar determinations were made for catchment areas of 200 and 300 ft , and
73
1700
1600
1500
1400
1 1300__i__i<:CJ3
s 1200 i ii
I 1100
o o
1000
900
800o o
o 700
600
500
o
300
200
100
0
Rainfall data at Yap Airport January 1 to May 9, 1960
Computations assume catchment is 100 percent efficient
Storage in gallons
100.___L
Storage in gallons
Draft rate in gal/day
January February March April May
TIME IN DAYS
Figure 32. Determination of daily draft rates and storage requirements for rainfall catchment in Yap Islands for the dry period in
a year with average rainfall (1960).
CUMU
LATI
VE RA
INFA
LL ON
100
SQUA
RE-F
OOT
CATC
HMEN
T IN G
ALLONS
CO
C
O
-h o
O
fD-s
c-t
-fD
-s
-s
<<
'
OfD
=5
CU
O-S
CD
O
O"J"
*"
t)
s: o
_i
. rr
Q.
r+ 3
o>
^-
fD
-
-5 i
OJ fD
-"
Q-
-S
=3
-SO
J CU
tQ
^C -
hfD
O
» c+
-s
-sCU
v i
CU-"
CO
<
+rs
'
fD-h
&>
CO
pj
^3-I Q
. C
U-'
to
rs CL
' >
h
H-»
o
to^O
"^
c~
J- C
T)
Ocn
c-h
-s
. CD
C
Q
fD
fD
-S-S
fD
-" -
O
O
C
CL
-
-s-
fD c-
h CO
Rainfall data at Yap Airport January 1 to May 31, 1966
Computations assume catchment is 100 percent efficient
Storage in gallons
Draft rate in gal/day
January February March TIME IN DAYS
Apri 1
Figure 34. Determination of daily draft rates and storage requirements for rainfall catchment in Yap Islands for the dry period in a very dry year (1966).
76
CUMULATIVE RAINFALL ON
100
SQUARE-FOOT
CATC
HMEN
T IN GALLONS
tt>
-"
3 3
rl-
P> rt-
3 O 3
-< CU O
Table 15- Draft rate, in gallons, for available storage for several
catchment sizes during the dry per iod of years with average rainfall
Year
I960
1965
Table 16.
Year
1 966 -(January- May)1973 -
(January- May)
Storage (gallon)
100200 300
100200 300
Draft rate, in gal 1
several catchment
Storage (gal Ion)
100200 300
100200 300
100
7.0 10
8.5 12.5
ons,
Catchment (ft )
200 Draft rate, (gal/d)
10.014.5 18.0 13.0 17.0 21.0
for available storage for
300
11.5 17.0 22.0 15.0 22.0 25.5
sizes during very dry years
100
4.5 5.5 6.5 3.0 4.5 5.5
oCatchment (ft )
200 Draft rate, (gal/d)
6.6 9.0 10.0 5.0 6.5 8.0
300
8.0 12.5 13.5 6.5 8.0 9.5
78
SUMMARY
As the population of the Yap Islands continues to increase and the demand
for water keeps growing, additional sources of water will have to be developed.
The largest amount of water available is from surface water. However, as
all streams on the Island of Yap are dry part of the year, storage facilities
would have to be constructed. Water from these reservoirs would be needed for
the Central Water Supply System in and around Colonia. In a few areas, ground
water would be available for small-scale development and local distribution.
This could be supplemented by water from seeps and small streams and in many
areas on Gagil-Tamil by diversions from some of the perennial streams.
For all areas outside the Colonia Central Water System, individual rain
catchments from the roofs of dwellings should be encouraged. Because no single
water source will be able to provide the needed water supply, it will be
necessary to combine all available sources in each area to meet the demand.
HYDROLOGIC DATA
RainfalI
Page
German rainfall records on
Rumung, 1899-1900 84
Yap Island, 1901-14 84
Japanese rainfall records on Yap Island, 1915-43 - -- - ---- - 85
U.S. National Weather Service rainfall record on Yap Island,
1948-83 - - 86
U.S. Coast Guard rainfall records on Gagil-Tamil, 1969-73, 1976 87
U.S. Geological Survey rainfall records at
Protestant Mission, Colonia, Yap, 1974-76, 1978 88
Taalgum Stream, Yap, 1974-79 89
LORAN station, Gagil-Tamil, 1981-83 91
Evaporation
Evaporation data for Guam (1956-82) and Yap (1978-82) 93
Air Temperatures
Air temperatures on Yap Island
1921-50 94
1951-81 - - - 95
80
Streamflow Records
Gaging stations
In tables 28-36, peak discharges, annual minimum discharges, and
annual discharges are given for the following gaging stations:
Page
16892000 Qatliw (Atelu) Stream, Yap, 1982 96
16892400 Qaringeel (Aringel) Stream, Yap, 1968-82 98
16892800 Daloelaeb (Dalolab) Stream, Yap, 1968-81 103
16892900 Peemgoy (Pemgoy) Stream, Yap, 1968-82 108
16893000 Taalgum (Talagu) Stream, Yap, 1968-79 11316893100 Burong Stream, Yap, 1968-82 118
16893200 Mukong Stream, Gagil-Tamil, 1974-82 123
16893300 Gilaew (Bileiy) Spring, Gagil-Tamil, 1968-74 128
16893400 Eyeb Stream, Gagil-Tamil, 1982 130
Low-flow partial-record stations
In tables 37-47, the discharge measurements made at the following
low-flow partial-record stations are listed:
16892450 Faraq (Fara) Swamp outlets, Yap, 1968-73 13216892460 Galngun Swamp outlet, Yap, 1968-73 133
16892500 Tamaney Stream, Yap, 1968-82 134
16892600 Ripu Stream, Yap, 1968-82 135
16892650 Dinaey (Dinay) Stream, Yap, 1980-82 136
16892700 Tholomar (Thalomar) Stream, Yap, 1965, 1968-74, 1980-82 137
16893050 Mabuuq (Mabu) Stream, Yap, 1968-72 138
16893180 Monguch Stream, Gagil-Tamil, 1979-82 139
16893310 Gilaew (Bileiy) Stream, Gagil-Tamil, 1968-80 140
16893350 Yanbilang Stream, Gagil-Tamil, 1968-72 141
16893500 Qamin (Amin) Stream, Maap, 1980-81 142
Miscellaneous measurements
Discharge measurements made at miscellaneous sites -------------
81
Water Qua! i ty
Chemical analyses
Tables 49-60 list the physical properties and constituents of water
samples collected and analyzed by the U.S. Geological Survey during 1979-82
for the following locations:
Page
16892000
16892400
16892500
16892600
16892650
16892680
16892800
16892900
16893000
16893100
16893180
16893190
16893200
16893300
16893^00
16893500
Qatliw (Atelu) Stream, Yap
Qaringeel (Aringel) Stream, Yap
Tamaney Stream, Yap 152
Ripu Stream, Yap 152
Dinaey (Dinay) Stream, Yap 152
Tholomar (Thalomar) Stream, Yap 152
Daloelaeb (Dalolab) Stream, Yap 146
Peemgoy (Pemgoy) Stream, Yap
Taalgum (Talagu) Stream, Yap
Burong Stream, Yap
Monguch Stream, Gagi 1 -Tamil 153
Dorfay Stream, Gagi 1 -Tamil 153
Mukong Stream, Gagi 1 -Tamil 150
Gilaew (Bileiy) Spring, Gagil-Tamil 153
Eyeb Stream, Gagil-Tamil 151
Qamin (Amin) Stream, Maap 153
Water-treatment plant, Yap ---------------------------
Airport Swamp, Yap --------- ______________________
Timlang 3 well, Yap - - 155
Lamaer well, Yap - - 155
Communication Station well, Yap ------ _______ _____ 155
Mitsui well, Yap 155
Monguch 1 well, Gagil-Tamil 155
82
Water temperatures
Water temperatures and instantaneous discharge obtained at the following
gaging station and low-flow partial-record station sites are given in tables
62-81. Concurrent air temperatures are listed where available.
Page
16892000 Qatliw (Atelu) Stream, Yap 157
16892400 Qaringeel (Aringel) Stream, Yap 157
16892450 Faraq (Fara) Swamp outlets, Yap 160
16892460 Galngun Swamp outlet, Yap 160
16892500 Tamaney Stream, Yap 161
16892600 Ripu Stream, Yap 162
16892650 Dinaey (Dinay) Stream, Yap 163
16892680 Tholomar (Thalomar) Stream, Yap 164
16892800 Daloelaeb (Dalolab) Stream, Yap 165
16892900 Peemgoy (Pemgoy) Stream, Yap 167
16893000 Taalgum (Talagu) Stream, Yap 170
16893050 Mabuuq (Mabu) Stream, Yap 172
16893100 Burong Stream, Yap 173
16893180 Monguch Stream, Gagil-Tamil 176
16893200 Mukong Stream, Gagil-Tamil 176
16893300 Gilaew (Bileiy) Spring, Gagil-Tamil 180
16893310 Gilaew (Bileiy) Stream, Gagil-Tamil 182
16893350 Yanbilang Stream, Gagil-Tamil 183
16893400 Eyeb Stream, Gagil-Tamil 184
16893500 Qamin (Amin) Stream, Maap 184
83
Table 17- Monthly and annual rainfall, in inches, during the German Administration
[Converted from mi 11imeters to inches]
Rumung
Source: "Mittheilungen von Forschungreisenden und Gelehrten aus den deutschen Schutzgebieten", 1901.
i fioo
1900
Jan.
2.4
Feb.
1.0
Mar.
1.0
Apr. May
1.4 2.1
June July
5.9 1/15.1
Aug.
1/18.7
Sept.
1/12.3
Oct.
1/21.2
Nov.
1/16.6
Dec.
4.1
Annual
(109.4)
Yap Island
Sources: "Mitt(h)eilungen von Forschungreisenden und Gelehrten ausden deutschen Schutzgebieten"; annual publications 1902, 1913.
"Strategic Bulletins of Oceania" no. 7, publication of Institute ofHuman Relations, Yale University, 1943.
Government of the Philippine Islands, Weather Bureau. Manila Central Observatory; annual summaries 1913-14.
190119021903190419051906190719081909 1910191119121913
191^
MeanYears
Jan.
9.515.22.28.62.63-85.913.6
1.72.61.5
2.2
5.812
Feb.
17.122.61.55.14.6 13.04.4
8.52.63.3
9-0
8.311
Mar.
8.113-91.4
13.32.6 11.413.1
17.11.01.9
3-7
8.011
Apr.
5.85.35.712.82.5 .3
5.0
6.73.09.02.6
5.311
May
9.412.36.112.47.414.87.28.8
9.58.94.2
5.3
8.912
June
7.59.211.212.217.49.512.513.8
7.75.73. A
7.7
9.812
July
12.118.415-54.819.512.08.69.6
45.916.416.9
10.9
15.912
Aug.
17.919.411.116.917.510.422.219.6
14.415.417.4
10.6
16.112
Sept.
6.715. ̂13.628.213.214.414.610.5
10.312.914.5
8.1
13.512
Oct.
25.04.022.310.112.57.68.7~
n.712.614.7
^5.4
12.211
Nov.
11.04.219.07.36.915-49.6
2.912.71.2
i/4.4
8.611
Dec.
7.93-916.22.59.112.814.2
4.86.95.1
^3.0
7.911
Annual
138.0143.8125.8134.2115.8 128.2
141.2100.793.1
72.9
119.410
2/
Publications do not report date of change of location to Yap Island. Name of observer from June 22, 1900 is the same as for 1901, 1902. For 1901, latitude and longitude were given for the Yap Island location.
October to December 1914 included in German period although the Yap Islands were already occupied by Japan.
Table 18. Monthly and annual rainfall, in inches, during the Japanese Administration
[Converted from mi 11imeters to inches]
Sources: Government of the Philippine Islands, Weather Bureau, Manila CentralObservatory; annual summaries, 1915-20.
"World Weather Records," publication of Smithsonian Institution,(1921-30), and 19^7, (1931-40).
U.S. Weather Bureau, 1959 (1941-43).
19151916191719181919192019211922192319241925192619271928192919301931193219331934193519361937193819391940194119421943
MeanYearsPercent
Jan.
3.213-98.7
10.32.59.23.89.1
11.42.63.6
18.15.03-9
16.76.05.35.42.36.97.84.93.38.0
10.15.84.66.0
19.3
7.529
6.1
Feb.
0.717.64.27.62.39.51.62.86.21.23.83.7
13.04.85.84.51.67.17.76.44.41.83.23-25.56.82.41.25.5
5.029
4.1
Mar.
2.912.06.84.12.43-7 8.46.61.01.42.13.64.2
.81.31.0
10.43.57.35.78.55.5^.72.95.73.02.24.5
4.528
3.6
Apr.
2.87.72.8
12.72.42.89.23.05.13.14.6
.25.05.7
10.63.43.02.67.77.96.94.46.48.37.6
15.21.05.*9.5
5.829
*».?
May
11.913.212.23.77.88.6
13.25.3
11.08.78.12.68.7
19.38.18.49.2
15.88.97.0
10.214.66.5
12.19.8*».9
12.17.69.9
9.629
7.8
June
15.615.87.9
2/8.5^4.4
10.57.89.1
20.89.48.9
10.69.6
13.45.2
16.15.97.96.79.06.98.5
10.211.94.4
16.515.06.5
15.3
10.329
8.4
July
12.29.5
13.919.616.731.18.7
11.824.919.722.013.525.716.615-926.99.5
21.114.514.615.320.210.814.315.524.414.217.918.5
17.229
13.9
Aug.
18.89.89.0
17-919.111.810.919.128.111.620.222.225.56.6
16.316.914.37.88.8
25.08.6
22.419.08.1
14.732.120.419.011.2
16.429
13.3
Sept.
5.817-717.58.0
10.48.1
10.719.312.211.48.3
16.47.7
18.610.619.015.218.79.5
15.620.315.911.220.416.514.512.213.916.2
13.929
11.3
Oct.
12.815.38.38.7
11.610.310.25.77.<»
15.222.617.18.6
11.414.46.7
22.99-5
24.011.19.9
14.617.712.617.86.83.7
12.210.9
12.429
10.0
Nov.
8.413.311.77.7
10.18.9
13.98.87.2
22.57-99-9
13.210.09.19.0
19. *»6.7
10.71*.712.73.68.0
10.117.38.6
11.05.2
14.4
10.829
8.8
Dec.
14.46.49.45.96.8(3)
12.210.16.5
V 13.8-'14.3
6.612.92.26.2
19.410.918.810.28.06.86.65-9
23.15.47.67.<»
10.48.2
9.928
8.0
Annual
-^og^152.2112.42 m.7
-7 96.5
112.5147.4120.2125.7123.0138.6116.7119-7137.6118.2131.8114.5133.5115-5126.0107.7136.8127.5148.9107.0107.5143.4
123.927
1 day mi ssing.2/ 4 days missing.
(3) Rain gage destroyed by typhoon of Dec. 17, 1920.4/ Rain gage destroyed by typhoon of Dec. 15, 1925 after 2 p.m..
Total of monthly means: 123.3 inches.
Replaced on Dec. 16.
Table 19- Monthly and'annual rainfall, in inches, for the period 1948-83
Obtained by U.S. Navy during 1948-51 and by National Weather Service since 1952 (U.S. National Oceanic and Atmospheric Administration, 1981, 1982-83).
Location: 1948 to March 1968, lat 9°31', long 138°08' (next to Raiview Hotel).
Location: March 1968 to present, lat 9°29', long 138°05', altitude 44 ft, at Yap Airfield. A 4-inch rain gage was used to Dec. 31, 1953 and an 8-inch gage thereafter.
Year
19*819491950195119521953195419551956195719581959196019611962196319641965196619671968196919701971197219731974197519761977197819791980198119821983
1949-82:Mean
Jan.
8.246.925.864.214.032.97
23.087.7815.1013.707.757.7811.658.5311.262.373-324.9812.0210.774.104.6410.426.032.1411.8419.487.363-944.223.882.3212.907-301.25
8.03Percent 6.6
Feb.
3.991.08
10.843.279.371.934.863.634.701.467.996.235.6613.3612.206.476.001.296.258.041.246.1710.1110.421.004.271.203-192.185.253.164.608.0012.58
.27
5.654.6
Mar.
4.1916.463.461.497.872.372.228.746.531.389.074.2211.157.8211.134.017.632.315.373.722.084.6713.4814.211.549.993.128.762.422.047.066.422.897.502.76
6.165.1
Apr.
__5.184.253.976.828.222.017.9818.155.272.924.386.304.7515.954.207.614.251.86
11.761.823.033.0412.258.975.6210.0710.736.77O.gi5.383.987.721.102.621.36
6.175-1
May
6.625-757.9811.496.6112.9312.2912.176.164.6811.5412.7018.0814.437.1418.238.126.7116.003.947.699.7612.845.335-989.779.0912.5210.364.878.8210.575.0510.493.59
9.607-9
June
11.4412.373.4020.7520.279.9111.1811.4511.4810.214.699.4612.337.968.776.7410.8812.5216.715.768.788.7613.9410.1812.3514.3010.6713.307.4912.8921.0713.5210.7732.01
12.019.9
July
4.998.9210.8512.786.517.3312.9919.5613.8215.8418.9511.4512.7019.4413.499.4426.4717.9814.1414.2434.718.8014.129.2010.1114.408.3811.4317.218.6714.4417.8418.5413-04
13.9111.4
Aug.
7.6210.5516.4715.8129.448.81
20.0111.4111.806.0711.6111.9617.2517.3228.2016.7212.399.0216.4510.9011.5825.4512.1511.095.1312.3311.9016.2913.9918.5219.579.5213.6114.26
14.2711.7
Sept.
11.7919.5714.8512.5815.676.889.7414.7212.1317.6012.8011.1810.6315.1012.2310.2512.5517.739.5911.7210.6617.0311.0413.8717.6017.649.4811.2513-4418.7319.179.5912.7119.0313-93
13.6011.2
Oct.
11.4615.3912.1110.3017.7714.2014.0615.3514.269.339-7411.6118.0721.169.6516.6711.698.427.1112.8011.2111.4812.3115.155.6414.9219.1112.672.595.7618.1012.1813.4114.229.34
12.5810.3
Nov.
13.036.0915.596.657.8014.6513.099.9511.971.96
18.5310.3420.664.427.417.476.1912.028.8410.443.599.769.5610.269.3510.5718.856.798.889-4711.097.347.2010.124.95
9.768.0
Dec.
15.657.5311.2812.457.4612.2717.0512.3214.273.655.2011.168.1311.2715-0110.1710.983.699.977.488.348.328.159.715.147.0313.3010.939.9711.648.9813.4014.5211.017.01
9-968.2
Annual
__100.85120.13104.81125.32140.32102.20146.95145.52109.40102.53120.27127.59145.52149.11140.95113.00120.9292.18141.1492.99119.80112.35148.30113.1694.03147.71116.21114.50104.10119.18124.49120.35127.24135.03
121.70100
86
Table 20. Mean monthly rainfall, in inches, for a period of 27-28 years
prior to 1938 (years not identified)
Location: Lat 9°30' N., long 138°08' E.
Source: "Sailing Directions for the Pacific Islands," U.S. Navy
Department, Hydrographic Office, 1938.
Jan. Feb. Mar. Apr. May June July Aug. Sept. Oct. Nov. Dec. Annual
6.5A 5.89 A.98 5.11 9.99 9-89 16.88 16.35 12.54 11.81 9.97 9.08 119.03
Table 21 Monthly and annual rainfall, in inches,
at Gagi 1 -Tami 1
Source: U.S. Coast Guard
Year
196919701971197219731976
Year
196919701971197219731976
July
23.3810.7020.5011.54
9. A3
Jan.
A. 68A. 229.65
1.11 ~
Aug.
12.30* A. 1014.0114.95
14.11
Feb.
2.325.0010.29 1.09
Sept.
11.91* 5.2210.3422.49
12.75
, 1969-73, 1976
LORAN station, Gagi 1 -Tamil
Mar. Apr. May
2.30 4.38 13.464.55 4.06 11.9411.95 10.29 16.999.52 8.60 2.61
5.18 8.96 12.64
Oct. Nov.
12.25 12.08* 4.82 * 5.8215.30 9.206.02 6.15
3.03 7.12
June
9.4211.5613.3810.65
14.91
Dec.
10.787.585.495.11
12. 6A
Annual
119.26* 79.561A7.39
-- ~"~"
* Appears incorrect.
87
Table 22. Cumulative rainfall readings, in inches, at Protestant Mission,
Colonia, Yap
[Lat 9°30'W N., long 138°07'29" E., near front of Mission Church in Colonia; altitude, 25 ft (from topographic map)]
Period Rainfal1 Per iod Rainfal1
Apr. 6-23 14.2May 9-16 2.8May 16 to June 11 9.6June 11 to July 11 11.2
Apr. 26 to May 5 - May 5-1 1* May 14 to June 18 June 18 to July 14 July 14-29 July 29 to Aug. 15
Dec. Jan. Jan. Feb. Feb. Mar. Mar. Apr. Apr.
23 to Jan. 9 9-27 - 27 to Feb. 4
18 to Mar. 2 2-11 - 11 to Apr. 2 2-20 20 to May 3
May 3-20
3Jan. 19 to Feb. Feb. 3-23 Apr. 1-12 May 5-26 May 26 to June 16 June 16-29
6.2.8
8.08.71.8
11.0
1.72.71.205.01.04.52.31.6
11.1
1.5 1.1
4.0 3.2 6.2 7.5
June 29 to July 25 5.6
1974
July 11-30 7.2Sept. 14 to Oct. 10 7.8Oct. 10 to Nov. 6 17.2Nov. 6 to Dec. 6 11.2
1975
Aug. 15-28 Aug. 28 to Sept. 22 Sept. 22 to Oct. 9 Oct. 9 to Nov. 5 Nov. 5 to Dec. 14 Dec. 4-23
1976
May 20 to June 16 June 16 to July 6 July 6-27 July 27 to Aug. 11 Aug. 11-27 Aug. 27 to Sept. 17 Oct. 10 to Nov. 2 Nov. 2 to Dec. 3 Dec. 3-30
1978
July 25 to Aug. 30 Aug. 30 to Sept. 19 Sept. 19-29 Sept. 29 to Oct. 31 Oct. 31 to Nov. 30 Nov. 30 to Dec. 12 Dec. 12-28
2.0 5.9 5.2 7.1 6.1 4.0
8.413.011.06.57.210.91.1
10.9 5.2
18.314.52.816.67.75.8.2
88
Table 23. Cumulative rainfall readings, in inches, at Taalgum Stream,
[Lat 9°31'02" N., long 138°06'33" E., on hillside along foot trail to Taalgum River gaging station; altitude, 200 ft (from topographic map)]
Per iod Rainfal1 Per iod Rainfal1
1974
nay o-i/ May 17 to June 11 --June 1 1 to July 1 1 -July 11-30 ------------
Jan. 1-12 Apr. 26 to May 5 ------May 6-14 ----- May 14 to June 17 -----June 17 to July 14 July 14-29 July 29 to Aug. 14
Dec. 23 to Jan. 9 Jan. 9-27 Jan. 27 to Feb. 3 -----Feb. 3-17 Feb. 17 to Mar. 2 Mar. 2-11 Mar. 11 to Apr. 2 Apr. 2-20 Apr. 20 to May 3 ------May 3-20 May 20 to June 16
Dec. 30 to Jan. 21 June 7 to July 1 ----July to Aug. 16 -----Nov. 3-16
.5.^ 11.612.06.5
1.25.31.5
10.512.01.1
12.8
1.53.31.607.04.05.08.02.111.07.9
2.24.8
21.14.4
1975
Sept. 12 to Oct. 10 Oct. 10 to Nov. 7 Nov. 7 to Dec. 12 Dec. 12-31
Aug. 14-28 Aug. 28 to Sept 22 - Sept. 22 to Oct. 9 - Oct. 9 to Nov. 5 Nov. 5 to Dec. 4 Dec. 4-23
1976
June 16 to July 6 - July 6-27 July 27 to Aug. 11 -Aug. Aug. Oct. Nov. Dec,
Total
11-27 27 to Sept. 17 10 to Nov. 2 - 2 to Dec. 3 3-30
1977
Nov. 16-30 -Nov. 30 to Dec.Dec. 16-29
16 -
7.517.011.86.5
1.65.9 4.2 8.06.7 4.4
7.69.1 7.8 9.0 9.7 4.7 10.5 9.5
119.3
8.2 8.4 3.0
89
Table 23. Cumulative rainfall readings, in inches, at Taalgum Stream Continued
Period Rainfal1 Period Rainfal1
1978
Jan. 19 to Feb. 3 Feb. 3-23 Feb. 23 to Mar. 16 Apr. 1-12 May 5-26 May 26 to June 16 June 16-29 June 29 to July 25
Dec.Jan. Feh1 W k/
Feb. Mari to i
Maw
28 to 18-301^-2828 to 16-29
17-11 .
Jan.
Mar.
18
16
May 31 to June 13 June 13-29 June 29 to July 11 July 11-26
1.8 3.2 1.25.0
5.1 6.3 7.0
5.01.61.05.401.84.19.510. 43.2
1979
July 25 to Aug. 30 21.2Aug. 30 to Sept. 19 14.9Sept. 19-29 3.2Sept. 29 to Oct. 31 16.1Oct. 31 to Nov. 15 6.5Nov. 15-30 3.6Nov. 30 to Dec. 13 5-9Dec. 13-28 1.2
July 26 to Aug. 8 7.1Aug. 8-21 10.9Aug. 21 to Sept. 5 3.7Sept. 5-19 1.2Sept. 19 to Oct. 5 14.1Oct. 5-30 6.1Oct. 30 to Nov. 19 5.8Nov. 19 to Dec. 4 ----- 2.1Dec. 4-28 12.0
90
Table 2k. Daily rainfall, in inches, at continuous-record rain gageat LORAN station, Gagil Tamil
Uat 9°32'52" N., long 138° station administration building;
1981Day Dec. Jan. Feb. Mar. Apr.
12345678910111213141516171819202122232k25262728293031
Total
_
0.67.38
0.k2.52.07.68
0.11.06.Ok
00.05
0.02.07
3.31.19.80.04
00000
(8.5)
0.410000000.41.70.16
00000.17.08
0000.59
4.840000000
7.36
000.68
1.692.90.01.65.01
00002.75000.10.08.32
0.01.32.02.03
1.1500
10.72
00.01.05
0.31*********.41
(7.0)
..
0.41.01
0000.88
0000.28.01
0000.36
000
(3.2)
1982
10'09" E. altitude,
, in front of the LORAN 70 ft (from topographic map)]
May June July Aug. Sept. Oct. Nov. Dec.
0.06.35.01
0.01.46.30
0.36
0.22.08.05.17
1.541.69.10
1.500.10.08
00000.28.06
0.08.05
7.55
0.0500.07
00.55.05.08
2.020000.02
1.75.89.06.28
7.08**********
*
******
22.52.47.04.19.48.32.02
04.691.130.40.22
1.20001.37.10.40.11
00.06
00
(46.62)
0.47000.07
0.40
00.40.04.06
0.49
1.093.20.06
01.68.62
1.60.55.07
00.82
1.45.95
1.311.54.12
16.99
0.01.25.20
01.14.48.96
000002.541.99.17
0000000001.67.08.05.24
01.31
11.09
1.20.67
0.11.29.48
1.14.68.72.07
0.01.48
000.66.64.07.38.11
0.65.25
0000.06
0.59
9.26
0.37000.01.05
01.140.36
00.49.12.25.10
00000.84.04
0.11.02.01.01.26.82
5.00
0.07.01
00.62.79.25.49.55.71.86.19
1.130000000000.60
0000.02
00
6.29
* Included in following total.Recorded rainfall June 20 (1300) to June 21 (0600): 15.48 inches (June 21, 0000-0600,
8.64 inches). Rainfall at Yap airport: June 21, 13-17 inches; June 21-30, 17.93 inches;July 1-7, 3-13 inches.
No rainfall record December 1-4, 1981 and March 17 to April 9, 1982. Rainfall estimatedon basis of rainfall at Yap airport.
Total for 1982: 131.08 inches.
91
Table 24. Daily rainfall, in inches, at continuous-record rain gage
Year
12345678910111213141516171819202122232425262728293031
Total
at
Jan.
0.10.01
000.05
000000000.22.11.04
0000000.17
00000
0.70
LORAN
Feb.
0000000000.07.02
00000000000000.10
0
0.19
station,
1983
Mar.
00.06
000000000000.02
0000000000002.10.06
0
2.24
Gagi
Apr.
0000.05
0.12
000000.02.01.17.01.05
0000000.02
0000
0.45
1-Tomi 1
May
0.05
0.02.02
00.02.29
0000000000.32
00001.20.31
00.12.70
0
3.05
Continued
June
001.27000000.96.13
00.84.02.19
0.12.70***j.j.***
2.83.35.52
7.93
July
0.02.29
1.10.84.23.11.18.20
92
Evaporation
Table 25. Monthly and annual evaporation data for Guam and Yap
[Source: U.S. National Oceanic and Atmospheric Administration, 1956-72, 1973-82]
Year Jan. Feb. Mar. Apr. May June July
Evaporation data for Guam(January 1956 to
195619571958
1959I9601961196219631964196519661967196819691970197119721973197 A19751976197719781979198019811982
Mean
6.83 6.546.18 5.997.48 6.08
5.63 6.66A. 86 6.264.27 5.736.15 4.944.73 4.315-91 6.395.35 6.317-07 6.555.18 5.325.89 6.315.574.68 5.904.61 6.216.55 6.655.94 5.465.81 6.626.13 6.806.27 5.586.64 6.497.30 6.107.26 6.687.73 6.435.54 7-22
6.20
5.98 6.14
Aug. Sept. Oct. Nov. Dec. Annual
(in inches)May 1958 at Fena Lake, August 1958 to present at Weather
8.247.327-65
7.607.056.277.816.447.018.587.785.328.508.467.936.415.757.476.908.087.228.209.467.767.858.947.64
7.87
9.138.429.34
7.588.057.006.176.576.99
9.176.077.578.968.986.657.858.468.278.357.629.037-729.507.938.138.28
7.99
8.82 7.818.71 9.109.49
9.03 7.967.17 6.546.87 5.577.00 5.206.21 5.376.76 7.47
8.88 7.377.00 5.437.58 5.898.04 8.068.06 7-308.77 6.038.06 7.268.14 6.497.21 5.889.01 9.297.37 7.658.48 7.898.85 6.5510.33 8.448.05 6.916.80 7.148.06 6.90
8.03 7.02
Evaporation data
19781979198019811982
Mean
Totals
6.52 6.745.41 6.163.99 5.566.58 5.60
5.62 6.02
7.496.967.487.12
7.26
of monthly means:
8.216.877.697.56
7.58
Guam 76
7.41 5.906.32 5.978.41 4.365.58 5.70
6.93 5.48
.98, Yap 75.15
5.747.41
6.985.415.084.995.096.187.357.215.065.775.746.275.385.665.46
6.186.597.835.906.446.336.785.89
6.11
for Yap
5.585.556.255.316.82
5.90
inches.
5.867.76
5.485.314.714.674.915.824.756.754.714.714.955.674.285.915.004.795.095.696.336.996.106.344.846.556.28
5.56
4.496.52
5.614.524.384.444.284.294.584.594.764.644.494.904.865.785.875.645.616.145.475.245.335.265.147.386.60
5.22
5.015.57
6.085.124.304.635.005.264.735-565.364.605.534.554.625.745.555.336.285.707.365.536.325.165.987.015.27
5.45
Service station)
5.267.28
4.644.595.035.074.455.115.955.815.395.724.325.095.805.594.716.265.736.736.436.275.465.937.106.666.08
5.65
5.927.22
5.304.895.164.965.26
6.505.885.925.675.355.786.027.315.675.296.936.396.566.905.956.366.205.156.31
5.96
79.6587.48
75.8768.9264.5666.16
73.22
80.1764.7272.15
74.7074.3974.5874.73
84.4980.4585.4981.0485.4680.4983.30
76.76
(in inches)
6.706.335.966.657.75
6.68
5.156.154.787.015.70
5.76
5.338.606.545.565.88
6.38
5.066.T15.244.915.76
5.42
7.236.115.555.356.37
6.12
__81.1272.0172.2876.42
75.46
93
Air Temperatures
Table 26. Monthly and annual mean air temperatures for Yap (1921-50)
Sources: "World Weather Records," publication of Smithsonian Institution, 1934 (1921-30), and 1947 (1931-40). U.S. Weather Bureau, 1959 (1941-50).
Temperature in °C
Year
19211922192319241925192619271928192919301931193219331934193519361937193819391940194119421943194819491950
Jan.
_26.426.526.227.026.426.926.926.126.826.427.026.627.226.426.626.726.926.626.926.526.526.5
26.727.8
Feb.
__26.726.326.526.926.626.627.026.026.526.026.226.526.726.826.626.626.726.726.326.426.926.7
27.127.7
Mar.
_26.926.726.827.226.927.327.326.627.426.626.526.927.027.026.926.726.926.927.026.927.226.7
27.627.8
Apr.
27.427.327.227.327.827.427.626.827.627.527.027.327.227.327.227.227.227.427.027.627.327.0
28.328.3
May
*» »
27.427.027.227.228.327.427.427.027.827.927.027.427.527.527.027.527.027.327.727.627.427.2
28.128.2
June
^^27.126.727.227.427.827.327.127.527.727.927.227.327.327.627.427.227.027.827.527.227.626.8
27.727.8
July
27.026.526.426.726.527.127.027.126.427.427.626.826.826.926.926.827.127.126.826.826.726.326.8--
28.027.7
Aug.
26.826.426.027.026.626.626.427.326.527.827.027.027.126.927.326.826.927.227.126.726.426.526.6
27.427.9
Sept.
26.726.726.826.927.126.7
26.626.627.927.226.627.027.126.927.026.926.726.826.927.026.727.027.427.427.6
Oct.
27.027.227.026.726,627.0
27.026.928.626.827.526.527.227.127.127.026.927.127.327.226.927.027.127.627.6
Nov.
26.927.026.826.727.027.227.227.026.828.126.827.226.826.827.127.427.227.027.027.227.327.126.927.228.327.7
Dec.
26.627.026.926.8
27.327.227.026.627.027.126.826.926.926.927.227.326.527.126.926.826.927.026.827.927.3
Annual
_26.926.726.8
27.1
27.126.627.527.126.926.927.127.127.027.026.927.027.027.026.926.9
27.727.8
Table 27. Monthly and annual mean air temperatures for Yap (1951-81)
Source: U.S. National Oceanic and Atmospheric Administration, 19&1.
Temperatures converted from °F to °C
Year
195119521953195419551956195719581959I9601961196219631964196519661967196819691970197119721973197^1975197619771978197919801981
1922-81:Mean
MaximumYear
Mini numYear
Jan.
27.326.927.427.226.526.826.826.827.427.427.027.126.826.927.326.426.626.626.727.126.826.826.526.326.726.226.726.826.927.126.5
26.9
27.81950
26.11929
Feb.
27.326.827.127.527.127.326.726.927.227.427. 427.126.726.726.926.826.826.726.627.227.126.827.327.227.126.626.926.526.826.826.7
27.0
27.71950
26.019291931
Mar.
27.227.427.527.627. 427.227.427.427.727. 427.327.227.227.126.626.926.727.326.927.527.526.927.627.127.126.627.427.327.027.227-0
27.3
27.81950
26.51932
Apr.
28.028.227.728.427.927.327.727.727.827.827.827.027.627.427-327.827.127.227.627.827.327.328.127.327.126.627.927.627.627.627.7
27.7
28.41954
26.61976
May
27.728.128.427.627.627.628.228.127.827.827.327.427.627.327.827.927.527.727.427.627.227.227.927.127.127.227.327.927.527.628.1
27.7
28.41953
27.019231929193219361938
June
27.927.427.627.827.627.728.428.128.227.727.127.427.727.227.227.627.227.327.727.726.927.427.626.826.626.727.327.427.427.227.0
27.4
28.41957
26.61975
July
27.628.128.127.827.627.727.327.327.227.726.727.127.227. 426.127.327.127.026.927.626.628.327.227.126.826.426.727.426.727.026.7
27.3
28.31972
26.11965
Aug.
27.427.427.127.827.327.627.728.026.927.226.826.827.127.127.127.327.026.926.927.026.827.227.227.326.426.427.126.926.827.427.0
27.2
28.01958
26.01923
Sept.
28.027.427.827.727.827.427.827.427.227.627.027.327.427.627.127. 527.627.126.727.227.127.227.027.026.526.426.826.827.426.827.5
27-3
28.01951
26.41976
Oct.
27.927.827.827.627.327.427.927.927.626.826.627.827.127.527.427.927.426.927.227.326.727.426.726.927.027.327.426.627.227.227.3
27.3
28.61930
26.51933
Nov.
28.128.027.327.427.627.428.127.427.927.726.727.627.527.627.227.627.227.327.127.427.027.227.327.127.127.027.327.227.427.127.4
27.4
28.319^9
26.719241961
Dec.
27.327.727.326.827.427.127.627.927.627.027.126.627.327.127.326.926.926.927.127.327.227.126.927.026.626.727-127.326.926.927.6
27.2
27.91949
26.51938
Annual
27.627.627.627.627.427.427.627.627.527.427.127.227.327.227.127.327.127.127.127.427.027.227.327.026.826.727.227.127.227.227.2
27.3
28.610/1930
26.08/19232/19292/1931
95
Streamflow records
Gaging stations
Table 28. Streamflow records of Qatliw Stream, Yap (16892000)
(Formerly published as Atelu Stream, Yap)
Location; Lat 9°32'58" N., long 138°06'41" E., 90 ft downstream from confluence
with major tributary, 0.4 mi northeast of Bael School and 0.5 mi upstream
from mouth.2 Drainage area: 0.31 mi .
Period of record: Occasional low-flow measurements water years 1980-81.
Continuous record February to September 1982.
Gage: Water-stage recorder arid concrete control. Altitude of gage is 35
ft (from topographic map).
Remarks: Records good. No diversion above station.
Extremes for period of record: Maximum discharge, 87^ ft /s June 21, 1982
(gage height, 5.96 ft), from rating curve extended above 9.9 ft /s on
basis of estimate of peak flow; no flow for several days.
A. Discharge measurements, in cubic feet per second
0.2 mi upstream from mouth Date Discharge
At gaging station, 0.5 mi upstream from mouth
Date Discharge
Sept
Oct.
Mar1 IO 1 .
rApI .
July
June
lul w
. 20
21,
25,
21,
1 ft10,
iJi
, 1980 1980
1981
1981
1981
1982
IQfiO --- __
0
6
0
0
3
.18
.7
0. L.
nft
July
Dec.
Jan.
Feb.
1 la I .
June
l,,l w
21,
31,
12,
*^ 9
i ftlo,
iTi
1981
1981
1982
1 rtO *iI9o2
1982
1982
lafio ___
1. 1/!/'
2.
2
01
01
05
24
7 nc
Estimated.
96
Table 28. Streamflow records of Qatliw Stream, Yap Continued
B. Monthly discharges, in cubic feet per second
Year
1982 Total
MeanMax.Min.
Feb.
48.20
1.7215
.03
Mar.
15.42
.5010
.01
Apr.
0.59
.020
.050
May
13
40
.67
.44
.3
June
230.98
7.70106
0
July
50
117
.42
.63
.02
Aug.
69.71
2.2515
.02
Sept.
45.19
1.5114
.01
Peak discharges above base (200 ft3/s): Feb. 6 (0800) 385 ft^/s (4.30 ft);
June 21 (0445) 874 ft 3 /s (5.96 ft).
97
Table 29. Streamflow records of Qaringeel Stream, Yap (16892^00)
(Formerly published as Aringel Stream, Yap)
Location; Lat 9°31 I 02 11 N., long IBS^S'BI" E., on right bank at Qaringeel
and 0.3 mile southwest of Dalipeebinaew School.2 Drainage area: 0.24 mi .
Period of record: April 1968 to September 1982.
Gage; Water-stage recorder and concrete control. Altitude of gage is
15 ft (from topographic map).
Remarks; Records fair. No diversion above station.
Average discharge; 14 years, 1.12 ft^/s (811 acre-ft/yr).
Extremes for period of record; Maximum discharge, 6jk ft /s July 13>
1981 (gage height, 7.82 ft), from rating curve extended above 20
ft /s; no flow for many days most years.
Discharge measurement made prior to beginning of continuous
discharge record
Oct. 9, 1967 0.10 ft3 /s
98
Table 29. Streamflow records of Qaringeel Stream, Yap Continued
A. Annue.1 maximum discharge (*) and peak discharges above base (200 ft /s)
Date
Sept
JulyJulyJulyAug.Sept
Oct.Aug.Aug.Aug.Aug.Sept
Oct.Jan.Apr.JulyAug.Sept
Mar.SeptSept
Sept
JuneJuneJuly
Nov.Jan.
. 22
13,23,29,5,
. 10
27,15,21,26,31,
. 19
14,20,2^,9,6,
6,
6, 8,. 16
. 15
6,20,2,
4,21,
, 1968
196919691969
1969, 1969
19691970197019701970
, 1970
197019711971
197119711971
19721972
, 1972
, 1973
1974197^
1974
19741975
Time
0630
00300500063007000330
113008000130183010301630
020022300500003008000600
113002001430
+2200
010001001700
09300330
Dis charge
(ft3/s)
*210
*376313208325212
225271
*408265247250
306235
*403203250262
*290207204
*457
+210202
*434
*277206
Gage height
(ft)
5.00
6.145.724.985.805.02
5.125.446.355.405.285.30
5.675.206.324.945.305.38
5.574.954.93
a/6.68
+5.04.93
a/6.53
5.484.96
Date
Oct.Oct.MayJuneAug.Aug.
Sept
Aug.SeptSept
JuneAug.
Oct.MayJulyJuly
Oct.Dec.JulyJulyAug.
Dec.Feb.MayJuneAug.
9,17,
12,16,6,19,
. 3,
19,. 14. 17
26,17,
1,22,1,4,
18,2,13,27,5,
23,6,18,21,30,
1975197519761976
19761976
1977
1978, 1978, 1978
19791979
1979198019801980
1980198019811981
1981
19811982198219821982
Time
+2300+ 17000700133007301300
1030
+ 1730+0300+ 1230
13000830
2400100001000400
17001800230002301830
07000800
+ 160005000530
Dis charge
(ft3 /s)
222*340295292241266
*195
203*520
242*334
202240373
-374
201277
*674355300
358260232
*445304
Gage height
(ft)
a/5.10a/5.90
5.605.585.245.41
4.86
a/4.94a/7.05
5.255.86
4.935.236.126.13
4.925.487.826.005.63
6.025.37
a/5. 186.605.66
+ About.a/ From floodmark.
99
Table 29. Streamflow records of Qaringeel Stream, Yap--Continued
Water
year
1968-^
1969
1970
1971
1972
1973
1974
1975
B.
Date
Many days (46)
Many days (118)
Many days (63)
April 18, 19
Many days (36)
Many days (135)
Many days (19)
Many days (76)
Annual minimum discharge
Di scharge
(ft 3/s)
0
0
0
.01
0
0
0
0
Water
year
1976
1977
1978
1979
1980
1981
1982
Date
Many days (56)
Many days (118)
Many days (122)
Many days (97)
Many days (58)
Many days (61 )
Many days (52)
Di scharge
(ft 3/s)
0
0
0
0
0
0
0
April to September 1968.
100
Table
29
. S
tream
flow
re
cord
s of
Qarlngeel
Str
eam
, Y
ap
Co
ntin
ue
d
Year
1968
1969
1970
1971
1972
1973
1974
Total
Mean
Max.
Mln.
Total
Mean
Max.
Mln.
Total
Mean
Max.
Mln.
Total
Mean
Max.
Mln.
Total
Mean
Max.
Mln.
Total
Mean
Max.
Min.
Tota
l
Mean
Max.
Mln.
Cale
ndar
ye
ar -- -- --
397.59
1.09
32 0
369.53
1.01
28 0
533.
941.46
18.0
1
357.68 .98
27 0
294.
16 .68
20 0
573-76
1.57
23 0
Jan.
1.37 .044
.50
0 7.46 .24
3.1
0 35.9
4
1.16
11.0
2
22.6
0
.73
7-2 .01
0 0 0 0 44.7
2
1.44
11.13
C.
Feb.
Mar.
0 0
0 0
0 0
0 0
13.8
0 6.70
.49
.22
11
5.9
0 0
29.8
2 36.82
1.07
1.19
6.4
11.04
.02
46.1
9 52.79
1.59
1.70
20
270
.02
0 0
0 0
0 0
0 0
3.25
10
.05
.12
.32
.47
8.0
.01
0
Monthly
and
annu
al discharges,
In
Apr.
Ma
y
0 0.
08
0 .003
0 .0
50
0
.02
11.18
.001
.3
6.0
1 1.
40
0
0 8.86
0 .29
0 1.
80
0
40.12
49.6
6
1.34
1.60
18
13.0
1 .03
2.91
2.
12
.097
.068
1.3
.60
0 0
0 1.55
o .0
500
.41
0 0
42.60
29.82
1.42
.96
18
14.0
1 0
June
2.88 .096
.92
0 36.42
1.21
13.03
16.7
7
.56
6.9 .01
58.45
1.95
9-8 .09
25.96
.87
6.7 .03
30.0
3
1.00
4.7 .11
57.34
1.91
20.0
4
July
28.38
.92
8.8 .03
152.23
4.91
32.12
35.0
9
1.13
8.1 .03
75.1
7
2.42
16.07
27.59
.89
7.4
0 25.9
8.84
3.6 .16
68.60
2.21
23.17
cubic
feet
pe
r second
Aug.
37.8
1
1.22
11.08
57.2
4
1.85
21.05
119.01
3.84
28.05
38.7
8
1.25
11.05
47-58
1.53
10.0
6
9.72 .31
2.1 .01
61.83
1-99
23.0
4
Sept.
54.66
1.82
13.0
5
61.4
9
2.05
13.11
51.43
1.71
11.02
56.66
1.89
12.04
86.7
7
2.89
21.0
3
71.70
2.39
20.0
3
20.8
5
.70
4.5 .07
Oct.
60.23
1.94
14.01
29.48
.95
9.4 .04
58.49
1.89
14.0
5
62.8
02.
0313
.10
11.2
1.3
62.
3 .01
55.98
1.81
9.0 .06
102.35
3.30
12.21
Nov.
2.42 .081
.88
0 31.7
41.
065.
6 .03
29.6
5.99
7.7 .05
30.5
81.
0211
.09
24.6
8.82
7.5 .05
28.0
1 93
9.0 .03
76.71
2.56
19.02
Dec.
14.9
2.48
3.3 .02
16.42
.53
5.0 .01.
22.27
.72
3.6 .04
19.1
4.6
25.
5 .03
7.28 .23
2.5
0 26.19
.84
9.8 .01
55.64
1.79
18.01
Water
year -- --
397.52
1.09
32 0
336.
76 .92
28 0
531.83
1.46
18.01
427.03
1.17
27 0
182.
15 .50
20 0
449.
24
1.23
23 0
Tabl
e 29.
Stre
amfl
ow records
of Qa
ring
eel
Stream,
Yap Continued
O
ro
Year
1975
1976
1977
1978
1979
1980
1981
1982
Tota
l
Mean
Max.
Min.
Tota
l
Mean
Max.
Min.
Tota
l
Mean
Max.
Min.
Tota
l
Mean
Max.
Min.
Tota
l
Mean
Max.
Min.
Total
Mean
Max.
Min.
Tota
l
Mean
Max.
Min.
Tota
l
Mean
Max.
Min.
Cale
ndar
ye
ar
416.
631.
1442 0
340.
27 .93
27 0
339.
18 93
52 0
409.
101.12
40 0
391.81
1.07
26 0
401.
561.
1028 0
468.
561.28
32 0
Jan.
90.66
2.92
42.0
6
4.31 .14
2.0 .01
3-89 .13
.65
0 9.62 .31
5.0
0
.20
.006
.03
0
.40
.013
.10
0 46.44
1.50
15.0
4
24.2
0
.78
14.0
1
C.
Feb.
.16
.006
.04
0 2.68 .092
1.5
0
.04
.001
.01
0 17.1
1
.61
8.3
0 0 0 0 0 3-55 .12
1.1
0 23-14
.83
14.0
1
31.61
1.13
12 0
Mont
hly
and
annual di
scha
rges
, in cu
bic
feet per
second Continued
Mar.
03
.001
.02
0 4.33 .14
2.2
0 0 0 0 0
.02
.001
.01
0 5.55 .18
4.0
0 17.14
.55
9.2
0
.71
.023
.33
0 23.4
3
.76
16 0
Apr.
19.53
.65
15 0 19.21
.64
4.7
0 0 0 0 0 0 0 0 0 0 0 0 0 14.45
.48
11 0 0 0 0 0 0 0 0 0
May
32.1
4
1.04
5.3 .04
44.62
1.44
27.0
2
16.78
.54
6.6
0 0 0 0 0 8.22 .27
5.0
0 35.0
4
1.13
28.01
1.02 .033
.37
0 14.45
.47
4.0
0
June
41.37
1.38
9.7 .04
35.1
1
1.17
7.8
0 15.9
2
.53
11.0
3
30.6
9
1.02
13 0 64.69
2.16
12 0 30.6
0
1.02
7.9 .02
22.5
5
.75
4.6 .01
183.72
6.12
92.01
July
39.54
1.28
9.2 .04
44.5
0
1.44
9.2 .06
90.7
3
2.93
22.03
30.6
1
.99
15.02
63.0
8
2.03
15.0
3
103.81
3.35
24.04
110.25
3.56
25.14
4.58
1.34
11.03
Aug.
59.6
4
1.92
10.0
6
72.6
1
2.34
20.0
3
51-3
9
1.66
7.0 .10
107.
61
3.47
14.0
7
79.1
3
2.55
26.0
8
25.8
1
.83
5.1 .01
62.02
2.00
16 0 49.79
1.61
20.01
Sept.
36.69
1.22
6.0 .05
43.98
1.47
9.9 .01
102.79
3.43
52.0
4
77.46
2.58
40.0
4
28.89
.96
7.0 .01
56.0
1
1.87
16.0
7
80.20
2.67
17.01
46.2
7
1.54
14.01
Oct.
58.26
1.88
15.0
1
4.25 .14
2.5
0 1.97 .064
.56
0 62.6
02.02
13.0
6
58.4
91.89
21.0
1
67.1
22.
1618
.04
51-31
1.66
15.0
1
Nov.
13.0
5.4
46.
00 26.52
.88
12 0 5-75 .19
4.6
0 34.87
1.16
4.0 .05
23.83
.79
9-3
0 4.48 .15
1.7 .01
23.49
.78
7.6 .04
Dec.
25.5
6.8
29.6 .01
38.1
51.
237.
4 .01
49.92
1.61
15.01
38.51
1.24
8.1 .01
59.7
31.
9322
.01
43.15
1-39
13.03
47.4
31.
5332
.03
Wate
r ye
ar
554.
46
1.52
420
368.
22
1.01
27 0
350.
46 .96
52 0
330.
76 .91
40 0
385.74
1.06
26 0
428.
86
1.17
28 0
461.
08
1.26
25 0
537-28
1.47
92 0
Table 30. Streamflow records of Daloelaeb Stream, Yap (16892800)
(Formerly published as Dalolab Stream, Yap)
Location; Lat 9°31'05" N., long 138°06'21" E., on left bank 0.1? mi north of
Daloelaeb Hill water tank and 1.3 mi northwest of Protestant Mission Church
in Colonia.2 Drainage area: 0.07 mi .
Period of record: April 1968 to December 1981 (discontinued).
Gage: Water-stage recorder and concrete control. Altitude of gage is 110 ft
from topographic map).
Remarks; Records good. No diversion above station.
Average discharge; 13 years, 0.366 ft /s (265 acre-ft/yr).
Extremes for period of record: Maximum discharge, 180 ft /s Sept. 15, 1973
(gage height, ^.80 ft, from floodmark in well), f rom rating curve extended
above 17 ft /s; no flow for many days each year.
Discharge measurement made after the end of continuous discharge record
Sept. 15, 1982 0.09 ft 3 /s
103
Table 30. Streamflow records of Daloelaeb Stream, Yap--Continued
A. Annual maximum discharge (*) and peak discharges above base (75 ft /s)
Date
Aug.
JuneJulyJulyJulyAug.
Oct.Aug.Aug.Aug.Sept
Oct.Jan.Apr.Aug.Sept
Jan.Mar.Sept
Sept
July
Oct.Oct.Nov.Dec.Jan.
2,
24,13,23,28,5,
27,8,21,26,
. 19
I**,20,24,6,
6,
9,6,
7,
. 15
2,
12,25,4,5,21,
1968
1969196919691969
1969
1969197019701970
, 1970
197019711971
19711971
197219721972
, 1973
1974
19741974
197419741975
Time
1300
18000100053002000700
110020001400
+ 1030+ 1630
0200+2300060008000700
2400+ 11302400
2200
1600
22001430070014300300
Dis- Gage charge height
(ft 3 /s) (ft)
*106
8883
*1197898
7591
*14392135
*111891078691
97
*106
*180
*76
7583
*1109691
3.97
3.713.644.143.563.86
3.513.764.423.774.33
4.043.733.983.683.76
3.84
3.97
£/4.80
a/3.54
3.523.644.023.833.76
Date
Oct.Oct.MayAug.Aug.
Sept
Dec.JuneAug.Aug.SeptSept
JuneAug.
Oct.Oct.MayJulyJuly
Oct.Dec.JulyJulyAug.
9,17,
12,6,19,
. 3,
12,21,3,19,
. 14
. 17
26,17,
1,30,
22,1,4,
18,2,13,27,5,
19751975
197619761976
1977
19771978
19781978
, 1978, 1978
19791979
19791979
198019801980
1980198019811981
1981
Time
22301600
+07000800
+ 1300
1145
023019001300173003001230
1300+0900
22301600093001000430
18001700
+230002001800
Dis charge
(ft3 /s)
96*116
91105110
*68
76949076
*152146
110*116
*1287989114116
87109
*151125108
Gage height
(ft)
3.834.103.763.964.02
3.40
3.543.803.753.534.524.45
4.024.10
4.243.553.704.064.08
3.704.014.514.214.00
+ About.a/ From floodmark.
104
Table 30. Streamflow records of Daloelaeb Stream, Yap--Continued
Water
year
1968*/
1969
1970
1971
1972
1973
1974
B.
Date
Many days (94)
Many days (197)
Many days (136)
Many days (23)
Many days (73)
Many days (190)
Many days (74)
Annual minimum discharge
Discharge
(ft 3 /s)
0
0
0
0
0
0
0
Water
year
1975
1976
1977
1978
1979
1980
1981
Date
Many days (108)
Many days (116)
Many days (163)
Many days (220)
Many days (147)
Many days (143)
Many days (135)
Di scharge
(ft 3 /s)
0
0
0
0
0
0
0
- April to September 1968.
105
Table
30.
Stre
amfl
ow records
of Da
loel
aeb
Stream,
Yap Continued
C.
Monthly
and
annual
Year
1968
1969
1970
1971
1972
1973
1974
Tota
l
Mean
Max.
Min.
Tota
l
Mean
Max.
Min.
Tota
l
Mean
Max.
Min.
Tota
l
Mean
Max.
Min.
Tota
l
Mean
Max.
Min.
Tota
l
Mean
Max.
Min.
Tota
l
Mean
Max.
Min.
Cale
ndar
year
131.84 .36
11 0
133.17 .36
13 0
181.80 .50
6.1
0
116.25 .32
10 0 94.5
5.26
16 0
182.
12 .50
9.0
0
Jan.
0.27 .009
.10
0 2.98 .096
1.5
0 11.1
9
-36
3.5
0 6.34 .20
,2.
*0 0 0 0 0 13.3
5
.^3
3.5
0
Feb. 0 0 0 0 3.70 .13
2.9
0 8.28 .30
2.0
0 16.1
0
.56
7.0
0 0 0 0 0
.22
.008
.06
0
Mar.
0 0 0 0 1.72 .056
1.7
0 14.6
5
.47
4.1
0 17.4
1
.56
10.0
2
0 0 0 0 4.34 .14
3-5
0
Apr.
0 0 0 0 0 0 0 0 0 0 0 0 12.5
7
.42
5.0
0 1.00 .033
.40
0 0 0 0 0 12.5
3
.42
6.4
0
May
0 0 0 0 2.14 .069
.62
0 2.56 .083
.75
0 19.6
0
.63
3-5
0 .22
.007
.06
0 0.05 .002
.02
0 9.75 .31
5.5
0
disc
harg
es,
in
June
0.05 .002
.04
0 11.0
5
.37
3.4
0 5.26 .18
2.7
0 23.17
.77
3.7 .01
9.28 .31
2.0
0 5.96 .20
1.1
0 20.0
4
-67
8.0
0
July
8.61 .28
2.1
0
48.29
1.56
11.0
1
11.6
4
.38
3.2
0 29.15
.94
6.1 .01
9.61 .31
2.5
0 7.31 .24
1.5
0 23.47
.76
9.0 .02
cubic
feet per
seco
nd
Aug.
14.81
.48
5.0
0 20.7
7
.67
7.0
0 50.95
1.64
13.0
1
10.8
4
.35
3.2 .01
14.2
3
.46
3.2
0 7.16 .23
1.9
0 14.9
6
.48
7.5
0
Sept.
14.1
7
.47
3-3 .01
21.8
9
.73
4.6 .01
22.1
2
.74
5.0
0 18.44
.61
3.9
0 28.5
3
.95
5.2
0 32.3
7
1.08
16.01
5.67 .19
1.5 .01
Oct.
21.2
8.69
5.3
0 8.50 .27
2.8
0 17.4
2.5
65.
10 19.6
0.6
34.
0 .01
2.45 .079
.90
0 20.2
4.6
53-9 .01
33.67
1.09
3.9 .01
Nov.
0.53 .018
.35
0 13.69
.46
3-0 .01
8.32 .28
2.8
0 9.90 .33
4.0 .01
7.88 .26
2.0 .01
11.59
.39
4.9 .01
28.0
7.9
45.
3 .01
Dec.
2.82 .091
.88
0 5.24 .17
2.0
0 6.50 .21
1.2
0 4.41 .14
1.3
0 3.20 .10
1.2
0 9-87 .32
4.0
0 16.0
5.5
24.
40
Wate
r year __ ~
129.04 .35
11 0
128.36 .35
13 0
180.
13 .49
6.1
0
136.
63 .37
10 0 66.38
.18
16 0
146.03 .40
9.0
0
Table
30.
Streamflow records
of Daloelaeb
Stream,
Yap Continued
O -J
Year
1975
1976
1977
1978
1979
1980
1981
Tota
l
Mean
Max.
Min.
Tota
l
Mean
Max.
Min.
Total
Mean
Max.
Min.
Total
Mean
Max.
Min.
Tota
l
Mean
Max.
Min.
Tota
l
Mean
Max.
Min.
Tota
l
Mean
Max.
Min.
Calendar
year
140.58 .39
15 0
121.72 .33
8.0
0
102.98 .28
15 0
151.44 .41
12 0
127-90 35
9.0
0
128.
41
.35
8.7
0
152.
28 .42
10 0
Jan.
30.94
1.00
15 0 1.69 .055
.72
0 1.19 .038
.A3
0 3.53 .11
2.7
0 0 0 0 0
.02
.001
.01
0 12.6
1
.41
3-9 .01
C.
Feb.
0.03 .001
.01
0
.89
.031
.60
0 0 0 0 0 A. 15
.15
2.0
0 0 0 0 0
.62
.021
.18
0 9.74 .35
6. 4
0
Monthly
and
annual discharges,
Mar.
0 0 0 0 1.03 .033
.65
0 0 0 0 0 0 0 0 0 1.86 .06
1.7
0 6.12 .20
3. A
0
.14
.004
.09
0
Apr.
5.39 .18
4.6
0 6.91 .23
1.8
0 0 0 0 0 0 0 0 0 0 0 0 0 2.94 .098
2.7
0 0 0 0 0
May
5.88 .19
1.2
0 13.5
7
.44
8.0
0 3.17 .10
1.2
0 0 0 0 0 2.24 .07
1.5
0 10.33
.33
8.1
0
.08
.002
.06
0
June
15.62
.52
4.0
0 13.5
4
.45
3-0 .01
4.15 .14
2.9
0 10.3
2
.34
5.5
0 18.7
0
.62
4.0
0 11.01
.37
2.4 .01
7.12 .24
2.3
0
in cubic
July
12.3
7
.40
3.2
0 13.63
.44
3.0 .01
26.9
3
.87
6.7
0 13.9
3
.45
4.9
0 20.9
1
.67
5.0
0 37.11
1.20
8.7 .01
31.t
)3
1.00
8.8 .01
feet pe
r se
cond
Continued
Aug.
24.2
3
.78
4.4 .01
26.88
.87
7.0 .01
23-7
7
.77
3-9 .02
34.5
8
1.12
5.1
0 25.6
3
.83
9.0 .03
12.0
4
.39
3.8 .01
22.0
5
.71
5.9
0
Sept.
12.80
.43
3.3
0 19.38
.65
4.3
0 27.4
4
.91
15 0 26.23
.87
12 0 8.53 .28
2.4
0 13.77
.46
2.5 .01
26.7
7
.89
6.1
0
Oct.
20.29
.65
5.5
0 1.17 .038
.50
0 13-93
.45
4.9
0 35.2
41.14
9.7 .01
21.1
3.6
85.9
0 18.44
59
4.7
0 18.32
59
4.8 .01
Nov.
3.74 .12
1.5
0 8.84 .29
4.0
0 34.58
1.12
5.1
0 13.0
5.4
42.
0 .01
7.10 .24
3.2
0 1.11 .04
.40
0 7.57 .25
2.5 .02
Dec.
9.29 .30
4.4
0 14.19
.46
1.8 .01
26.23
.87
12 0 10.43
.34
2.1
0 21.80
.70
6.6
0 14.90
.48
6.0
0 16.8
5.54
10.0
1
Wate
r ye
ar
185.05 .51
15 0
130.84 .36
8.0
0
110.85 .30
15 0
109.07 .30
12 0
136.59 .37
9.7
0
143.99 .39
8.7
0
143.99 .39
8.8
0
Table 31. Streamflow records of Peemgoy Stream, Yap (16892900)
(Formerly published as Pemgoy Stream, Yap)
Location; Lat 9 O31'07" N., long 138°06'36" E., on right bank at Taalgum,
100 ft upstream from confluence with Taalgum Stream, 0.3 mi southeast of
Mount Peemgoy, and 1.0 mi northwest of Protestant Mission Church in Colonia,2 Drainage area: 0.14 mi .
Period of record: April 1968 to July 1982 (discontinued).
Gage: Water-stage recorder. Concrete control since Mar. 30, 197^' Altitude of
gage is 60 ft (from topographic map).
Remarks; Records fair. No diversion above station.
Average discharge: 13 years (water years 1969-81), 0.591 ftvs (428 acre-ft/yr)
Extremes for period of record; Maximum discharge, 335 ft /s July 13, 1981
(gage height, 5^0 ft), from rating curve extended above 15 ft /s; no flow
for many days most years.
Discharge measurements, in cubic feet per second, made outside the
period of continuous discharge record
Sept. 23, 1965 0.45
Oct. 9, 1967 .10
Aug. 4, 1982 .01
Sept. 15, 1982 .68
108
Table 31. Streamflow records of Peemgoy Stream, Yap Continued
A. Annual maximum discharge (*) and
Date
Aug.
JulyAug.
Aug.
Aug.Aug.Aug.Sept
Oct.Jan.Sept
Oct.Mar.JuneSept
Sept
Nov.JuneJuneJuly
Nov.Jan.
Oct.Oct.MayAug.Aug.Sept
2,
23,5,
8,
15,21,26,
. 19
14,20,
. 6,
3,6,25,
. 8,
. 15
17,6,20,2,
4,21,
9,17,
12,6,19,
. 4,
1968
19691969
1970
197019701970
, 1970
197019711971
1971197219721972
, 1973
197319741974
1974
19741975
19751975
1976197619761976
Time
1300
05000630
1930
0630+ 130018001630
020022300600
+0030110001300030
2200
1900003001001700
+08000300
23001730
+0700+070013000500
Dis- Gage charge height
(ft 3 /s) (ft)
*66
*161104
79
7619874
*207
8671
*90
11215176
*173
*240
818388
*156
+*150102
7482
+ 100106
*11075
2.94
4.063.45
3.13
3.08a/4. 39
3.054.47
3.223.023.23
3.543.963.09
a/4. 17
4.72
2.863.183.254.01
-_3.42
3.063.17
3.473.523.07
peak discharges above base (70 ft /s)
Date
Sept
JuneAug.SeptSept
JuneAug.
Oct.Oct.MayJulyJuly
Dec.JulyJulyAug.
Oct.Dec.Feb.Mar.June
3,
21,3,
. 14
. 17
26,17,
1,30,
22,1,4,
2,13,27,5,
31,23,6,22,21,
1977
19781978, 1978, 1978
19791979
19791979
198019801980
198019811981
1981
19811981
198219821982
Time
+ 1100
1900130002301230
12300900
230015000830
+0100+0400
1730230003001800
02000700080022300600
Dis- Gage charge height
(ft 3 /s) (ft)
*87
7572
*314192
86*165
*2349088
+ 150179
96*33522894
7111712886
*303
£/3.24
3.073.03
a/5.26£/4.34
3.224.10
4.683.283.25
4.22
3.335.404.633.33
3.023.60
a/3.723.225.18
+ Abouta/ From floodmark.
109
Table 31. Streamflow records of Peemgoy Stream, Yap Continued
B. Annual minimum discharge
Water
year
1968-7
1969
1970
1971
1972
1973
1974
1975
Di scharge
Date (ft 3 /s)
Many days (87)
Many days (107)
Many days (68)
Many days
Many days (86)
Many months ( 165)
Many days (16)
Many days (34)
0
0
0
.01
0
0
0
0
Water
year
1976
1977
1978
1979
1980
19811982^X
Di scharge
Date (ft 3 /s)
Many days (15)
Many days (63)
Several days (8)
Feb. 16, Mar. 30
Feb. 2
Many days (59)
Many days
0
0
0
0
0
0
.01
a/ April to September 1968.
b/- October 1981 to July 1982.
110
Tabl
e 31.
Stre
amfl
ow records
of Peemgoy
Stream,
Yap
Cont
inue
d
C.
Monthly
and
annual di
scha
rges
, in
Year
1968
1969
1970
1971
1972
1973
1974
1975
Total
Mean
Max.
Min.
Tota
l
Mean
Max.
Min.
Tota
l
Mean
Max.
Min.
Tota
l
Mean
Max.
Min.
Tota
l
Mean
Max.
Min.
Tota
l
Mean
Max.
Min.
Tota
l
Mean
Max.
Min.
Tota
l
Mean
Max.
Min.
Cal endar
year --
198.*4*4 .54
17 0
185.
70 .51
15 0
2*47
.21
.68
7.8 .01
16*4
.99
.45
13 0
159.48 .4*4
11 0
328. *»
5 90
13 0
22*4.62
.62
20 0
Jan.
1-93 .062
.50
0 6.70 .22
2.5
0 16.2
2
.52
4.7 .01
9.31 .30
3.9 .01
0 0 0 0 30.6
2
99
8.7 .03
46.57
1.50
20.0*4
Feb. .05
.002
.01
0 7-31 .26
5-9
0 10.9
4
.39
2.7 .01
27.6
8
.95
13 0 0 0 0 0 1.01 .036
.2*4
0 1.*»0
.050
.07
.02
Mar. 0 0 0 0 3-14 .10
2.8
0 19.0
9
.62
6.3 .01
23.1
0
75
12.0*4
0 0 0 0 5.71 .18
3.5
0 0.33 .011
.05
0
Apr. 0 0 0 0 0 0 0 0 0 0 0 0 12.1
8
.41
*4.6 .01
1.*»
1
.0*»7
.53
0 0 0 0 0 28.52
95
13 0 7.25 .2*4
6.2
0
May
0.02 .001
.02
0 3.46 .11
.89
0 7.28 .23
2.3
0 21.7
7
.70
*4.2 .01
.50
.016
.15
0 0 0 0 0 15.44
.50
7.5 .01
9.47 .31
2.0
0
June
0.33 .011
.16
0 13.50
.45
3.3 .01
8.*»6
.28
*».2
0 29.97
1.00
6.5 .02
10.6
8
.36
3.6 .02
9.6*
4
32
2.0
0 36.9
0
1.23
11.05
23-7
9
.79
6.0 .02
July
8.85 .28
2.4
0 75-2
6
2.*»3
17.05
17.4
9
.56
4.8 .01
37.4
6
1.21
7.8 .0*4
17.56
.57
5-9
0 12.93
.42
3-0
0 38.83
1.25
10.0
8
16.9
1
.55
3.3 .0*4
cubi
c feet per
Aug.
14.3
3
.*»6
5-5
0 31.68
1.02
10.0*4
56.0
6
1.81
15.02
15.1
3
.49
4.2 .03
16.9
7
.55
*4.1 .03
10.9
2
.35
*».4
0 23.12
.75
10.0
*4
37.9
8
1.23
6.0 .05
Sept
.
20.3
3
.68
*».6
0 34.6
8
1.16
6.0 .07
34.02
1.13
8.8 .02
27.7
7
93
5.8 .03
32.9
7
1.10
9.5 .03
*41.
85
1.40
11.0
2
9-69 .32
2.0 .04
26.10
.87
*4.0 .0*4
seco
nd
Oct.
26.82
.87
7.0 .01
11.6
9.3
83.0 .03
2*4.
80 .80
7.3 .03
35-9
41.16
7.0 .06
8.*»
3.2
72.9 .03
40.85
1.32
7.0 .02
64.39
2.08
7.0 .08
31.3
81.01
6.*» .0*4
Nov. .79
.026
.30
0 18.9
1.6
3*».
o .02
9-96 .33
3.0 .01
12.7
6.4
35.
4 .0*4
12.85
.43
4.3 .0*4
2*4.24 .81
9-6 .02
47-9
21.
6010
.0*4
9.36 .31
3-7 .02
Dec.
*».2
8.1
41.
00 7.
28 .23
3-0 .01
10.*»7 .34
2.0 .02
7.98 .26
1.*» .0*4
3.53 .11
1.0
0 19-0
5.6
17.
3 .01
26.30
.85
6.7 .03
1*4.08 .45
4.7 .03
Wate
r ye
ar __
192.45 .53
17 0
178.
35 .49
15 0
235.76 .65
7.8 .01
196.
86 .54
13 0
100.15 .27
11 0
273.
98 .75
13 0
308.
*41
.85
20 0
Tabl
e 31-
Stre
amfl
ow records
of Pe
emgo
y Stream,
Yap Continued
Year
1976
1977
1978
1979
1980
1981
1982
Total
Mean
Max.
Min.
Tota
l
Mean
Max.
Min.
Tota
l
Mean
Max.
Min.
Tota
l
Mean
Max.
Min.
Tota
l
Mean
Max.
Min.
Tota
l
Mean
Max.
Min.
Tota
l
Mean
Max.
Min.
Cale
ndar
ye
ar
223-
32 .61
18 0
185.04 .51
35 0
255.
08 .70
220
219.
42 .60
15 0
199.94 .55
14 0
254.85 .70
12 0 __
Jan.
2.83 .091
1.1 .01
3-31 .11
.80
.01
7.12 .23
3.6 .01
.43
.014
.03
.01
.37
.012
.02
.01
21.9
9
.71
5.2 .02
9.33 .30
7-0 .01
C.
Feb.
1.66 .057
.71
.01
.26
.009
.01
0 8.52 .30
3.2 .01
.28
.010
.01
0 1.06 .037
.29
0 18.0
5
.64
9.5 .01
20.32
.73
6.5 .01
Monthly
Mar.
2.02 .065
.85
0
.08
.003
.01
0
.36
.012
.03
0 3.34 .11
2.3
0 8.36 .27
3.4 .01
50
.016
.24
0 15.6
2
.50
8.0 .01
and
annual discharges,
in cu
bic
feet pe
r se
cond
Con
tinu
ed
Apr.
10.54
.35
2.7
0 0 0 0 0
.31
.010
.04
0
.34
.011
.02
.01
3.86 .13
3.1 .01
.05
.002
.01
0
52
.017
.07
.01
May
31.08
1.00
18.0
1
3.38 .11
1.1
0 1.98 .064
1.0
0 6.02 .19
3.0 .01
16.6
6
.54
13.01
.46
.015
.30
0 13.4
0
.43
5.0 .01
June
28.2
4
.94
5.5 .03
7.17 .24
4.3 .01
15.6
6
.52
5.4 .01
33-6
7
1.12
6.0 .01
16.63
.55
3.5 .01
12.11
.40
2.7
0
105.00
3.50
51.0
3
July
29.86
96
6.1 .07
45.5
4
1.47
7.4 .01
21.2
2
.68
5.5 .01
35.49
1.15
8.7 .02
58.56
1.89
14.0
3
52.37
1.69
12.0
3
27.16
.88
7.3 .02
Aug.
40.87
1.32
10.06
37.0
8
1.20
5.0 .05
54.91
1.77
7.1 .05
48.15
1.55
15.04
18.4
9
.60
4.9 .02
38.7
8
1.25
9.0 .01
Sept
.
33.6
9
1.12
5.7 .04
66.39
2.21
35.0
2
44.03
1.47
22.03
13.55
.45
3.4 .01
22.70
.76
5.6 .03
44.84
1.49
9.8 .01
Oct.
2.31 .075
.69
.01
.74
.024
.15
.01
59.00
1.90
15.0
3
38.71
1.25
9.9 .01
28.7
9.9
36.
6 .01
32.1
31.04
6.4 .02
Nov.
14.6
3.4
95.
7 .01
2.80 .093
1.7 .01
23.5
1.7
83-
0 .04
12.1
5.40
4.5 .01
2.55 .085
.68
.01
11.34
.38
3.1 .01
Dec.
25-59
.83
4.3 .01
18.29
.59
6.8 .01
18.46
.60
3.8 .02
27.29
.88
11.0
1
21.9
1.7
17.
5 .01
22.2
3.7
211
.01
Water
year
235.61 .64
18 0
205.
74 .56
35 0
175-94 .48
22 0
242.
24 .66
15 0
224.84 .61
14 0
242.
40 .66
12 0 __
Table 32. Streamflow records of Taalgum Stream, Yap (16893000)
(Formerly published as Talagu Stream, Yap)
Location; Lat 9°31'09" N., long 138°06'32" E., on left bank at Taalgum,
300 ft upstream from confluence with Pemgoy Stream, and 1.2 mi northwest
of Protestant Mission Church in Colonia.2 Drainage area: 0.08 mi .
Period of record; April 1968 to April 1979 (discontinued).
Gage; Water-stage recorder. Concrete control since Apr. 3? 1975- Altitude of
gage is 100 ft (from topographic map).
Remarks; Records fair. No diversion above station. 3 Average discharge; 10 years (water years 1969-78), 0.341 ft /s (247 acre-ft/yr),
Extremes for period of record; Maximum discharge, 330 ft /s Sept. 14, 1978
(gage height, 3.98 ft), from rating curve extended above 9.0 ft /s; no flow
for many days each year.
A. Discharge measurements, in cubic feet per second, made outside the period of continuous discharge record
Date Discharge
9-20-65 0.05
9-23-65 .19
10- 9-67 .08
6-13-79 .23
6-29-79 .72
7-11-79 1.4
7 ^ /* "7 f\ /" O -26-79 .63
8_ 8-79 - .14
8-21-79 .06
q_ c;_7Q ________ _ ___ 0.1 fii.7 J 1 J C/.UI
Date
9-19-79 -
10- 5-79 -
10-30-79
11- 9-79
12- 4-79
1 9 9ft "7Q
1 O "2 Qfii-o-ou -------
2 1 Q n- 1-OU -------
9-17-80
9 1 c Q o-15-02 - -'
Di scharge
_ e/0.01
______ .03
_ e/ .01
_ e/ .01
_ £/ .01
______ .03
nu______ .56
_ .25
e/ Estimated,
113
Table 32. Streamflow records of Taalgum Stream, Yap--ContInued
B. Annual
Date
Aug.
JulyJulyAug.
Feb.Aug.Aug.Aug.Aug.Sept
Oct.Jan.Apr.JulySept
Mar.Sept
Sept
Apr.JuneJuneJuly
2,
13,23,5,
23,5,15,21,26,
. 19
1*,20,24,8,
. 6,
6,. 8,
. 15
20,6,20,2,
1968
19691969
1969
19701970197019701970
, 1970
197019711971
19711971
19721972
, 1973
197419741974
1974
maximum
Time
1300
010005000700
+070020000630130018001700
023023000500
+24000930
11000200
2300
1200013001301730
discharge (*) and peak
Dis charge
Gage height
(ft 3 /s) (ft)
*66
55-137
85
855365
*14563138
72576357
*8l
115*117
*213
636863
*141
2.36
2.183.222.62
a/2.632.152.343.302.313.23
2.442.222.32
a/2.212.57
2.98^/3.00
3.98
2.312.382.323.26
di scharges
Date
Oct.Oct.Nov.Jan.Aug.
Oct.Oct.MayAug.Aug.Sept
Sept
Nov.Dec.JuneAug.SeptSept
JulyAug.
12,25,*,21,26,
9,17,
12,6,19,
A,
3,
27,12,21,3,
. 14
. 17
3,17,
19741974
197419751975
19751975
1976197619761976
1977
197719771978
1978, 1978, 1978
19791979
above base (50
T ime
22301500080004001330
230017300700070013000500
1000
080002001930130003001230
+ 1900+0900
Dis charge
ft 3 /s)
Gage hei ght
(ft 3 /s) (ft)
5455
*1148263
85*128127108113+55
-79
56546561
-330255
61*164
2.172.182.972.582.36
2.572.912.90
a/2.76^/2.80
--
2.52
a/2.282.262.382.333.983.65
a/2.33a/3.14
+ About.a/ From floodmark.
114
Table 32. Streamflow records of Taalgum Stream, Yap Continued
Water
year
19681'
1969
1970
1971
1972
1973
C.
Date
Many days (111)
Many days (183)
Many days (178)
April 7, 8
Many days (74)
Many days (177)
Annual minimum discharge
Di scharge
(ft 3/s)
0
0
0
0
0
0
Water
year
1974
1975
1976
1977
1978
1979^
Date
Many days (42)
Many days (78)
Many days (58)
Many days (91)
Many days (137)
Many days (106)
Di scharge
(ft 3 /s)
0
0
0
0
0
0
a/- April to September 1968.
b/- October 1978 to April 1979.
115
Tabl
e 32.
Streamflow records
of Ta
algu
m Stream,
Yap Continued
D.
Monthly
and
annual
Year
1968
1969
1970
1971
1972
1973
1974
Tota
l
Mean
Max.
Min.
Tota
l
Mean
Max.
Min.
Tota
l
Mean
Max.
Min.
Tota
l
Mean
Max.
Min.
Tota
l
Mean
Max.
Min.
Tota
l
Mean
Max.
Min.
Tota
l
Mean
Max.
Min.
Cal en
dar
year
136.
48 .37
12 0
124.
18 .34
12 0
179-
79 .49
5-7 .01
95.7
7.2
69.
60 76.60
.21
6.5
0
171.
09 .47
7.6
0
Jan.
1.37 .044
.48
0 4.43 .14
2.4
0 10.13
.33
2.6 .01
5.04 .16
2.0
0 0 0 0 0 11.30
.36
2.9 .01
Feb.
0 0 0 0 3.46 .12
3.0
0 7.87 .28
2.2 .01
14.71
.51
6.9
0 0 0 0 0
.29
.010
.08
0
Mar.
0 0 0 0 1.7 .055
1.7
0 16.96
.55
4.3 .01
15.75
.51
9.6 .02
0 0 0 0 5.32 .17
4.1
0
Apr. 0 0 0 0 0 0 0 0 0 0 0 0 13.5
4.4
54.0 .01
.80
.027
30
0 0 0 0 0 13.19
.44
7.0
0
May
0.01 .000
3.01
0 3.84 .12
1.0
0 2.25 .073
1.3
0 20.8
2
.67
3-3 .01
.23
.007
.08
0 0 0 0 0 7.50 .24
4.1
0
discharges,
in cu
bic
feet
per
second
June 0 0 0 0 8.55 .28
2.0
0 5.^5 .18
3-5
0 22.05
.7^
5.2 .03
8.31 .28
2.7
0 4.63 .15
.9*»
0 19.20
.64
7.2 .02
July
8.23 .26
2.2
0
48.0
8
1.55
12 0 11.37
.37
3.3
0 27.95
.90
5.7 .03
10.3
9
.34
2.8
0 7.08 .23
1.7
0 21.3
3
.69
7.6 .03
Aug.
15.9
6
.52
4.7
0 21.13
.68
7.0
0 38.69
1.25
12 0 12.23
.39
3.3 .02
10.8
2
.35
2.4
0 5.89 .19
2.3 .01
13.10
.42
6.6 .01
Sept.
15.95
.53
3. A
0 21.7
2
.72
3.9 .01
22.8
9
.76
5.4
0 21.1
6
.71
4.7 .03
19.4
7
.65
5.2 .02
21.8
4
73
6.5
0 4.09 .14
1.0 .01
Oct.
24.41
.79
4.7
0 8.57 .28
2.5
0 16.20
.52
5.3 .01
18.19
.59
3.5 .03
2.34 .076
.73
.01
18.03
.58
3.2 .01
31.3
61.
013.
6 .03
Nov.
0.54 .018
.29
0 17.0
3.5
73-1
0 7.84 .26
2.1 .01
6.93 .23
3.5 .01
6.21 .21
1.9 .02
10.77
.36
5.0 .01
27.9
1.93
7.0
0
Dec.
6.11 .20
2.1
0 6.19 .20
2.5
0 9.90 .32
2.4 .01
1.96 .063
.40
.01
1.70 .055
.54
0 8.36 .27
3.6 .01
16.50
.53
A. 3
0
Wate
r year «
135.
75 .37
12 0
122.
03 .33
12 0
186.65 .51
5.7 .01
112.
60 .31
9.6
0 ^9.69
.14
6.5
0
132.
48 .36
7.6
0
Table
32.
Streamflow records
of Ta
algu
m Stream,
Yap
Cont
inue
d
Year
1975
1976
1977
1978
1979
Total
Mean
Max.
Mln.
Total
Mean
Max.
Mln.
Tota
l
Mean
Max.
Mln.
Tota
l
Mean
Max.
Mln.
Tota
l
Mean
Max.
Mln.
Cale
ndar
ye
ar
133.35 .37 14 0
115.12 .31
8.0 0
95.71
.26 16 0
132.79 .36 16 0 __
Jan.
31.2
9
1.01
14.0
1
1.73 .056
.47
.01
1.64 .053
.40
.01
3-70 .12
2.2
0 .06
.002
.01
0
D
Feb.
0.13 .005
.04
0
.85
.029
.40
0
.18
.006
.01
0 4.15 .15
2.0
0 0 0 0 0
Monthly
and
annual di
scha
rges
, In cubic
feet pe
r se
cond
Con
tinu
ed
Mar.
0.02 .001
.01
0 .65
.021
.40
0 0 0 0 0 0 0 0 0 1.68 .054
1.4
0
Apr.
3.80 .13
3.3
0 5.80 .19
1.5
0 0 0 0 0 0 0 0 0 0 0 0 0
May
5.17 .17
.84
.01
14.1
1
.46
8.0
0 1.44 .046
.48
0 .26
.008
.07
0
June
13.70
.46
2.4 .02
15.2
3
.51
2-9 .02
3.46 .12
2.2
0 9.37 .31
4.6
0
July
10.4
5
.34
2.0 .02
14.2
4
.46
3.2 .04
29.94
.97
5-9 .02
10.2
8
33
3.1 .01
Aug.
21.0
4
.68
3.5 .03
24.20
.78
7-3 .05
17.4
3
.56
2.5 .02
28.10
91
3-7 .01
Sept.
13-94
.46
2.5 .02
17.82
.59
3.7 .02
27.0
6
.90
16.01
31.41
1.05
16.0
1
Oct.
20.66
.67
5.3 .02
1.21 .039
.32
.01
1.04 .034
.17
.01
25.64
.83
7.0 .02
Nov.
3-89 .13
1.6
0 7.34 .24
3.2 .02
2.15 .072
1.2
0 11.10
.37
1.5 .02
Dec.
9.26 .30
3.3 .03
11.94
.39
2.1 .02
11.37
.37
4.0
0 8.78 .28
2.0 .01
Water
year
175.31 .48
14 0
f28.
44 .35
8.0
0
101.
64 .28
16 0
101.
83 .28
16 0 __
Table 33. Streamflow records for Burong Stream, Yap, (16893100)
Location: Lat 9°32'05" N., long 138°07'19" E., on left bank at Dugor,
0.25 mi upstream from mouth, and 0.5 mi northeast of Mount Gamuw.2 Drainage area: 0.23 mi .
Period of record; April 1968 to September 1982.
Gage: Water-stage recorder and concrete control. Altitude of gage is
15 ft (from topographic map).
Remarks; Records good. No diversion above station.
Average discharge; 14 years, 0.973 ft'/s (705 acre-ft/yr).
Extremes for period of record; Maximum discharge, 550 ft /s June 21, 1982
(gage height, 5.^5 ft), from rating curve extended above 15 ft /s;
no flow for many days most years.
118
Table 33. Streamflow records of Burong Stream, Yap--Continued
A. Annual maximum discharge (*) and
Date
Sept
Oct.JulyAug.
Aug.Aug.Aug.Sept
Oct.Oct.JulySeptSeptSeptSept
Mar.SeptSept
Sept
Apr.Aug.
Oct.Oct.Nov.Jan.
. 22
13,23,5,
15,21,26,
. 19
3,1*,22,
6,. 15. 22. 26
6, 5,. 8,
. 15
20,12,
10,25,**,21,
, 1968
19681969
1969
197019701970
, 1970
1970197019711971
, 1971, 1971, 1971
197219721972
, 1973
19741974
19741974
19741975
Time
0700
130005000700
0700013018301630
1130020003000800140001301100
103012300130
2300
12001800
0030160009000330
Dis charge
(ft 3 s)
* 58
91*220133
17312091
*250
1029198136
*26190102
236287
*338
*442
*368122
154263
*285191
Gage height
(ft)
2.96
3.324.183.66
3.923.563.324.33
3.423.323.383.684.383.313.42
4.264.504.71
5.09
4.833.58
3.804.394.494.02
peak discharges above base (75 ft /s)
Date
Oct.MayAug.
Sept
JuneSeptSept
Aug.
Oct.Dec.JulyJuly
JulyJulyAug.
Dec.Feb.Mar.JuneAug.
17,12,19,
. 3,
21,. 14. 17
17,
1,24,1,4,
13,27,5,
23,6,22,21,30,
197519761976
1977
1978, 1978, 1978
1979
19791979
19801980
19811981
1981
19811982198219821982
Time
173007001300
1130
190003001230
0900
2200013001000330
2300+0200+ 1800
07000730220006000500
Dis- Gage charge height
(ft 3 /s) (ft)
*201152194
*240
154*445201
*232
256110150
*505
*433194157
151211112
*550128
4.083.794.04
4.28
a/3.805.104.08
4.24
4.363.483.775.30
5.06a/4.04ai/3.82
3.784.163.505.453.62
+ About.a/ From floodmarks.
119
Table 33- Streamflow records of Burong Stream, Yap Continued
Water
year
1968-7
1969
1970
1971
1972
1973
1974
1975
B.
Date
Many days (100)
Many days (179)
Many days (91)
February 1
Many days (44)
Many days (172)
Many days (22)
Many days (84)
Annual minimum discharge
Di scharge
(ft 3 /s)
0
0
0
.01
0
0
0
0
Water
year
1976
1977
1978
1979
1980
1981
1982
Date
Many days (65)
Many days (131)
Many days (126)
Many days (132)
Many days (83)
Many days (94)
Many days (32)
Di scharge
(ft3 /s)
0
0
0
0
0
0
0
a/ April to September 1968.
120
Table
33
Streamflow records
of Bu
rong
Stream,
Yap
Cont
inue
d
C.
Monthly
and
annu
al
Year
1968
1969
1970
1971
1972
1973
1974
1975
Tota
l
Mean
Max.
Min.
Tota
l
Mean
Max.
Min.
Tota
l
Mean
Max.
Min.
Tota
l
Mean
Max.
Min.
Tota
l
Mean
Max.
Min.
Tota
l
Mean
Max.
Min.
Tota
l
Mean
Max.
Min.
Tota
l
Mean
Max.
Min.
Calendar
year
302. A3
.83
25 0
330.44 .91
20 0
457.67
1.25
15.01
303.
01 .83
22 0
232.
74 .64
20 0
504.50
1.38
20 0
336.96 .92
33 0
Jan.
.45
.015
.13
0 9.05 .29
3.0
0 27.4
9
.89
6.1 .02
17.6
5
.57
6.1 .01
0 0 0 0 49.8
9
1.61
11.19
76.39
2.46
33.0
4
Feb.
0 0 0 0 14.95
.53
7. A
0 19.7
2
.70
A.I .01
35.5
8
1.23
19 0 0 0 0 0 2.64 .094
.82
.01
0.40
,.014
.10
0
Mar.
0 0 0 0 3.26 .11
2.9
0 34.94
1.13
10.0
3
40.19
1.30
21.0
3
0 0 0 0 9.59 .31
7.5
0 0 0 0 0
Apr.
0 0 0 0 0 0 0 0 0 0 0 0 21. A3 .71
A. 7 .03
2.36 .079
.88
0 0 0 0 0 Al.30
1.38
20.0
1
11. A3 .38
10 0
May
0.05 .002
.05
0 7.29 .2A
2.0
0 8.04 .26
2.6
0 28.2
7
.91
5.6 .02
.67
.022
.10
0 0 0 0 0 25.8
7
.83
12 0 6.96 .22
2.1
0
disc
harg
es,
in cubic
feet pe
r second
June
0.08 .003
.08
0 20.0
3
.67
3.7
0 1A.5
A
.A8
7.0
0 56.08
1.87
10.0
5
16. OA .53
A. 5 .02
7.67 .26
1.A
0 55.6
7
1.86
17.07
31.11
1.0A
7-5
0
July
13. 2A .A3
3.2
0
109.
A7
3.53
25.O
A
38.03
1.23
8.8
0 76. A3
2.A7
15.1
0
^8.8
1
.93
9.3
0 2A.29
.78
3.3
0 55. A9
1.79
10.08
30.5
5
.99
8.0 .01
Aug.
32.2
7
1.04
7. A
0 49.72
1.60
17.0
6
92.2
0
2.97
20.O
A
38.5
7
1.2A
8.2 .04
38. A2
1.2A
11.03
12.3
6
.AO
2.7
0 39. 6A
1.28
17.0
3
53.7
7
1.73
12.0
3
Sept
.
A4.54
1.48
7.3
0 48.62
1.52
9.7 .12
59.9
9
2.00
14.0
1
71.1
7
2.37
12.0
3
87.8
9
2.93
22.05
72.2
3
2.41
20.0
1
19.32
.64
5.0 .08
37.8
0
1.26
7.7 .01
Oct.
53.0
51.
7111 0 14
.76
.48
4.9 .03
45-67
1.47
11.0
4
54.8
41.77
10.1
2
13.70
.44
4.7 .02
64.77
2.09
8.7 .07
99.90
3.22
11.1
5
54.4
01.75
13.04
Nov.
1.00 .033
.46
0 40.82
1.36
7.5 .01
25.1
9.8
45.8 .03
21.5
9.7
27.7 .10
18.09
.60
6.2 .03
32.1
81.07
8.5 .04
70.8
62.
3617
.05
13.63
.45
6.5
0
Dec.
11.20
.36
3.3
0 14.27
.46
5.0 .01
19.5
2.6
33.9 .03
7.14 .23
1.8 .03
3.61 .12
1.0
0 19.2
4.62
8.5 .02
34.33
1.11
6.8 .02
20.52
.66
7.4 .05
Wate
r year __
297.83 .82
25 0
309.
91 .85
20 0
464.
48
1.27
15.0
1
351.
18 .96
22 0
151.
95 .42
20 0
415.
60
1.14
20 0
453.50
1.24
33 0
Tabl
e 33-
Stre
amfl
ow records
of Burong Stream,
Yap Continued
fo N:
Year
1976
1977
1978
1979
1980
1981
1982
Tota
l
Mean
Max.
Min.
Total
Mean
Max.
Min.
Tota
l
Mean
Max.
Min.
Tota
l
Mean
Max.
Min.
Total
Mean
Max.
Min.
Tota
l
Mean
Max.
Min.
Total
Mean
Max.
Min.
Calendar
year
293.01 .80
21 0
267.
67 .73
39 0
349.32 .96
31 0
355.09 .97
22 0
335-44 .92
25 0
409.73
1.12
20 0
Jan.
2.92 .094
.82
0 3.23 .10
.88
0 8.76 .28
3.6
0
.16
.005
.02
0
.49
.016
.08
0 30.5
2
.98
A. 8 .04
14.9
9
.48
12.0
1
C.
Feb.
1.79 .062
.74
0
.05
.002
.02
0 13.87
.50
6.2
0 0 0 0 0
.95
.033
.22
0 32.6
8
1.17
17.01
27.7
8
.99
13 0
Mont
hly
and
annual di
scha
rges
, in cubic
feet per
seco
nd Continued
Mar.
1.60 .052
.90
0 0 0 0 0 0 0 0 0 3.00 .097
2.2
0 17.6
2
.57
10 0 .57
.018
.24
0 22.6
8
.73
13 0
Apr.
13.9
5
.47
5.0
0 0 0 0 0 0 0 0 0 0 0 0 0 12.9
2
.43
11 0 0 0 0 0
.18
.006
.01
0
May
39.0
2
1.26
21.02
1.85 .060
1.0
0
.46
.015
.42
0 3-12 .10
2.3
0 28.36
.91
18 0
.05
.002
11 0 11.45
.37
4.7
0
June
39.3
0
1.31
10 0 8.72 .29
4.8
0 28.45
95
8.3
0 51.0
8
1.70
10 0 26.6
5
.89
7.6 .01
15.9
4
.53
20.0
1
218.
35
7.28
115 0
July
36.1
0
1.16
10.0
1
83.3
9
2.69
20.0
1
28.82
.93
5.3
0 62.38
2.01
16.0
1
94.2
4
3.04
25.10
83.35
2.69
20.0
1
43.5
4
1.40
14.0
3
Aug.
57.4
6
1.85
15.06
43.78
1.41
6.7 .03
79.4
8
2.56
9.0 .06
71.50
2.31
20.07
25.69
.83
9.3 .03
60.34
1.95
15 0 49.00
1.58
13.02
Sept.
59.2
2
1.97
12.05
71.75
2.39
39.0
6
64.4
1
2.15
31.0
1
28.64
.96
7.5
0 41.35
1.38
7.6 .09
75.18
2.51
16.0
1
36.79
1.23
11.0
2
Oct.
1.03 .033
.25
0 1.74 .056
.13
0 80.22
2.59
19.0
6
57.30
1.85
22 0 49-15
1-59
10.0
6
39.4
61.27
7.4 .04
Nov.
12.0
7.4
06.
80 11.11
.37
2.1 .02
22.35
.74
3.8 .06
14.4
1.4
84.
1 .01
4.14 .14
1.0 .03
33.3
71.
114.0 .10
Dec.
28.55
92
6.6
0 42.0
51.
3613 0 22.5
0.7
26.
9 .02
63-50
2.05
22.0
1
33.88
1.09
12.0
2
38.27
1.23
12.0
1
Wate
r ye
ar
339.
91 .93
21 0
254.
42 .70
39 0
279.15 .76
31 0
3'44.95
.94
20 0
383.
48
1.05
25 0
385.
80
1.06
20 0
535.
86
1.47
115 0
Table 3^« Streamflow records of Mukong Stream, Gagil-Tamil (16893200)
Location: Lat 9°32'05" N., long 138°10 I 18" E., on right bank 0.2 mi upstream
from mouth and 0.9 mi south of U.S. Coast Guard LORAN station.2 Drainage area: 0.50 mi .
Period of record: Occasional low-flow measurements, water years 1972-75*
Continuous record December 197^ to June 1978, October 1978 to September
1982 (July to September 1978, stage-discharge relation indefinite due
to blocked control).
Gage: Water-stage recorder. Altitude of gage is 5 ft (from topographic
map).
Remarks; Records fair. Since 1978, small amount of water is pumped at times
from site about 500 ft upstream for domestic use in nearby village.
Average discharge; 6 years (water years, 1976-77, 1979-82), 2.08 ftVs (1,510
acre-ft/yr).3 Extremes for period of continuous record: Maximum discharge, 153 ft /s June
21, 1982 (gage height, 4.10 ft), from rating curve extended above 18
ft^/s; minimum discharge, 0.07 ftvs Apr. 9, 1979, Mar. 15, 1980,
May 4, 1981.
123
Table 34. Streamflow records of Mukong Stream, Gagil-Tamil Continued
A. Discharge measurements, in cubic feet per second, made outside the periods of continuous discharge record
Date
12- 4-71
1-14-72
2-24-72
3-23-72
4-21-72
5-18-72
6-16-72
7-15-72
8-10-72
10-12-72
10-16-72
12-19-72
1- 9-73
Discharge
0.55
93
6.9
3.3
1.7
.28
1.2
1.2
3.6
1.1
1.2
1.1
.28
Date
1-29-73
2-16-73
2-26-73
5- 7-73
6-20-73
7- 2-73
8-15-73
8-29-73
12- 4-73
1-16-74
2- 4-74
2-14-74
3- 7-74
Discharge
0.21
.06
.12
.18
.35
3-7
79
1.2
1.1
2.8
1.2
1.5
.34
Date
4-19-74
5- 7-74
5-17-74
6- 5-74
7-10-74
8-16-74
9-12-74
10- 3-74
7-21-78
8-30-78
9-14-78
9-29-78
Discharge
1.3
.65
1.4
8.7
3.0
2.2
.98
3.1
.86
2.4
6.1
1.6
124
Table 34. Streamflow records of Mukong Stream, Gagil-Tamil Continued
B. Annual maximum discharge (*) and peak discharges
above base (25 ft 3/s, 1974-79; 50 ft 3/s, 1980-82)
Date
Dec. 5,Jan. 22,Apr. 30,
Oct. 10,May 12,June 17,June 25,Aug. 19,Sept. 13Sept. 18
Dec. 21,Aug. 20,Aug. 28,Sept. 3,
Dec. 12,Sept. 14Sept. 17
197419751975
19751976197619761976
, 1976, 1976
1976197719771977
1977, 1978, 1978
Time
060010000130
0200103021300600160013301000
093010301830
+ 1100
070005001500
Dis charge
(ft 3 /s)
26*3735
35292531
*402932
243933
*52
35*7141
Gage height
(ft)
222
2222222
2223
232
.29
.69
.63
.63
.42
.23
.48
.78
.40
.53
.20
.75
.56
.08
.62
.40
.83
Date
Oct.Dec.
Dec.Mar.MayJulyJuly
July
Nov.Dec.Jan.Feb.JuneJulyAug.
5,14,
24,20,
22,1,4,
14,
27,23,24,6,21,15,16,
19781978
19791980
198019801980
1981
198119811982
1982198219821982
Time
15300700
05002400100004300630
0200
0700100007301000070009301100
Dis charge
(ft 3 /s)
*4135
62696373
*110
*90
757085102
*1536367
Gage height
(ft)
2.812.62
3.273-373.283. A33.80
3.62
3.453.383.573.734.103.283.34
+ About.
C. Annual minimum discharge
Water
year
1975-7
19761977
1978
Date
Several days inApril
March 15-17 -Part of each day,
April 3-9 - Several days inApr i 1 , May -
Discharge
(ft 3 /s)
0.111 "y
.11
nq vj
Water
year
1 Q7QiJ/J 1980
1981
1982
Date
April 9 March 15 Mav k --------i la y T
March 5, 6
Discharge
(ft 3 /s)
0.07.07.07 .20
- December 1974 to September 1975.
125
Tabl
e 34.
Streamflow records
of Mukong Stream,
Gagi1-Tamil Continued
D.
Monthly
and
annual di
scha
rges
, in
Year
1974
1975
1976
1977
1978
1979
Tota
l
Mean
Max.
Min.
Tota
l
Mean
Max.
Min.
Tota
l
Mean
Max.
Min.
Tota
l
Mean
Max.
Min.
Tota
l
Mean
Max.
Min.
Tota
l
Mean
Max.
Min.
Calendar
year --
725.
361.99
27.11
772.
872.
1119
.15
713.
031.95
30.1
3
531.26
1.46
12.09
Jan.
126.08
i».0
727
.73
32.3
8
1.04
3.2 .56
32.9
2
1.06
3.5 .50
44.31
1.43
9.0 .40
16.03
.52
.77
.40
Feb.
19.1
0
.68
1.2 .33
18.8
7
.65
1.9 .25
13.7
1
.49
1.2 .30
i»6.30
1.65
8.3 .32
8.38 .30
.60
.15
Mar.
10.07
.32
.80
.20
14.97
.48
2.5 .15
6.86 .22
.35
.15
9.14 .29
.55
.15
15-90
.51
2.4 .15
Apr.
29.33
.98
17.1
1
i»9.06
1.64
9.0 .30
4.72 .16
.23
.13
5.55 .19
.60
.09
7.74 .26
.96
.11
May
44.2
8
1.43
5.5 .58
90.2
0
2.91
19.6
1
26.2
5
.85
3.5 .15
9.42 .30
3.4 -09
9.78 .32
1.7 .09
June
75.6
3
2.52
6.1 .63
94.5
6
3.15
15.7
5
67.8
8
2.26
9.2 .77
35.74
1.19
5.6 .13
58.17
1.94
7.4 .13
July
73.32
2.37
11.6
0
85.1 2.75
13 1.0
148.
5
4.79
13 1.5
87.3
3
2.82
10.67
cubi
c feet per
seco
nd
Aug.
83-33
2.69
8.2 .89
101.5
3.27
14 1.3
126.
9
4.09
12 1.2
__
103.
1
3.33
11 1.6
Sept
.
53.9
5
1.80
5.7 .49
139.
6
4.65
17 1.0
109.03
3.63
30.8
3
__ 65.49
2.18
6.0 .99
Oct.
102.
43.
3014 1.
1
26.^
6.85
1.8 .45
57.25
1.85
5.1 .45
166.
865.
3817
.83
53-45
1.72
11.3
5
Nov.
47.4
71.58
7.7 .52
33.12
1.10
8.0 .36
i»1.
201.37
3.0 .50
56.2
21.
875.
6 .65
38.1
01.
274.
7 .47
Dec.
99.2 3.20
10 1.3
60.4
01.95
8.4 .88
87.0
52.81
12.8
3
77.8
12.
5113
.55
60.67
1.96
11.77
67.79
2.19
12.3
9
Water
year __ --
836.
51
2.29
19.1
5
683.
40
1.87
30.1
3
__
655.
67
1.80
17.0
9
Tabl
e 34.
Stre
amfl
ow re
cord
s of Mukong St
ream
, Ga
gi1-
Tami
l--C
onti
nued
Year
1980
1981
1982
Total
Mean
Max.
Min.
Tota
l
Mean
Max.
Min.
Tota
l
Mean
Max.
Min.
Cale
ndar
year
610.38
1.67
18.1
8
735.
232.
0125
.10
Jan.
18.44
.59
.93
.35
95.14
3.07
20.7
5
55-82
1.80
31.42
D
Feb.
14.54
.50
1.6 .22
65.66
2.34
25.4
7
89-03
3.18
30.3
4
Mont
hly
and
annual di
scha
rges
,
Mar.
33.58
1.08
8.1 .18
14.25
.46
1.8 .22
50.41
1.63
20.2
4
Apr.
32.2
5
1.08
8.4 .39
5.35 .18
.35
.10
14.56
.49
2.4 .26
May
31-1
5
1.00
11.2
0
6.30 .20
.66
.10
41.66
1.34
8.9 .29
June
59-83
1.99
6.9 .47
26.76
.89
5-9 .10
244.15
8.14
79 31
in cu
bic
July
107.
9
3.48
18 1.2
93-39
3.01
14.9
3
130.
61
4.21
25.7
1
feet per
Aug.
66.3 2.14
5.0
1.0
92.3 2.98
13 1.0
139.
09
4.49
21.34
second Cont
i nue
d
Sept.
78.7 2.62
9.4
1.1
83-4
7
2.78
16.4
7
123.
10
4.10
18 1.5
Oct.
69-9
42.
266.
8 .59
105.0
3-39
12 1.3
Nov.
20.68
.69
2.5 .43
85.20
2.84
18 1.1
Dec.
77.0
72.49
15.63
62.4
12.01
20.6
2
Wate
rye
ar
602.03
1.64
18.18
650.31
1.78
25.10
1,141.04
3.13
79.2
4
Table 35« Streamflow records of GMaew Spring, GagM-TamM (16893300)
(Formerly published as Bileiy Spring, Gagil-Tomil)
Location; Lat 9°32'l6" N., long 1380 11'17" E., on right bank at Binaew,
200 ft downstream from main spring and 0.5 mile southwest of Gagi1 Elementary
School.
Period of record: Continuous-record station April 1968 to September 1974
(discontinued). Low-flow partial-record station 1975-82.
Gage; Water-stage recorder until September 1974. Altitude is 60 ft (from
topographic map).
Average discharge; 6 years, 0.129 ft^/s (93.4 acre-ft/yr).
Remarks; Records fair. No diversion above station.
Extremes for period of continuous record; Maximum daily discharge, 1.5 ft /s
Sept. 8, 1972; no flow for many days in 1968-69, 1973.
A. Discharge measurements, in cubic feet per second, made after the end of continuous discharge record
Date
10- 3-7^
11- 9-74
4- 2-75
4-30-75
7- 8-75
8-27-75
10- 7-75
12- 3-75
!_ 8-76
4- 1-76
Discharge
0.05
.45
£/.01
.10
.18
.16
.10
.04
.08
.05
Date
5-19-76
8- 9-76
10-10-76
12- 2-76
1-20-77
11-29-77
12-29-77
2- 1-78
3-15-78
4-12-78
Di scharge
0.42
.09
.07
.20
.07
.01
.03
.03
.02
.01
Date
7-21-78
8-30-78
10-26-78
11-28-78
12-28-78
12-27-79
9-16-80
10-20-80
7-18-81
5_6-82
Di scharge
0.03
.02
.02
.02
0
.18
.40
.21
.11
.02
e/ Estimated.
128
Table
35
. S
tream
flow
re
cord
s of
GM
aew
S
pring,
Gag
! 1-
Tam
l I C
ontinued
B.
Monthly
and
annu
al di
scha
rges
, in
Year
1968
1969
1970
1971
1972
1973
1974
Cale
ndar
ye
ar
Jan.
Tota
l
Mean
Ma
x.
Mln.
Total
Mean
Max.
Mln.
Tota
l
Mean
Max.
Min.
Total
Mean
Max.
Min.
Tota
l
Mean
Max.
Min.
Tota
l
Mean
Max.
Mln.
Total
Mean
Max.
Mln.
A 1.
09 .11
1.4
0 39.5
6.11
.87
.01
61.9
7.17
1.3 .02
56.63
.15
1.5 .02
24.8
7.068
.96
0 --
.05
.002
.01
0 3.71 .12
.22
.06
2.38 .077
.11
.05
2.90 .094
20.0
3
.63
.020
.03
.01
8.20 .26
72
.09
Feb.
0 0 0 0 1.27 .045
.09
.02
2.35 .084
.12
.05
3.09 .11
.70
.03
.10
.004
.01
0 1.89 .068
.17
.01
Mar.
0 0 0 0
.56
.018
.04
.01
3.24 .10
.18
.06
10.80
.35
.80
.19
0 0 0 0 1.11 .036
.19
.01
Apr.
1.69 .056
.10
.02
0 0 0 0
.30
.010
.01
.01
2.03 .068
.08
.04
2.85 .095
.19
.06
0 0 0 0 2.16 .072
.27
.01
May
1.07 .035
.25
0
.16
.005
.03
0
.45
.015
.03
.01
4.00 13
1.0 .05
1-33 .043
.07
.03
0 0 0 0 4.17 .13
.57
.02
June
0 0 0 0
.62
.021
.05
.01
.55
.018
.09
.01
7.87 .26
1.3 .08
.97
.032
.06
.02
0 0 0 0 9.52 .32
1.0 .16
July
0.37 .012
.06
0 8.21 .26
1.0 .01
2.35 .076
.12
.06
12. 48 .40
1.2 .15
2.43 .078
.17
.0<i
.01
.0003
.01
0 6.75 .22
.50
.10
cubic
feet
pe
r
Aug.
2.1(
6
.079
.15
.03
11.7
3
.38
1.4 .11
7.72 .25
.87
.07
3.92 .13
.24
.05
5.97 .19
51
.08
0 0 0 0 8.99 .29
1.1 .09
Sept.
6.19 .21
.46
.11
5.92 .20
.36
.09
7-52 .25
.51
.13
6.96 .23
1.0 .05
19-25
.64
1.5 .07
5.15 .17
.68
0 1.73 .058
.08
.04
second Oct.
9.85
.3
2 96
.08
4.40 .14
.22
.10
7.69 .25
.64
.12
12.2
9.4
0.8
4.1
8
4.01 .13
.22
.08
10.63
.34
.96
.08
Nov.
2.18
.073
.17
.02
5.79 .19
.38
.13
4.31 .14
.27
.11
3-29 .11
.20
.04
1.87 .062
.08
.04
5.25 .18
.42
.09
Dec.
1.33
.0
43
.13
.01
4.21 .14
.18
.09
3.13 .10
.14
.05
1.16 .037
.05
.02
1.16 .037
.06
.03
3.10 .10
.30
.05
Wate
r ye
ar
40.0
5
.11
1.4
0 41.0
9
.11
.87
.01
60.36
.17
1.3 .04
66.33
.18
1.5 .02
12.93
.035
.68
0 63.50
.17
1.1 .01
Table 36. Streamflow records of Eyeb Stream, GagM-Tamil (16893400)
Location; Lat 9°33'11" N., long 138°09'l4" E., 0.6 mi southeast of Tagireeng
Canal bridge and 1.1 mi northwest of U.S. Coast Guard LORAN station.
Drainage area: 0.22 mi .
Per iod of record; Occasional low-flow measurements water years 1980-81.
Continuous record January to September 1982.
Gage; Water-stage recorder and concrete control. Altitude of gage is 15
ft (from topographic map).
Remarks; Records good. No diversion above station.
Extremes for period of record; Maximum discharge, 490 ft /s June 21,
1982 (gage height, 6.22 ft), from rating curve extended above 14 ft /s
on basis of estimate of peak flow; minimum discharge, 0.12 ft /s May 8,
9, 14, 15, 1982.
A. Discharge measurements, in cubic feet per second, made outside the period of continuous discharge record
Date Discharge Date Discharge
9 _1Q_Qn _______
10-20-80
3 ""> /i Q 1-z4-ol -------
4. 7-81 ....
4-27-81
c_iii_«i _______
----- 1.9
- 4.6
.20
__ 19
______ .04
______ n?
7 1 Q Q i-lo-ol ---------
1 n 1 Q Q')
11 1 r> Q o
1 1 i li Q ">1-zH-oz --------
12-9-82 -
19_9ft_8-5 ________
- 2.2
- - .97
.77rQ - .50
----- - 2.4
._ ____ Hi
130
Table 36. Streamflow records of Eyeb Stream, Gagi1-Tami1 Continued
B. Monthly discharge, in cubic feet per second
Year Jan. Feb. Mar. Apr. May
1982 Total
MeanMax.Min.
49.71
1.6026
.41
79.90
2.8523
.69
37.11
1.208.3.36
11.44
.381.2.19
21.79
.704.4.15
Year June July Aug. Sept.
1982 Total
MeanMax.Min.
291.17
9.71130
.27
122.77
3.9627
.97
95.70
3.0920
.51
80.37
2.6815
.83
Peak discharges above base (150 ft /s): Feb. 6 (0830)
207 ft 3 /s (4.66 ft); June 21 (0430) 490 ft 3 /s (6.22 ft);
Aug. 16 (0900) 153 ft 3 /s (4.14 ft).
131
Low-flow partial-record stations
Table 37 Discharge measurements, in cubic feet per second,
of Faraq Swamp outlets, Yap (16892450)
Location; Lat 9°29'08" N., long 138°04'24" E., and lat 9°29'15" N ->
138°04'21" E., 0.9 mi northwest of Lamear and 4.1 mi southwest of Colonia,
at altitude 5 ft (from topographic map).2 Dra inage area: 0.29 mi .
Period of record: 1968-73-
Date Di scharge Date Di scharge Date Di scharge
10- 9-67
9-25-68
9-20-69
10-16-69
6- 4-70
7-30-70
9- 1-70
10- 5-70
10-30-70
0.25
.58
.48
.26
.07
.30
4.4
.49
.14
11-25-70
12-.18-70
11-12-70
1- 5-71
7- 1-71
7- 7-71
7-20-71
7-27-71
8- 4-71
0.22
.25
.12
.03
.09
.20
.24
.08
.04
10-20-71
2-24-72
3-23-72
4-20-72
7-16-72
8-10-72
9-20-72
10-12-72
0.08
.76
.12
.04
.04
.16
.30
.06
132
Table 38. Discharge measurements, in cubic feet per second,
of Galngun Swamp outlet, Yap (16892460)
Location; Lat 9°29'04" N., long 138O04'40" E., 0.5 mi northwest of Lamear
and 3-9 mi southwest of Colonia, at altitude 30 ft (from topographic
map).2 Drainage area; 0.16 mi
Period of record; 1968-73.
Date
10- 9-67
9-25-68
10-15-68
9-20-69
7-14.70
7-30-70
9- 1-70
9-18-70
10- 5-70
10-29-70
Discharge
0.23
.50
1.2
.40
.15
.24
2.8
.15
.23
.40
Date
11-13-70
11-25-70
12-22-70
1- 5-71
1-28-71
6-30-71
7- 7-71
7-20-71
7-27-71
8- 4-71
Di scharge
0.25
.34
.23
.14
.30
.05
.35
.42
.31
.17
Date
10-20-71
1-13-72
2-24-72
3-23-72
4-20-72
5-18-72
7-15-72
8-10-72
9-19-72
10-12-72
Di scharge
0.16
.26
.25
.29
.17
.16
.20
.21
.50
.23
133
Table 39. Discharge measurements, in cubic feet per second,
of Tamaney Stream, Yap (16892500)
Location; Lat 9°29'49" N., long 138005'52" E., at abandoned German dam,
0.2 mi upstream from mouth and 1.1 mi southwest of U.S. Weather Bureau
Station at airport, at altitude 30 ft (from topographic map).2 Drainage area; 0.17 mi .
Period of record; 1968-82.
Date
8-22-68
9- 4-68
10-17-68
9-19-69
9-30-69
10-14-69
11- 6-69
11-20-69
3-11-70
3-24-70
4- 7-70
4-29-70
5-12-70
7-14-70
7-30-70
9- 2-70
9-22-70
10- 6-70
10-29-70
11-13-70
11-25-70
Di scharge
0.97 .53
3.2
.45
.38
.15
.24
.06 0
0
0
0
.39
.07
.39
3.8
.38
.10
.07
.14
.38
Date
12-22-70
1- 5-71
1-27-71
6-30-71
7- 7-71
7-20-71
7-27-71
8- 4-71
9-17-71
10-20-71
1-13-72
2-24-72
3-23-72
4-20-72
7-15-72
8-10-72
9-20-72
10-12-72
2-19-74
3-11-74
4-21-74
Di scharge
0.04
.13
.04
1.1
.07
.06
.03
.06
.07
.74
.06
11
.04
.08
.06
.08
.09
.02
.18
.20
1.9
Date
5-24-74
6-14-74
7-14-74
9-13-74
4- 4-75
5- 2-75
6-20-75
7-15-75
8-29-75
10- 9-75
12- 5-75
1- 9-76
2-18-76
4- 2-76
5-21-76
7- 6-76
8-11-76
10-10-76
12- 3-76
1-21-77
11-30-77
Di scharge
1.6
.25
.26
.27 0
.25
1.6
.52
.23
.14
.12
.04
e/.01
.32
.15
.09
.74 0
.23
.26
.07
Date
12-30-77
2- 1-78
3-16-78
6-29-78
7-25-78
8-31-78
10-30-78
11-30-78
12-28-78
6-29-79
8-21-79
12-27-79
2- 1-80
9-17-80
10-20-80
7-17-81
5- 5-82
6-17-82
Di scharge
0
.05
0
.09 0
.07
.10
.10 0
.81
.05
.16 0
1.4
1.1
.46
.05
.52
e/ Estimated.
134
Table 40. Discharge measurements, in cubic feet per second,
of Ripu Stream, Yap (16892600)
Location; Lat 9°30'10" N., long 138°06'24" E., 300 ft upstream from mouth
and 0.3 mi southwest of Gitaem water-treatment plant at altitude 10
ft (from topographic map).2 Drainage area: 0.29 mi
Period of record: 1968-82.
Date
3- 7-68
7-29-68
8- 8-68
9- 4-68
9-17-68
10-17-68
12- 6-68
6-14-69
6-28-69
9-19-69
9-29-69
10-16-69
11- 4-69
11-20-69
3-11-70
3-24-70
4- 7-70
4-29-70
5-26-70
7-14-70
7-31-70
9- 2-70
Di scharge
0.63
3.5
.88
.61
.07
3-3
.25
.50
.15
.43
3.8
.19
.15
.07 0
0
0
0
0
.10
.05
3.3
Date
9-22-70
10- 7-70
10-30-70
11-13-70
11-27-70
12-22-70
1- 5-71
1-26-71
6-30-71
7- 6-71
7-20-71
7-27-71
8- 3-71
9-17-71
10-20-71
12- 3-71
1-13-72
3-23-72
4-20-72
5-18-72
7-15-72
8-10-72
Di scharge
0.21
.16
.06
.16
.62
.09
.06
.12
.09
.10
.07
.13
.08
.40
.57
.04
.11
.34
.09
.004
.08
.22
Date
9-20-72
10-12-72
7-16-73
2-17-74
3-11-74
4-21-74
5-23-74
6-14-74
7-14-74
9-13-74
4- 4-75
5- 2-75
6-20-75
7-15-75
8-29-75
10- 9-75
12- 5-75
1- 9-76
2-18-76
4- 2-76
5-21-76
7- 2-76
Di scharge
0.16
.04
.10
.39
.20
1.8
1.7
.19
.20
.21
0
.22
1.6
.85
.33
.17
.93
.07
e/.01
.84
.12
.09
Date
8-11-76
10-10-76
12- 3-76
1-21-77
11-30-77
12-30-77
2- 1-78
3-16-78
6-29-78
7-25-78
8-31-78
10-30-78
11-30-78
12-28-78
6-29-79
8-21-79
12-27-79
9-17-80
10-21-80
7-17-81
5- 5-82
6-17-82
Di scharge
0.86 0
.43
.16
.08
0
.01
0
.09
.01
.13
.11
.11
0
1.2
.14
.09
1.5
.62
.43
.03
.73
e/ Estimated.
135
Table 41. Discharge measurements, in cubic feet per second,
of Dinaey Stream, Yap (16892650)
Location; Lat 9°30'32" N., long 138O06'15" E., at upper Gitaem Reservoir,
0.4 mi northwest of water-treatment plant and 1.5 mi southwest of Colonia,
at altitude 75 ft (from topographic map).2 Drainage area: 0.04 mi .
Period of record; 1980-82.
Date Discharge
9-18-80 0.14
10-21-80 .19
3-25-81 0
4- 8-81 0
7-17-81 .06
5- 5-82 .01 (estimated)
6-17-82 .08
136
Table 42. Discharge measurements, in cubic feet per second,
of Tholomar Stream, Yap (16892700)
Location; Lat 9°30'34" N., long 138°06'21" E., 5 ft upstream from confluence
with Dinaey Stream and 1.4 mi southwest of Colonia, at altitude 70 ft
(from topographic map). Site covered by water from new Gitaem dam since
1975. Reestablished in 1980 as station 16892680 at site 800 ft upstream,
at lat 9°30'37" N., long 138°06'18" E., drainage area 0.10 mi 2 , and
altitude 75 ft (from topographic map).2 Drainage area: 0.13 mi .
Period of record: 1965, 1968-74, 1980-82.
Date
9-23-65
3-23-68
8- 8-68
9- 4-68
10-17-68
6-14-69
6-27-69
9-19-69
9-30-69
10-14-69
11- 4-69
3-24-70
4- 8-70
Di scharge
0.29
.04
1.0
1.2
5.6
.36
.12
.52
.64
.32 .25 0
0
Date
4-29-70
7-14-70
7-30-70
9- 2-70
9-23-70
10- 6-70
10-29-70
11-13-70
11-27-70
12-22-70
1- 6-71
1-27-71
7- 1-71
Di scharge
0
.08
.74
3.8
.26
.28
.11
.22
.70
.16
.18
.10
1.0
Date
7- 6-71
7-20-71
7-21-71
8- 3-71
10-21-71
1-13-72
4-20-72
5-18-72
7-15-72
8-11-72
9-20-72
10-13-72
1-11-73
Di scharge
0.15
.10
.15
.40
.27
.11
.09
.01
.06
.21
.14
.03
.02
Date
2-17-74
3-11-74
4-21-74
9-18-80
10-21-80
3-25-81
4- 8-81
7-23-81
5- 5-82
6-17-82
Di scharge
0.27
.23 2.6
.43
.32 0
0
.07 I/. 01
.22
Estimated.
137
Table 43. Discharge measurements, in cubic feet per second,
of Mabuuq Stream, Yap (16893050)
Location; Lat 9°3Tl4" N., long 138°07'00" E., at Mabuuq, 0.4 mi upstream
from mouth and 0.9 mi northwest of Ganiir bridge in Colonia, at altitude
45 ft (from topographic map).2 Drainage area: 0.30 mi .
Period of record: 1968-72.
Date
9-26-68
10-16-68
6-14-69
9-18-69
10- 8-69
11- 4-69
11-20-69
1-21-70
3-11-70
4- 8-70
4-29-70
Di scharge
0.14
27
.20
.14
.14
.37
.11
.42
0
0
0
Date
5-26-70
7-14-70
7-30-70
9- 2-70
9-24-70
10- 7-70
10-29-70
11-13-70
11-27-70
12-22-70
1- 6-71
Di scharge
0
.03
.08
7.2
1.6
.12
.36
.16
.60
.18
.07
Date
7- 1-71
7- 6-71
7-19-71 ---
8- 3-71
10-21-71
1-14-72
3-25-72
4-21-72
6-16-72
8-11-72
9-20-72
Di scharge
0.59
.20
.22
.58
.11
.08
.17
.01
.51
.16
.13
138
Table 44. Discharge measurements, in cubic feet per second,
of Monguch Stream, Gagil-Tamil (16893180)
Location; Lat 9 031'59" N., long 138 O09'57" E., 0.7 mi northeast of Tamilang
Elementary School and 1.0 mi south of Coast Guard LORAN station, at
altitude 20 ft (from topographic map).2 Drainage area: 0.18 mi
Period of record:
Date
5- 3-79 ----- --
5- 7-79
5-11-79
5-15-79 -----
5-29-79 - - -
5-30-79 -----
6- 4-79
7-25-79 - -
9-16-80
1979-82.
Di scharge
a/0.02
a/. 03
/ /\ *"» .02
/ *> r~_ .35
a/. 30
/ oO_ .08 £/.06
a/. 05
- 1.3
Date
10-20-80 -
3 1 1< Q 1-Z^-Ol -------
4. 7-81 .
4 O"7 Q 1-Z/-OI -------
5-14-81 -
7 11 Q 1
5 C. Q 1-D-OZ --------
9 1 C. Q O
Di scharge
2 n
. .16
nQ------- .(JO
1 O
I f
~
17------- w 1 o
a/ Measurements from Lyon Associates, 1980, made by V-notch weir and reported
in gallons per minute.
bj Measurements made near mouth at lat 9 O32'03" N., long 138°10'09" E.,
altitude 5 ft:5-6-82 0.24 ft 3 /s
6-15-82 .48 ft 3/s
139
Table 45. Discharge measurements, in cubic feet per second,
of Gi laew Stream,
Location: Lat 9°32'12" N., long 138°
downstream from Gilaew Spring, 0
south of Gagi 1
Drainage area: 0.1
Period of
Date
3-20-68 -
8-19-68 -
10- 4-68 -
10-23-68 -
10-31-68 -
11-19-68 -
12- 3-68 -
1- 7-69 -
2-10-69 -
6-13-69 -
9-19-69 -
9-29-69 -
11- 6-69 -
11-18-69 -
1-14-70 -
1-29-70 -
8-31-70 -
9-15-70 -
9-29-70 -
10- 5-70 -
10-30-70 -
record:
Elementary School
5 mi .
1968-80.
11 '29
.4 mi
, at
Discharge Date Discharge
0.12
.27
.10
- .25
.24
.16
- .31
.10 0
e/.02
- .36
- .46
.88
.32
.24
.20
1.2
- .15
.19
- .35
- .38
11-12-70 0.11-25-70
12-28-70
1- 6-71
6-30-71 1.
7- 8-71 .
7-19-71 .
7-27-71
8- 3-71 .
10-19-71
1-14-72
2-24-72
3-23-72 .
4-21-72
5-18-72 .
6-16-72
7-15-72 .
8-10-72
9-18-72 2.
10-12-72
1- 9-73 .
45
54
14
15
1
27
33
73
30
17
24
17
42
10
06
08
13
48
0
39
04
Gagil-Tamil (16893310)
" E., at
upstream
al t i tude
Date
7-11-43
3- 7-74
4-19-74
5- 7-74
5-17-74
6- 5-74
7-10-74
8-16-74
9-12-74
10- 3-74
11- 9-74
12- 3-74
1- 2-75
2-13-75
4- 2-75
4-30-75
5-20-75
7- 8-75
8-27-75
10- 7-75
12- 3-75
road culvert
from mouth,
15 ft (from
Di scharge
e/0.02
.13
.16
.16
.24
.78
.46
1.2 .27
.32
1.4
.69
.40
.36
.06
.29
.19
.80
.36
.64
.20
, 0.3 mi le
and 0.45 mi
topographic
Date
!_ 8-76
2-18-76
4- 1-76
5-19-76
7- 7-76
8- 9-76
10-10-76
12- 2-76
1-20-77
11-29-77
12-29-77
2- 1-78
3-15-78
4-12-78
6-28-78
7-21-78
8-30-78
10-26-78
11-28-78
12-27-78
12-27-79
map) .
Di scharge
0.19
.10
.11
1.7
.42
.71
.41
.26
.10
.13
.13
.07
.06
.02
.05
.13
.11
.06
.14
.30
.18
e/ Estimated.
140
Table 46. Discharge measurements, in cubic feet per second,
of Yanbilang Stream, Gagil-Tamil (16893350)
Location: Lat 9°32'45" N., long 138°H'48" E., 250 ft upstream from mouth
and 0.3 mi northeast of Gagi1 School, at altitude 5 ft (from topographic
map).2 Drainage area: 0.03 mi .
Period of record: 1968-72.
Date
10-10-67
10-14-68
11-19-68
12- 3-68
1- 7-69
2-10-69
4-18-69
6-13-69
10-15-69
11- 6-69
Di scharge
0.04
1.6
0
.51
0
0
0
e/.01
.02
.12
Date
3-23-70
4- 6-70
.4-21-70
5-11-70
8-31-70
9-29-70
10- 7-70
10-30-70
11-12-70
11-25-70
Di scharge
0
0
0
0
.71
.07
.04
.09
.12
.05
Date
12-24-70
1- 6-71
1-26-71
6-30-71
7- 8-71
7-19-71
7-27-71
8- 3-71
10-19-71
2-25-72
Di scharge
0.02
.21
.01
.85
.28
.05
.80
.12
.38
.71
e/ Estimated.
141
Table 47. Discharge measurements, in cubic feet per second,
of Qamin Stream, Maap (16893500)
Location; Lat 9°35'57" N., long 138°10'15" E., 0.25 mi southeast of Qamin
and 0.8 mile upstream from mouth at altitude 45 ft (from topographic
map).2 Drainage area; 0.19 mi .
Period of record; 1980-81.
Date Discharge
9-19-80 0.49
10-20-80 1.2
3-24-81 .03
4. 8-81 0
7-18-81 .28
142
Miscellaneous measurements
Table 48. Discharge measurements, in cubic feet per second,made at miscellaneous sites
Stream
Dal i baech
Stream, Yap
Tribu tary to
Pacific
Ocean
MeasurementLocat ion
Lat 9°30'32" N.,
long 138 006'21" E.,
Date
9-21-65
9-23-65
Di scharge
0.19
.46
Dorfay Stream,
Gagi1-Tami1
(16893190)
Mukong
Stream
at inflow to reser
voir, 20 ft below
confluence of Tholomar
and Dinaey Streams, and
1.4 mi southwest of
Colonia (Confluence
covered by water
from new Gitaem dam
since 1975).
Lat 9°32'08" N.,
long 1380 10'13" E.,
at altitude 10 ft,
0.2 mi upstream from
mouth and 0.9 mi north
east of Tamilang School.
7-22-81
5-6-82
6-15-82
9-16-82
.93
.12
.22
.82
143
Water QualIty
Table 49. Chemical analyses of water from Qatliw (Atelu) Stream, Yap
Constituents
Time
Discharge, instantaneous -
Specific conductance -----pH
Temperature, water ------ -
Turbidity
Oxygen, dissolved ------
Hardness as CaCO,
Noncarbonate hardness ------
Calcium, dissolved (Ca) -
Magnesium, dissolved (Mg) --
Sodium, dissolved (Na) - Percent sodium ---
Sodium adsorption ratio
Potassium, dissolved (K)
Alkalinity, total as CaCO- -
Sulfate, dissolved (SO.) -
Chloride, dissolved (Cl)
Fluoride, dissolved (F)
Silica, dissolved (SiO,,) -
Solids, dissolved, sum of constituents ------
Solids, dissolved, tonper acre foot -- - -
Nitrite plus nitrate, as dissolved N -- --
Iron, dissolved (Fe) -------
Manganese, dissolved (Mn) --
Unit
ft3/s
umho
°C
NTU
mg/L
mg/L
mg/L
mg/L
mg/L
mg/L
percent
mg/L
mg/L
mg/L
mg/L
mg/L
mg/L
mg/L
ton/ac-f t
mg/L
yg/L ug/L
9-20-80
1230
0.18
125
7.4
26.5
5.4
7.0
47
0
5.6
8.1
6.8
24
.4
.3
51
.7
11
0
23
86
.12
.03
360
6
7-21-81
1200
1.0
83
7.9
26.0
7.8
35
5.1
5.5
6.2
28
.5
.1
24
3.9
12
0
20
67
.05
270
9
9-14-82
0930
8.4
70
7.6
26.0
32
5 4.6
4.9
5.3
27
.5
.2
27
9.5< .1
16
68
< .1
350
6
144
Table 50. Chemical analyses of water from Qaringeel (Aringel) Stream, Yap
Const ituent
Time ---- --_- ______ _
Discharge, instantaneous -
Specific conductance ___-__LJpH
Temperature, water - ----Turbidity -- ------------
Oxygen, dissolved ----- ---
Hardness as CaCO- -- ------
Noncarbonate hardness ----
Calcium, dissolved (Ca) ----
Magnesium, dissolved (Mg) --
Sodium, dissolved (Na) --- Percent sodium -
Sodium adsorption ratio ----
Potassium, dissolved (K) -
Alkalinity, total as CaCO -
Sulfate, dissolved (SO.)
Chloride, dissolved (Cl)
Fluoride, dissolved (F) -
Silica, dissolved (SiO )
Solids, dissolved, sum of constituents - -
Solids, dissolved, ton per acre foot -
Nitrite plus nitrate, as dissolved N - -
Iron, dissolved (Fe) --- --
Manganese, dissolved (Mn)
Unit 4-6-79
ft 3 /s
pmho
°C
NTU
mg/L
mg/L
mg/L
mg/L
mg/L
mg/L
percent
mg/L
mg/L
mg/L
mg/L
mg/L
mg/L
mg/L
ton/ac-f t
mg/L yg/L yg/L
1530 I/O
260
7.2
27. 5
2.8
91
10
10
16
13
23
.6
1.2
81
3.3
25
.1
35
153
.21
0
170
16
1-31-80 9-15-80 7-16-81 9-14-82
0900 I/O
220
6.8
24.5
5.0
74
8
8.0
13
17
33 .9
.6
66
2.9
23
0
25
147
< .20
3.9
90
3
1430
0.47
95 7.8
27.0
9.3
7.3
34
0
4.0
5.9
5.1
24
.4
.2
36
.3
7.7
0
19
64
.09
0
190
7
0920
0.17
68
7.7
24.5
7.9
28
7 3.8
4.5
4.3
25
.4
.1
21
2.2
6.2
0
18
52
.03
190
5
1230
20
45
7.2
26.0
20
0
3.6
3.0
3.7
29
.4
.2
20
6.0
< .1
9.5
48
< .1
190
5
Water sample taken from gage pool.
145
Table 51. Chemical analyses of water from Daloelaeb (Dalolab) Stream, Yap
Constituent Unit 1-31-80 9-17-80 7-16-81 9-15-82
Time 1015 1400 1035 1300
Discharge, instantaneous ftvs - 0 0.56 0.03 0.09
Specific conductance ymho 210 112 99pH 7.0 7.6 7.2 6.9
Temperature, water °C 25.5 26.0 25-5 27.5Turbidity NTU -- 30
Oxygen, dissolved -- ------ mg/L 1.6 7.5 3.8
Hardness as CaCO mg/L 81 39 38 43
Noncarbonate hardness --- - mg/L 1593
Calcium, dissolved (Ca) mg/L 9.2 4.7 4.5 5.9
Magnesium, dissolved (Mg) mg/L 14 6.7 6.6 6.9
Sodium, dissolved (Na) mg/L 10 6.1 7.0 6.1
Percent sodium percent 21 25 28 23
Sodium adsorption ratio ------ .5 .4 .5 .5
Potassium, dissolved (K) --- mg/L .2 .3 .1 .1
Alkalinity, total as CaCO mg/L 80 34 29 40
Sulfate, dissolved (SO^) mg/L .7 1.3 2.6
Chloride, dissolved (Cl) mg/L 16 13 20 10
Fluoride, dissolved (F) mg/L 0 0 0 < .1
Silica, dissolved (Si0 2 ) mg/L 28 16 19 18
Solids, dissolved, sum of
constituents mg/L 127 69 78 81
Solids, dissolved, ton peracre foot ton/ac-ft .17 .09
Nitrite plus nitrate, as
dissolved N mg/L .13 .11 .04 < .1
Iron, dissolved (Fe) yg/L 150 370 170 260
Manganese, dissolved (Mn) ---- yg/L 20 10 7 6
Water sample taken from gage pool.
146
Table 52. Chemical analyses of water from Peemgoy (Pemgoy) Stream, Yap
Const i tuent
Time ----- ______________
Discharge, instantaneous ---
Specific conductance -- ---»LJpH
Temperature, water ---------
Turbidity ------------------
Oxygen, dissolved --------
Hardness as CaCO -
Noncarbonate hardness ----
Calcium, dissolved (Ca) --
Magnesium, dissolved (Mg) --
Sodium, dissolved (Na) -----Percent sodium ------- --
Sodium adsorption ratio ----
Potassium, dissolved (K) ---
Alkalinity, total as CaCO -
Sulfate, dissolved (SO.) -
Chloride, dissolved (Cl)
Fluoride, dissolved (F) ----
Silica, dissolved (SiO_) ---
Solids, dissolved, sum ofconstituents -------------
Solids, dissolved, ton peracre foot ----------------
Nitrite plus nitrate, asdissolved N ------------
Iron, dissolved (Fe) -----
Manganese, dissolved (Mn) --
Unit
ft 3 /s
ymho
°C
NTU
mg/L
mg/L
mg/L
mg/L
mg/L
mg/L
percent
mg/L
mg/L
mg/L
mg/L
mg/L
mg/L
mg/L
ton/ac-f t
mg/L
yg/Lyg/L
4-7-79
1100
0.01
370
7.5
26.5
3.2
170
0
17
30
14
15
.5
.4
170
3.3
12
.1
61
241
.33
.11
130
50
2-1-80
0915
0.01
345
7.5
25.5
4.6
140
0
15
25
13
17
.5
.5
150
.4
14
0
51
210
.29
.29
260
30
9-17-80
1000
0.27
118
7.5
26.5
8.4
7.9
41
0
5.2
6.9
6.3
25
.4
.4
54
.2
10
0
18
79
.11
0
150
10
7-16-81
1235
0.08
100
7.6
25.5
6.0
38
94.3
6.5
6.8
28
.5
.1
29
2.0
17
0
22
77
.08
130
4
9-15-82
0930
0.68
7.4
26.0
3313
4.05.7
5.6
27
.5
.1
20
10
8.7
< .1
20
69
.47
350
5
147
Table 53. Chemical analyses of water from Taalgum (Talagu) Stream, Yap
Constituent Unit 2-1-80 9-17-80 9-15-82
Time 0830 1100 1000 3 1 /
Discharge, instantaneous ffYs - 0 0.56 0.25
Specific conductance ---- - pmho 134 112pH 6.6 7.1 7.0
Temperature, water -- °C 25.5 26.5 26.0Turbidity NTU 6.9
Oxygen, dissolved ----- - mg/L 1.6 7.4
Hardness as CaCO mg/L 46 40 35
Noncarbonate hardness ------ mg/L 306
Calcium, dissolved (Ca) mg/L 5.4 4.4 5.3
Magnesium, dissolved (Mg) mg/L 7.8 7.0 5.4
Sodium, dissolved (Na) mg/L 7.0 5-8 5.2
Percent sodium - percent 25 24 24
Sodium adsorption ratio -- .5 .4 .4
Potassium, dissolved (K) - mg/L .1 .4 .1
Alkalinity, total as CaCO- mg/L 43 43 29
Sulfate, dissolved (SO.) - mg/L .3 .6
Chloride, dissolved (Cl) mg/L 14 11 8.5
Fluoride, dissolved (F) mg/L 0 0 < .1
Silica, dissolved (SiOj mg/L 21 20 17
Solids, dissolved, sum of 69
constituents mg/L 82 75 69
Solids, dissolved, ton peracre foot ------ ---------- ton/ac-ft .11 .10
Nitrite plus nitrate, as
dissolved N mg/L .16 .01 < .1
Iron, dissolved (Fe) Ug/L 30 140 270
Manganese, dissolved (Mn) - ug/L 4 10 6
Water sample taken from-gage pool.
148
Table 5^. Chemical analyses of water from Burong Stream, Yap
Constituent Unit 2-1-80 9-18-80 7-17-81 9-17-82
Time 16^5 1030 1520 0830
Discharge, instantaneous ftVs -0 2.0 1.3 0.14
Specific conductance umho 15^ 105 92 101pH - 7.0 7.1 7.3 7.0
Temperature, water °C 26.5 26.0 26.0 26.5Turbidity NTU 26
Oxygen, dissolved - ------- mg/L 7»^ 6.5
Hardness as CaCO_ mg/L 55 39 37 ^3
Noncarbonate hardness - ----- mg/L 3073
Calcium, dissolved (Ca) mg/L 8.0 5.2 5.1 5.8
Magnesium, dissolved (Mg) - mg/L 8.A 6.2 6.0 7.0
Sodium, dissolved (Na) mg/L 7.3 5.6 6.3 5-^
Percent sodium percent 22 2k 27 21
Sodium adsorption ratio ------ -- .4 .A .4 .A
Potassium, dissolved (K) - mg/L .5 .3 .1 .1
Alkalinity, total as CaCO mg/L 52 A3 30 AO
Sulfate, dissolved (SO^) mg/L .A 1.1 3.1 < 5
Chloride, dissolved (Cl) mg/L 13 8.2 9-0 8.1
Fluoride, dissolved (F) mg/L 0 0 0 < .1
Silica, dissolved (SiO ) mg/L 20 -- 21 21
Solids, dissolved, sum of
constituents mg/L 9^ 60 69
Solids, dissolved, ton peracre foot ---- ton/ac-ft .13 .08
Nitrite plus nitrate, as
dissolved N mg/L 1.2 .36 .03 .21
Iron, dissolved (Fe) ug/L 60 380 260 81
Manganese, dissolved (Mn) ug/L 20 10 6 16
Water sample taken from gage pool.
Table 55. Chemical analyses of water from Hukong Stream, Gagil-Tamil
Const i tuent
Discharge, instantaneous -
Specific conductance -------
nH __-_ ______H n
Temperature, water -------
Oxygen, dissolved -
Noncarbonate hardness - -
Calcium, dissolved (Ca) ----
Magnesium, dissolved (Mg)
Sodium, dissolved (Na) ----- Percent sodium -----------
Sodium adsorption ratio ----
Potassium, dissolved (K) ---
Alkalinity, total as CaCO -
Sulfate, dissolved (SO.) ---
Chloride, dissolved (Cl)
Fluoride, dissolved (F) -
Silica, dissolved (SiO_) -
Solids, dissolved, sum of
Solids, dissolved, ton per
Nitrite plus nitrate, as dissolved N ---- _---
Iron, dissolved (Fe) -------
Manganese, dissolved (Mn) --
Unit
ft^s
ymho
°C
NTU
mg/L
mg/L
mg/L
mg/L
mg/L
mg/L
percent
mg/L
mg/L
mg/L
mg/L
mg/L
mg/L
mg/L
ton/ac-f t
mg/L
yg/L yg/L
4-7-79
1400
0.09
94
6.9
27.5
5.4
32
0
5.1
4.6
6.3
30
.5
.1
35 2.2
7.9
.1
11
59
.08
.01
140
80
2-1-80
1510
0.33
81
6.7
28.5
5.6
25
0
4.1
3.6
5.2
31
.5
.1
30
.4
6.6
0
9.3
48
.07
.06
290
560
9-16-80
0930
2.5
72
6.8
26.5
3.6
6.3
29
0
4.2
4.4
4.6
26
.4
.3
28
4.0
6.1
.1
9.3
50
.07
.23
950
200
7-19-81
1000
1.7
53 6.5
26.0
15
1
2.2
2.4
4.0
36
.4
.1
14
1.2
5.6
8.6
33
.02
100
90
9-16-82
1200
2.7
59 6.8
27.5
23
0
4.0
3.1
3.8
27
.4
.1
27 < 5
5.3< .1
7.6
< .1
430
100
150
Table 56. Chemical analyses of water from Eyeb Stream, Gagil-Tamil
Const i tuent
Time - ------- -
Discharge, instantaneous -
Specific conductance -- -_ LIpH
Temperature, water _____
Turbidity ________
Oxygen, dissolved -- ----
Hardness as CaCO- ________
Noncarbonate hardness -
Calcium, dissolved (Ca) ----
Magnesium, dissolved (Mg) --
Sodium, dissolved (Na) - Percent sodium ----- ------
Sodium adsorption ratio
Potassium, dissolved (K) -
Alkalinity, total as CaCO -
Sulfate, dissolved (SO.) ---
Chloride, dissolved (Cl)
Fluoride, dissolved (F)
Silica, dissolved (SiO ? )
Solids, dissolved, sum of constituents ----- ---
Solids, dissolved, tonper acre foot ------------
Nitrite plus nitrate, as dissolved N _____---
Iron, dissolved (Fe) -
Manganese, dissolved (Mn) --
Unit
ft3 s
umho
°C
NTU
mg/L
mg/L
mg/L
mg/L
mg/L
mg/L
percent
mg/L
mg/L
mg/L
mg/L
mg/L
mg/L
mg/L
ton/ac-f t
mg/L
vg/L yg/L
9-16-80
1130
1.9
69
6.8
26.5
1.4
6.9
21
5
5.6
1.7
4.1
29
.4
.3
16
6.9
6.0
0
7.2
44
.06
.43
390
40
7-18-81
1010
2.2
36
6.8
26.0
7.2
10
0
2.1
1.2
4.0
46
.5
.1
12
.6
5.2
0
7.6
28
.02
160
20
9-16-82
0915
2.5
41
6.9
26.5
13
0
2.7
1.4
3.6
38
.5
.1
16 < 5
5.3< .1
6.0
< .1
120
9
151
Tabl
e 57-
Chemical an
alys
es of wa
ter
from low-flow p
arti
al-r
ecor
d st
atio
ns on
Ya
p
Tama
ney
Ripu
Oina
ey
Thol
omar
___Stream____
____Stream___
____Stream
___Stream__
____
Constituent
Unit
9-17
-80
7-17-81
9-17
-80
7-17-81
9-18
-80
7-17
-81
9-18
-80
7-23-81
Time
1630
09*1
5 15
30
10*5
1630
11
35
1500
0920
Disc
harg
e, Instantaneous
ft3/
s 1.
* 0.47
1.5
0.43
0.14
0.06
0.43
0.
08
Spec
ific
co
nduc
tanc
e
pmho
138
161
112
152
92
81
130
116
pH
7.3
7.9
7.4
8.1
7.2
7.3
7.1
7.3
Temp
erat
ure,
wa
ter
°C
27.0
26;5
27.0
26.5
26.0
26.0
26.5
26.5
Turb
idit
y
NTU
12
19
22
--
27
Oxygen,
diss
olve
d
mg/L
6.4
7.4
7-7
7.2
7.5
6.5
7.6
6.5
Hardness as
Ca
CO
mg/L
62
72
48
67
35
31
44
47
Nonc
arbo
nate
ha
rdne
ss
mg/L 04 0142303
Calc
ium,
di
ssol
ved
(Ca)
mg/L
13
15
6.9
11
4.1
3-2
6.4
6.5
Magn
esiu
m, di
ssol
ved
(Mg) --
mg/L
7-2
8.3
7.4
9.6
6.1
5.5
6.9
7.5
Sodium,
diss
olve
d (Na)
mg/L
4.3
5.3
5.2
7.7
4.8
5.7
6.2
6.9
Percent
sodi
um percent
13
14
19
20
23
29
23
24
Sodium ad
sorp
tion
ra
tio
--
.2
.3
.3
.4
.4
.4
.4
.4
Potassium, di
ssol
ved
(K)
mg/L
.1
.1
.4
.1
.2
.3
.3
.2
Alkalinity,
tota
l as
Ca
CO.
- mg
/L
66
68
51
53
33
28
50
44
Sulfate, dissolved
(SO^)
mg/L
.6
1.3
.9
1.9
.9
2.0
.2
2.0
Chloride,
diss
olve
d (Cl)
mg/L
5-4
5.5
6.7
20
6.7
7.6
8.7
10
Fluo
rlde
, dissolved
(F)
mg/L
00
00 .1000
Silica,
diss
olve
d (SI0
2)
mg/L
18
16
20
22
20
20
19
22
Solids,
diss
olve
d, su
m
of co
nsti
tuen
ts
mg/L
89
93
79
104
64
61
78
82
Solids,
diss
olve
d, to
n
per
acre fo
ot --
-
ton/
ac-f
t .12
.11
.09
--
.11
Nltr
ite
plus ni
trat
e,
as di
ssol
ved
N
mg/L
.12
.03
.22
.03
.07
.02
.07
.04
Iron
, di
ssol
ved
(Fe)
pg/L
33
0 160
250
150
450
100
240
140
Manganese, di
ssol
ved
(Mn)
yg/L
20
40
20
20
30
9 10
10
Tabl
e 58.
Chem
ical
an
alys
es of
wa
ter
at low-flow pa
rtia
l-re
cord
st
atio
ns
and
mi seel laneous
M
onguch
Stream,
Gagi
1-Tami
1
Cons
t i tue
nt
Discharge, in
stan
tane
ous -
_ II
pH
Turbidity
Calc
ium,
dissolved
(Ca)
-
Magn
esiu
m, di
ssol
ved
(Mg) --
Sodium ad
sorp
tion
ra
tio
Potass
ium,
di
ssol
ved
(K) -
Alkalinity,
tota
l as
CaCO
-
Sulf
ate,
dissolved
(SO.
)
Chlori
de,
diss
olve
d (Cl)
Fluoride,
diss
olve
d (F
)
Silica,
diss
olve
d (Si0
2)
Solids,
diss
olve
d, su
m
Solids,
diss
olve
d, to
n
Nitrit
e plus nitrate,
Mang
anes
e, di
ssol
ved
(Mn)
Unit
ft's
limh
o
°C
NTU
mg/L
mg/L
mg/L
mg/L
mg/L
mg/L
percent
mg/L
mg/L
mg/L
mg/L
mg/L
mg/L
mg/L
ton/
ac-f
t
mg/L
Ug/L
1
ug/L
9-16
-80
1430
1.3
33 5.9
28.0
2.3
5.2
7 0 .8
1.1
3.7
53 .6
.6
8 1.8
6.3
0 6.7
26 .0
4
0
,000
110
7-22-81
1045
1.6
34 6.4
27.5 6.6
6 0
.8
.9
4.3
61 .8
.2
8 1.0
5.9
0 10 28
.02
120 20
9-16-82
1500
1.3
29 5.8
27.5 7 0 1.5 .7
3.4
51 .6
.2
9 <
5 5.7
< .1
4.4
< .1
580 44
site on Gagi 1 -Tamil and
Maap
Dorfay
Stream,
Gagi
1-Tami
17-22-81
1500
0.93
29 6.0
27.5 6.8
4 0
.5
.6
4.1
70 .9
.1
6 1.0
5.8
0 6.7
23
.01
200 30
9-16-82
1300
0.82
33 6.5
27.5 6 0
.2
1.3
4.2
60 .9
.2
10
< 5 5.4
< .1
6.0
< .1
320 34
Gilaew
Spring,
Gagi 1-T
ami
19-
16-80
1130
0.40
105 6.
6
27.0
.50
6.2
34 5 3-1
6.3
6.3
29 .5
.4
29 .4
9.7
0 15 63 .0
9
.88
100 20
7-18
-81
1540
0.25
111 7.
0
27.5 5.4
40 8 2.3
8.3
9.0
33 .6
.2
32 .5
20 0 18 78
.07
80 7
Qami
n
Stream,
Maap
9-19
-80
1600
0.49
131 7.
1
27.0
15 6.4
42 0 6.8
6.1
9.5
33 .4
.3
43 5.0
15 0 19 83 .1
1
.12
320 20
7-18-81
1250
0.29
120 7.
4
27.5 7.2
40 8 6.1
6.1
10
35 .7
.2
32 2.0
18 0 20 82
.04
420 50
For
Lyon Associates an
alys
es,
see
tabl
e 14.
Table 59. Chemical analyses of water from Airport Swampand Water Treatment Plant , Yap
Ai rport Swamp
Const i tuent
Specific conductance -------
nw _________________________pn
1 dll^Jd O C U 1 C, WO L. C 1
\/^ y y CI 1 , HI ODwIVdJ
Noncarbonate hardness
Calcium, dissolved (Ca) ----
Magnesium, dissolved (Mg)
Sodium, dissolved (Na) -- - Percent sodium -----------
Sodium adsorption ratio - -
Potassium, dissolved (K) -
Alkalinity, total as CaCO -
Sulfate, dissolved (SO.) -
Chloride, dissolved (Cl) ---
Fluoride, dissolved (F) ----
Silica, dissolved (SiO.) ---
Solids, dissolved, sum of constituents ----------
Solids, dissolved, tonper acre foot -- --- -
Nitrite plus nitrate, as dissolved N ---------
Iron, dissolved (Fe) ---
Manganese, dissolved (Mn) --
- Location: Lat 9°29'14" N. at old Yap airport. For
Unit
ymho
°C
NTU
mg/L
mg/L
mg/L
mg/L
mg/L
mg/L
percent
mg/L
mg/L
mg/L
mg/L
mg/L
mg/L
mg/L
ton/ac-f t
mg/L
ug/Lug/L
2-2-80
0930
125
7.7
26.0
41
1
13
2.1
5.5
22
.4
.5
40
4.7
9.2
0
2.3
61
.08
.01
50
9
, long 138°05'06 1967 analyses,
9-20-80
1030
110
7.3
33.0
15
6.3
43
2
14
2.0
4.5
18
.3
.7
41
3.3
7.8
.1
2.3
61
.08
.36
70
10
11 E., alt see table
7-20-81
1615
88
8.5
32.0
5.7
36
8
12
1.4
2.3
16
.2
.8
28
< 5
4.7
0
2.3
.02
60
40
itude 33 13.
9-15-82
1520
7.6
30.0
41
1
13
2.0
3.9
17
.3
.5
40
6
6.7< .1
1.9
58
< .1
49
11
.6 ft,
-^ Water treatment
plant9-20-82
1500
145
7.2
60
56
13
14
5.0
5.6
18
.3
.5
43
10
.1
11
88
.12
.12
160
30
2/ Finished water collected from rubber hose at plant.
154
Tabl
e 60.
Chem
ical
an
alys
es of water
from w
ells on
Ya
p an
d Ga
gII-
Tami
l
Const
i tue
nt
Time
Dept
h ___
____
____
pH . __
Calc
ium,
dissolved
(Ca) --
Magnesium, dissolved
(Mg)
Sodi
um ad
sorp
tion
ra
tio
Pota
ssiu
m, dissolved
(K) -
Alkalinity,
tota
l as
Ca
CO
-
Sulfate, dissolved
(SO.
) -
Chloride,
diss
olve
d (Cl)
Fluorlde,
diss
olve
d (F
)
Silica,
dissolved
(SIO
.,)
Solids,
diss
olve
d, su
m
Nitrite
plus nitrate,
Mang
anes
e, dissolved
(Mn)
Tim
lang
3 well,
Yap
Unit
9-15-82
ft ymho
°C
mg/L
mg/L
mg/L
mg/L
mg/L
percent
mg/L
mg/L
mg/L
mg/L
mg/L
mg/L
mg/L
mg/L
ng/L
ug
/L
1510
62 7.0
16 0 4.5
1.2
7-0
48 .8 .2
20
< 5 9.4
< .1
5.1 .69
340 22
Lam
aer
well
,
Yap
7-20-81
1550
91
177 6.
7
62 0 10 9.1
12
29 .7 .4
70 1.0
12 0
63
150
.11
60 0
C
ommu
nica
tion
Station
wel
1 , Ya
p2-
2-80
1100
81 7-7
26.0
25 0 4.4
3-4
6.3
35 .5 .4
30 1.2
8.2
0 29
72 .1
160
10
7-20-81
1400
82
119 6.
9
29.0
40 0 7.3
5.4
8.0
30 .5 .3
44
.3
7.4
< .1
58
114
.19
160 10
9-15-82
1600 7.0
40 0 7-2
5.3
7-8
30 .6 .6
49
< 5 8.0
0 57
.25
23
11
-Mit
sui
well,
Yap
7-20
-81
9-15-82
1440
16
30
85
125 7-
3 7.5
29.4
48
45
0
0 12
114.3
4.3
8.9
7.8
29
41
.6
.6.4
.5
56
49
1.0
< 5
7.9
8.4
0 <
.142
41
.13
.12
30
4
0 3
Mon
guch
1
well,
Gagi l-Taml
19-
16-8
2
1530 75 7.1
29.0
24 0 4.3
3-1
8.1
41 .8 1.8
30
< 5 6.9
< .1
80
.31
8 2
~* Latitude 9°
29'l
6" N.
, lo
ngit
ude
138°
05'0
4" E.,
alti
tude
44 ft.
-
Lati
tude
9°
29'0
3" N.
, long
itud
e 138°05'11" E.,
alti
tude
35 ft
.
$/ La
titu
de 9°
29'2
5" N.
, longitude
138°
05'0
3" E.,
alti
tude
38
ft.
-
Lati
tude
9°
29'2
7" N.
, longitude
138°
05'0
2 E.,
alti
tude
30 ft.
& La
titu
de 9°
31'5
9" N.
, longitude
138°
09'5
7" E.,
alti
tude
21
ft
.
Table 61. Chemical analyses of water from Airport and Tamil aquifers (1982)
[Source: Nance, 1982. Samples analyzed by Brewer Analytical Laboratories, Honolulu, March 15-31, 1982]
Const i tuent
pH
Turbidity -- -
Calcium --------
Magnesium -- -
Sodium ----- -
Potassium -- -- -
Chloride ----------
Fluoride --- -----
Silica --------
Total dissolvedsol ids -------
Nitrate ---------
Arsenic --
Barium - -
Cadmium --- -
Chromium - ---
Lead
Mercury ------ -
Selenium --------
Silver ----
Unit
-- NTU
mg/L-- mg/L
-- mg/L
mg/L
-- mg/L
-- mg/L
mg/L
-- mg/L
-- mg/L
mg/L
mg/L-- mg/L
-- mg/L
mg/L-- mg/L
-- mg/L
-- mg/L
Timlang 1well, Yap2-20-82
6.6
.2
2.4
4.3
1.9
.39
24
.35
19
90
< .19
< .002
< .1
< .005
< .05
< .05
.086
< .002
< .01
Mukong Streamwell,
Gagi 1 -Tami 11-26-82
7.3
3.9
1.2
1.3
66.5
4.0
89
.64
26
346
< .01
< .002
< .1
< .005
< .05
< .05
.158
< .002
< .01
Monguch 2well,
Gagi 1 -Tami 11-30-82
7.0
.5
2.1
3.2
2.5
1.3
20
.35
49
123
< .01
< .002
< .1
< .005
< .05
< .05
.400
< .002
< .01
Note: For chemical analyses of Timlang 3 well, Yap, and Monguch 1 well,
Gagil-Tamil, by U.S. Geological Survey, see table 60.
156
Table 62. Water and air temperatures and instantaneous discharge
Date
Sept. 20, Oct. 21, July 21, Feb. 12, Mar. 25, July 14, Sept. 14,
1980 1980 1981 1 Qfi 0
1982
1982
1982
at Qatl i
Time
1 O "2 C ioi> - 1210 -
i o nn 1140 -
1 1 1 C - 1115 1 1 ftC-- ijlo -
0940 -
iw (Atelu) Stream, Yap
1 nstanta neous
di scharge
(ft 3 /s)
0 1 O
.___ 1 7 ______1 /- 1.0 -- .05 -
24 __ - *.*T. .05 -.... 9.9 .
Tempera ture
water(°0
o/l r
o/i AZb.U - -- o/i A
. __ oc c __ _.*-j j oc c _ __.*-j j o/i A
0/1 A
Tempera ture ai r(°C)
27 ^*-i »j
27 nL. 1 * U
oA c
27 ^t-i j---- 27 ^* /..?
Table 63. Water and air temperatures and instantaneous dischargeat Qaringeel (Aringel) Stream, Yap
Date
Sept. Oct. Oct. Nov. Nov. Dec. Dec. Jan. Jan. Feb. Feb. May 1 July Oct. Oct. Oct. Nov. Nov. Dec. Dec. Jan. Jan.PeK
1830,'
13,2,'
18, 6, 22,3,1,'
14, 2,29,'
16,'
18, 8, 26, fi
, 1969
1969 -1969 - 1969 -
1969 -1969 -
19701970 -
1970 -1970 -
1970 1970 -
1970 -1970 -1970 -
1970 -1970 -1970 -1970
1971 1971
1Q71 .
Instanta- Tempera- Tempera- neous ture ture
discharge water air
Time (ftvs) (°C) (°C)
- 0850 ----- 0930 -- 1230 - 1400 . 0920 - 1550 - 1045 - 0935 - - 1330 - 1310 - 0935 - 0955 - 1400 - 1405 - 1100 - 1400 - 1415 - 1015 - 1410 - 1510 - 1115 - 1400 iQLc. _
0.11
co __ -- _ -. j*-
O *7
.11
.05 -
.06
.06
.42 2.0 .09 -
1.7 .05
1.1
O Q
.24 3.2
12 - 1 fc
i L _________
24.0 26.0
25-5 26.0 24.0 25.0 26.0 26.0 26.0 26.0 27.0 26.0 26.0 26.0 26.0 26.0 27.0 25.0 25.0 oc. n
157
Table 63. Water and air temperatures and instantaneous discharge
Date
Feb. 25, 1971 Mar. 25, 1971 Apr. 28, 1971 Dec. 3, 1971 -Jan. 13. 1972 Mar. 24, 1972 Apr. 21, 1972 June 15, 1972 July 16, 1972 Aug. 11, 1972 Sept. 19, 1972 --Oct. 13, 1972 Nov. 10, 1972 Dec. 21, 1972 Dec. 22, 1972 June 4, 1973 July 5, 1973Aug. 1, 1973 -Aug. 31, 1973 Sept. 20, 1973 --Oct. 19, 1973 Dec. 26, 1973 July 14, 1974 July 30, 1974 Sept. 13, 1974 --Oct. 9, 1974Nov. 5, 1974 Dec. 6, 1974 Dec. 30, 1974 Jan. 14, 1975 May 2, 1975 May 15, 1975 -June 17, 1975 July 14,1975 -Aug. 14, 1975 Aug. 28, 1975 Sept. 22, 1975 -Oct. 7. 1975Dec. 4, 1975 -Dec. 22, 1975 Jan. 5, 1976 Feb. 3, 1976June 16, 1976 July 6, 1976
at Qaringeel
Time
1000 . 0930 1415 1450 ....... 1455 - -- 0835 1200 1445 1320
. 0850 1435 0930
1450 1420 1400 1020 1415 1440 1435 - 1355 1440 1500 1516 - 1435 1400 1453 1050 1414 1044 1354 - 0945 T040 0810 0920 1400 1015 0940 1440 1040 1230 1405 1630 1010 0940
(Aringel) Stream,
I nstantaneous
d^i scharge
(ft 3 /s)
0.89 - .19 ..... .47 ........... .03 ------..... .09..... .64..... .03 ..... .09 ...... .02 .46 ........... .36 ...... .02 .14 ........... .06 - ..... .03 ...... .16 .12 ..... .37 ........... .07..... .45 ...... .10 ..... .47 ....... .25 ... ~ .71 .26 ..... 1.6 ......----- 2.9..... .69 ........... .94 ...... .10 ..... .13 ........... .99 ........... .34 ........... 5.6 ............ .77 ........... .28 ..... . 51 ... ..... .87 ........... .87 ........... .58 ...... .06 ..... .25 ........... . 17 ......
_ 1 n» 1 U
Yap--Cont inued
Temperaturewater(°C)
-- 25.0-- 25.0 26.0-- 27.0 25.0 25.0-- 25.0-- 25.0 26.0 25.0-- 26.0-- 25.0-- 29.0 -- 26.0-- 27.0-- 27.0-- 27.0-- 27.0 27.0-- 27.0 27.0- 26.5-- 25.5-- 26.5 - 26.5 - 26.0 26.0 .. 26.0 ~ 25.5 -.. 26.0 25.0 26.0 26.0 25.0 27.0 -- 25.0 -- 25.0 -. 26.0 .. 25.0 27.0 .. 26.0 ~ 25.5 --. 25.0 -- 24.5
Temperatureai r(°C)
- 28.0
- 30.0- 30.0- 28.0- 29.0- 27.5- 26.5- 31.0- 29.0- 29.0- 29.0- 27.0- 30.0- 26.0- 28.0- 29.0- 27.0- 32.0- 34.0- 27.0- 28.0- 28.0
158
Table 63. Water and air temperatures and instantaneous dischargeat Qaringeel (Aringel) Stream, Yap Continued
Instanta- Tempera- neous ture
discharge water
Date
July 26, 1976 Aug. 10, 1976 Aug. 26, 1976 Sept. 16, 1976 Nov. 2, 1976 Dec. 2, 1976 Dec. 29, 1976 Jan. 21, 1977 May 31, 1977 June 30, 1977 Aug. 12, 1977Nov. 1, 1977 Nov. 29, 1977 Dec. 15, 1977 - Dec. 30, 1977 -----Feb. 1, 1978 June 15, 1978 ---June 28, 1978 .........July 21, 1978 Aug. 30, 1978 Sept. 19, 1978Sept. 29, 1978 -----Oct. 26, 1978 Nov. 9, 1978 Nov. 28, 1978 Dec. 13, 1978 Mar. 15, 1979 May 15, 1979 June 13, 1979 June 27, 1979 July 11, 1979 July 26, 1979 Aug. 8, 1979 Aug. 21, 1979Oct. 15, 1979Oct. 30, 1979Dec. 26, 1979 May 19, 1980 June 3, 1980 June 30, 1980 July 24, 1980 July 31, 1980 Sept. 2, 1980 Sept. 15, 1980
Tempera ture ai r
Time (ft 3 /s) (°C) (°C)
1400 1520 1415 1320 1500 1235 - -1510 0950 1500 1515 1350 13501400 1450 093013501415 1430 1355 -----1515 - --0935 --0910 1505 1440 1410 09351330 -1505085509151200 1020 0915 -----0945 - -1445 ______1400 1010 1025 1405 1030 0900 1055 0940 1430
0.73 .........20 .76 -.48 .13 -----.51 -----
1.7 -.36 .08 .06 .07 .........01 .09
1.8 -----.01 .04 .06 .05 -.03 - .07.31 .........30 .........17 ... .49.07 -
3.7 .29 -----.16 .53
1.1 2.3 -1.7 --.54 -.!6 .12 .12 .21 .07 ----- .17 .........35 - .26 --------.06 - .07 -.47
26.0 -26.0 -25.0 -26.0 -27.0 -25.0 -27.0 24.0 -26.0 -26.0 -28.0 -26.0 -26.0 26.0 25.0 -25.5 26.5 -26.5 27.0 -28.0 25.5 26.0 -26.5 26.0 -26.0 -25.5 26.5 27.0 25.5 26.0 26.5 25.5 25.5 25.5 27.0 26.0 -25.0 -26.0 -26.5 25.5 -25.0 -25.5 -25.5 27.0 -
- 27.0 - 27.5 27.5- 30.0 29.5 - 27.5. 29.0 25.5- 28.0- 30.0 31.0 - 32.5- 30.5- 28.5 27.0- 27.0- 30.0- 30.5- 30.5- 30.0- 28.0---- 28.0- 32.0- 30.0--- 30.5 26.5.... 35.0- 32.0 26.5 - 26.5- 29.0- 26.5 27.5- 28.5. 29.0- 29.0- 27.0 - 27.5- 30.0 27.5- 25.5- 30.0 27.0- 30.0
159
Table 64. Water temperature and instantaneous discharge
Date
Oct. 16, 1969 July 14, 1970 Oct. 5, 1970 Oct. 30, 1970 Nov. 12, 1970 Nov. 25, 1970 Jan. 5, 1971 Mar. 23, 1972 Apr. 20, 1972 July 16, 1972 Aug. 10, 1972 Sept. 20, 1972 Oct. 12, 1972
at Faraq
Time
0920 0900 1510 1415 1520 1415 1300 1010 1010-- 1535- 1555 1450______ i_rci-op
(Fara) Swamp outlets,
I nstanta- neous
di scharge
(ft3/s)
O f)£__________ .07 - .49 ----- .!/, __. ___ 12 -----
1 £.
99 _____
- .03 -__________ 19 _____
.04 n/i _ _ _
.16 - .30 - .06
Yap
Tempera ture water(°c)
--- ?£, C,f-j j f\f noft n--- ZO.U o£ n
27.0 o£ no£ no£ no£ n
29.0 oft noft noft n
Table 65. Water temperature and instantaneous dischargeat Galngun Swamp outlet, Yap
Date
Sept. 18, 1970 Oct. 5, 1970 Oct. 29, 1970 Nov. 13, 1970 Nov. 25, 1970 Dec. 22, 1970 Jan. 5, 1971 Jan. 28, 1971 Jan 13, 1972 Mar 23, 1972 Apr. 20, 1972 May 18, 1972 July 15, 1972 Aug. 10, 1972 Sept. 19, 1972 C\r+ 19 1079
Time
1415 1335 0945 0855 1340 1330 - 1450 0845 1030 0930 - 0935 - 1317 1003
1 co o 1610 - _ 1/ion __.
Instanta neous
discharge
(ft 3 /s)
- 0.15 ______ 23 .. - j /+0 . ~ \j______ 9C _____ O ___________ .34 ___________ .23 ~ 1/1
I
- .30 -o£
_ .29 - .17 -_ .16 -_ .20 - .21 ______ .50 -_ ___ 97 _____
Tempera ture water(°0
O£ C
0-7 n
O/I n
oc no£ nO/I n--- Zb.U o£ nor no c c OO oc noc noc no£ noc no/i n --- Zb.U
___ 9A n
160
Table 66. Water and air temperatures and instantaneous discharge
Date
Sept. 19, 1969 Oct. 14, 1969 Nov. 6, 1969 Nov. 20, 1969 July 14, 1970 Sept. 2, 1970 Sept. 22, 1970 Oct. 6, 1970 Oct. 29, 1970 Nov. 13, 1970 Nov. 25, 1970 Dec. 23, 1970 Jan. 5, 1971 Jan. 27, 1971 Jan. 13, 1972 Apr. 20, 1972 July 15, 1972 Aug. 10, 1972 Sept. 20, 1972 Oct. 12, 1972 Mar. 11, 1974 July 14, 1974 Sept. 13, 1974 May 2, 1975 June 20, 1975 July 15, 1975 Aug. 29, 1975 Oct. 9, 1975 Dec. 5, 1975 Jan. 9, 1976 Apr. 2, 1976 May 21, 1976 July 6, 1976 Aug. 11, 1976 Dec. 3, 1976 Jan. 21, 1977 Nov. 30, 1977 Feb. 1, 1978 June 29, 1978 Oct. 30, 1978 Nov. 30, 1978 June 29, 1979 Aug. 21, 1979 Dec. 27, 1979 Sept. 17, 1980 Oct. 20, 1980
Time
1605 1610 1535 0840 0935- 0855 1050 0930 1100 1010 1455 1400 1600 1600 1310 1100 1107 1637 1530 1540 1355 1722 - 1151 1325 0835 1020 0920 1310 1515 1445 1515 1025 1500 1345 1205 1440 1325 1535 1056 0950 1415 1550 1531 1330 1630 1530
at Tamaney Stream,
1 nstanta-neous
discharge
(ft3 /s)
0.45 .15 .24 .06 -- .07 ----- 3.8 - .38 - .10 -- .07 .14 ----- .38 - .04 - .13 .04 .06 .08 .06 .08 - .09 .02 .20 .26 .27 .25 - - 1.5 ----- - .52 - .23 - .14 .12 .04 .32 .15 .09 -------- .74 - .23 .26 .... .07 - .05 - - .09 .10 .10 .8! - - .05 - - - .16 - L4 1.1
Yap
Temperaturewater(°0
26.5 25.5 25.5 25.5 26.0 26.0 26.5 26.0 27.0 25.0 26.0 26.0 27.0 26.0 25.5 25.0 26.0 26.0 26.0 26.0 26.5 25.5 26.0 27.0 27.0 27.0 26.0 25.0 34.0 27.0 27.5 26.0 27.0 26.0 25.0 26.0 26.0 26.5 29.0 26.0 28.0 27.0 27.0 25.5 27.0 27.0
Temperatureai r(°0
28.0
29.0 28.0 28.0 29.0 32.0 27.0 36.0 30.0 29.5 32.0 32.0 28.0- 26.5- 27.5- 27.5 30.0- 30.5- 27.5-- 30.0 30.0 30.0 30.0
29.0
161
Table 67. Water and air temperatures and instantaneous discharge
Date
Mar. 7, 1968 Sept. 19, 1969 Oct. 16, 1969 Nov. 4, 1969 Nov. 20, 1969 July 14, 1970 Sept. 2, 1970 Sept. 22, 1970 Oct. 7, 1970Oct. 30, 1970 Nov. 13, 1970 Nov. 27, 1970 Dec. 22, 1970 Jan. 5, 1971 Jan. 26, 1971 Jan. 13, 1972 Mar. 23, 1972 Apr. 20, 1972 May 18, 1972 July 15, 1972 Aug. 10, 1972 Sept. 20, 1972 Sept. 20, 1973 Oct. 12, 1973 Mar. 11, 1974 July 14, 1974 Sept. 13, 1974 May 2, 1975 June 20, 1975 July 15, 1975Aug. 29, 1975 ~Oct. 9, 1975 Dec. 5, 1975Jan. 9, 1976 Apr. 2, 1976 May 21, 1976 July 2, 1976 Aug. 11, 1976 Dec. 3, 1976 - -Jan 21, 1977 Nov. 30, 1977Feb. 1, 1978 Aug. 31, 1978Oct. 30, 1978
Time
1630 - 1540 - 1110 - 1015 - 0925 - 1015 - 0925 - 1500 - 1500 - 1525 - 1110 - 0900 - 1425 1510 - 1500 - 1332 - 1245 1135 -.... 1435 . 1136 1720 - 1600 - 1440 - 1610 - 1425 - 1617 1523 - 1258 - 1110 0940 0900 - 1355 - 1415 - 1510 - 1420 - 1050 - 1440 1326 - 1130 - 1405 - 1410 - 1515 0910 0935
at Ripu Stream, Yap
I nstantaneous
di scharge
(ft 3 /s)
. 0.63
........ .43 .......
. . . 19 ....- .15 - - .07 - . .10 - -- 3.3. .21 - .16 . .06 . .16 . .62 - .09 . .06 . .12 . .n ........ .34 ........ . .09 -. .004 . .08 . .22 . .!6 . .. .27 - . .04 . .20 . .20 . .21 . .22 . 1.6 - ........ .85. .33 - .17 - .93 - .07 . .84 . .12 .. ... .09 . . .86........ .43 -----. .16 . .08 . .01 - -- .13 - .11
Temperaturewater<°C)
- 26.0 -- 25.5 -- 25.5- 25.5- 25.5- 26.0- 25.5- 25.5- 27.0- 27.0- 25.0- 26.0- 26.0- 27.0- 26.0- 25.0- 25.0- 25.0- 27.0- 26.0- 26.0- 26.0- 28.0- 26.0- 26.5- 25.5- 26.5 - 27.0 . 27.0 - 26.0 - 26.5 - 27.0 - 29.0 - 26.0 - 25.0 - 26.0 - 25.5 . 25.5 . 24.0 - 26.0 - 26.0 - 26.0 - 26.5 - 26.0
Temperatureai r(°c)
- 28.0 28.0
- 28.5- 32.0- 29.0- 29.0- 29.0- 29.0- 32.0- 29.0- 26.5- 29.0- 32.0- 28.0.... 25.5- 27.0- 27.0- 30.0- 28.0- 27.5
162
Table 67. Water and air temperatures and instantaneous dischargeat Ripu Stream, Yap Continued
Nov. June Aug. Dec. Sept Oct.
Date
30, 1978 -----9 Q 1 Q7 O
91 1979 -----*- ' , 'J/J97 1979 -----
. 17, 1980 -91 iQftn _____
Time
- 13^5 i co r~---- 1525 -'
1515
i "3 r c~- 1355 -'
____ 1530 ---. 10^5
1 nstanta- neous
di scharge
(ft 3 /s)
- 0.11 - 1.2 . .14 -
*c*~?
Tempera ture water
97 n_ 97 n
o£ n
27.0o__ n
Tempera ture ai r
.___ 30.5 32.0
oQ n --- 2.0.0 - 31.5
- 27.5
Table 68. Water and air temperatures and instantaneous discharge
Sept Oct.
1 1 1 1 W
Date
1 Q i oQ n
21, 1980 -----17 1QR1 _____
at
Time
1 f. i r
1010 ____ iiAn .
Dinaey (Dinay) Stream,
1 nstanta- neous
di scharge
(ft 3 /s)
________ 1Q ________.1.7._ __ __ nA __ __ __
Yap
Tempera ture water
o£ n
1^1 C
9A C __.
Tempera ture ai r
- 27.5 .___ 97 c:
163
Table 69. Water temperature and instantaneous discharge
Date
Sept. 30, 1969 -Oct. 14, 1969 Nov. 4, 1969 July 14, 1970 Sept. 2, 1970 Sept. 23, 1970 -Oct. 6, 1970 Oct. 29, 1970 Nov 13 1970 -- lilUV . ' J 1 > J 1 v»
Nov. 27, 1970 Dec. 22, 1970 Jan. 6, 1971 Jan. 27, 1971 Jan. 13, 1972 Apr. 20, 1972 Mav 18 1Q72 --- i id y \ \j ^ t j / £.
July 15, 1972 Aug. 11, 1972 Sept. 20, 1972 -Oct. 13, 1972 Jan. 11, 1973 Mar. 11, 1973 Sept. 18, 1980 -Oct. 21, 1980 lulw 97 IQfll .
at Tholomar
Time
- 1010 - 1245 -- 0920 - - 1045 -....... 0950 -....... 1330 -- 1330 - - 1600 --- 1410 -- 0920 - - 1450 -- 1020 -- 1420 -- 1400 -- 1215 -- 1507 -- 1213 - . TQ06 -. T645 -
1 i o£
1017 -------- 1 C 1 9 -
. ^50 -- 0915 -.- ___ naLn -
(Thalomar) Stream, Yap
Instanta neous
di scharge
(ft3 /s)
0.64 3 o-------- oZ ------OC.^5 -- --'nQ
3 Q-------- ^.Q
9A
oft--__-___ .20 ---------
.11 .
O O-------- .22 --_ ___.
........ .70 .........
........ .16 1 Q
. 10
.n . .09 . .01 .06
O 1--___--_ .2] _-____. ,!4 ......... .03
no---__-__ .jj^ ___-____. o o- - .23
- - /i7 .» ~ J 3 ) .32 -
- -- 07 .
Tempera ture water(°c)
o£ n )(. r\
o£ no£ n )(. n
yf. n
f)f n
o£ no£ no£ no£ no£ n0£i 0f-J . U
o£i n£. ̂ U
- 25.0o£ n )(. r\
- 25.0 o£ n9^ 0f-J . U
oQ nZo.u0^ c.
oA c.o£ c- 26.5
- 9A C
164
Table 70. Water and air temperatures and instantaneous discharge
Date
Sept. 30, 1969 Oct. 27, 1969 Nov. 13, 1969 Nov. 25, 1969 Oct. 3, 1970 Oct. 14, 1970 Oct. 28, 1970 Nov. 10, 1970 Nov. 24, 1970 Dec. 17, 1970 Dec. 19, 1970 Jan. 11, 1971 Feb. 12, 1971 Feb. 26, 1971 May 11, 1971 Mar. 24, 1972 June 16, 1972 Aug. 11, 1972 Sept. 20, 1972 Oct. 13, 1972 Nov. 10, 1972 Aug. 3, 1973 Sept. 21, 1973 Oct. 16, 1973 July 11, 197^ July 30, 197^ Oct. 9, 197^ Nov. 6, 197^ Dec. 11, 197^ Dec. 31, 197^ - Jan. 14, 1975 May 20, 1975 June 17, 1975 July 14, 1975 Aug. 14, 1975 Aug. 28, 1975 Sept. 22, 1975 Oct. 8, 1975 Dec. 5, 1975 Dec. 23, 1975 Feb. 3, 1976 Apr. 2, 1976 May 20, 1976 July 27, 1976
at Daloelaeb
Time
.... 133 o - 0855 - - 1020 - 1110 - 1045 - 0930 - 1030 - 1415 - 1315 - - 1050 - 1025 - 1350 -- - 1045 - 1405 - 1110 - 1210 - 0910 - 1240 - 1110 -.... 1345 ........ 1030 -.... 1330 ........ 1510 - 1500 - 1456 - - 1015 - 1621 - 1525 - 1403 - 1518 - 1455 - 1515 - 1035 - 1040 - 1032 - 1150 - 1045 - 1440 - 1020 - 1250 - 1110 - 1325 1435 . - 1^35 -
(Dalolab)
I nstantaneous
di scharge
(ft 3 /s)
-- 0.08 .40
-- e/.Ol - .28 --
.02 - 2.2
.02 - .56 -- .23 --
.16
.02 - .07 -- .16 --- .03 -
.02
.12
.04 - .03 --
.04
.003 -
.06 - .15 --- 1.4 --.. .25 -
.08 - .31 --- .27 -._ .29 -
.01 - .77 --
.01 - .25 -
.20 - 2.2 - .23 -- .25 --- .17 -
.04 - .78 --- .14 --- .05 --- .07 -
.08 - .07 --
Stream, Yap
Temperaturewater(°0
26.0 25.5- 25.5 25.5 26.0 24.0 25.0 26.0 26.0 26.0 26.0 26.0 25.0 25.0 25.0 25.0 25.0 25.0 25.0 25.0 29.0 - 27.0 26.0 27.0 26.0 25.5..__ 26.0 - 26.5 - 26.0 - 25.0 - 25.5 - 27.0 - 26.0 - 26.0 - 26.0 - 25.0 - 26.0 - 26.0 - 25.0 - 26.0 - 25.5 - 25.0 -...... 27.5 -- 25.0 -
Temperatureai r(°0
- 27.0
27.0 28.0 28.0 29.5 29.0 30.0 29.0- 29.0 29.0 28.0 30.0 29.0 29.0 27.0 29.0 26.0 26.5 30.0 27.0
165
Table 70. Water and air temperatures and instantaneous discharge
Date
Aug. 11, 1976 Aug. 26, 1976 Sept. 16, 1976 -Dec. 2, 1976 -Dec. 30, 1976 Jan. 21, 1977 Aug. 12, 1977 Sept. 29, 1977 -Nov. 29, 1977 Dec. 16, 1977 Sept. 19, 1978 -Sept. 29, 1978 -Oct. 30, 1978 Nov. 15, 1978 Dec. 13, 1978 Mar. 15, 1979 June 13, 1979 June 29, 1979 July 11, 1979 July 26, 1979 Aug. 8, 1979 Aug. 21, 1979 Oct. 10, 1979 Dec. 26, 1979 June 3, 1980 June 30, 1980 July 23, 1980 July 31, 1980 Sept. 2, 1980 Sept. 17, 1980 -Oct. 8, 1980
at Daloelaeb
Time
- 1250 . 1510 . 1420 .. 1330 - 1030 - 1025 - 1450 - 1015 - 1440 - 1205 . 1030 - 1010 - 0905 - 0900 - 1125 . 1450 - 0940 - 1005 - 1055 - 1115 - 1110 - 1135 - 0925 - 1055 - 1500 - 1020 - 1040 - 1020 - 1025 - 1400 - 1155
(Dalolab) Stream,
1 nstantaneous
di scharge
(ft 3/s)
0.10 ----- .28 - .17 - .16 ----- .07 -- .14 -- .07 - .01 .01 .10 - .09 - .08 .02 .13 1.0 .02 .12 .61 -__-_ .84 1.1 .08 .02 .12 .02 - .03 -_____ .07 ----- .08 .02 _____ .03_____ .56 - .13
Yap Cont inued
Temperaturewater(°c)
26.0 26.0 26.0 26.0 25.5 25.0 26.0 26.0 26.0 26.5 25.5 27.0 26.0 25.5 25.5 26.0 25.5 26.0 26.0 25.5 25.5 26.0 26.5 25.0 27.0 26.0 26.0 26.0 25.5 26.0 25.0
Temperatureai r(°0
- 27.5- 27.5- 28.5- 27.0- 27.5-- 26.5 28.5 29.0-- 29.0- 28.0 27.0 29.0- 27.5 28.0~ 26.5-- 29.5- 27.0-- 29.0 28.0-- 26.5-- 26.0-- 32.0-- 27.5 26.5- 30.5 29.0 29.0 29.0 26.0
-- 27.0
e/ Estimated.
166
Table 71. Water and air temperatures and instantaneous discharge
Date
Oct. 9, 1969 -Oct. 27, 1969 Nov. 18, 1969 Dec. 30, 1969 Jan. 22, 1970 Oct. 15, 1970 Nov. 10, 1970 Nov. 24, 1970 Dec. 17, 1970 -----Dec. 19, 1970 Jan. 11, 1971 Jan. 27, 1971 -Feb. 12, 1971 Feb. 26, 1971 Mar. 26, 1971 May 11, 1971 - Dec. 4, 1971 Jan. 13, 1972 Mar. 24, 1972 June 16, 1972 Aug. 11, 1972 Sept. 20, 1972 Nov. 10, 1972 Aug. 3, 1973 Sept. 21, 1973 Nov. 20, 1973 Mar. 11, 1974 Apr. 5, 1974 July 11, 1974 July 30, 1974 Sept. 11, 1974 Nov. 7, 1974 Dec. 12, 1974 Jan. 14, 1975 May 14, 1975 June 17, 1975 July 14, 1975 Aug. 14, 1975 Aug. 28, 1975 Sept. 22, 1975 Oct. 9, 1975 Dec. 4, 1975 Dec. 23, 1975
at
Time
1400 1020 1020 1115 1025 1045 1600 1450 1225 1200 1500 1120 1200 1530 1645 1245 1100 1210 1410 1120 1420 1335 1230 1505 1655 1435 1005 1206- 1709 1240 1557 1627 1533 0954 1400 1410 1440 0955 1505 1445 0850 1350 1040
Peemgoy (Pemgoy)
I nstantaneous
di scharge
(ft 3 /s)
0.08 ........ .38 - .30 - .06 2.0 .59 - .68 - .29 -........ .67 .. ... .06 - .06 .03 -........ .29 - .06 .03 .03 - . .04 -- .10 .20 ........ .}8 - .11 .08 . .13 ._ .!6 - 3.0 -........ .73 .. .01 .08 - .20
.52 -.. .05 -........ el 4 .......... .54 .. .05 -- .02 .26 1.4 -- .50 - .20 . j6 - .33 ._ .^0 --........ .08 -
Stream, Yap
Temperaturewater(°c)
26.0 26.0 26.0 25.0 25.0 25.0 26.0 26.0 25.0 26.0 26.0 25.0 25.0 26.0 26.0 26.0 25.0 25.0 25.0 25.0 25.0 26.0 28.0 26.0 26.0 28.0 25.5 26.5 25.5 25.5 - 25.5 - 26.0 - 25.5 - 25.0 - 27.0 - 26.0 - 26.0 - 25.0 - 26.0 - 26.0 - 25.0 - 26.0 - 25.0 -
Temperatureai r<°C)
- 27.0 26.5 27.0- 28.0 29.5 32.0- 28.0- 28.0 27.0 28.0 29.0 29.0 29.0 28.0
167
Table 71. Water and air temperatures and instantaneous dischargeat Peemgoy (Pemgoy) Stream, Yap Continued
Instanta- Tempera-
Date
Jan. 27, 1976 Feb. 3, 1976 Feb. 17, 1976 Mar. 2, 1976 Apr. 2, 1976 May 3, 1976 May 20, 1976 June 16, 1976 July 6, 1976 July 27, 1976 Aug. 11, 1976 Sept. 17, 1976 Nov. 2, 1976 Dec. 3, 1976 Dec. 30, 1976 Jan. 21, 1977 Aug. 5, 1977 Sept. 28, 1977 Sept. 29, 1977 Nov. 3, 1977 Nov. 18, 1977 Nov. 30, 1977 Dec. 16, 1977 Dec. 29, 1977 Jan. 18, 1978 Feb. 3, 1978 Feb. 23, 1978 Mar. 16, 1978 Apr. 12, 1978 May 26, 1978 June 16, 1978 Aug. 30, 1978 Sept. 29, 1978 Oct. 31, 1978 Nov. 15, 1978 Nov. 30, 1978 Dec. 13, 1978 Mar. 16, 1979 June 13, 1979 June 29, 1979 July 11, 1979 July 26, 1979 Aug. 8, 1979
Time
1340 1015 1055 1445 1205 1445 1110 1400 1045
1110 0930 1245 0945 1120 1225 1320 - 1515 0945 0915 0920 1515 0935 1405 1250 0920 1455 0955 1335 0920 0900 1335 1050 0935 0955 0905 1245 0910 1440 1140 0920 1240 1315
neousdi scharge
(ft 3 /s)
0.20 . n ........ .03........ .07........ .10 .09 . 10 14 ........ .08........ .54 ........ .!6 .!6 .52 ........ .43 ........ .22 ........ .36 ........ 2.8 -
.06 - ........ .05 ........ .01 .005 .02 .29 .01 .01 .02 .01 .01 .01 1.5 .02 .02 .16 ........ .03 ................ .34 ........ .04 ........ 3.2 ................ .03 - ... .27 .68 4.6 2.0 .!6
turewater(°0
25.0 -24.5 -25.0 -25.5 -25.0 -25.0 -26.0 -23.0 -25.0 -25.0 -25.0 -26.0 -27.0 -25.0 -
25.0 -26.0 -27.0 -25.0 -25.0 -25.526.526.0 -26.0 -26.0 -24.5 -28.0 -25.0 -29.5 -25.5 -25.0 -27.0 -25.5 -25.5 -25.5 -25.0 -25.5 -25.0 -25.5 -26.0 -25.5 -25.5 -25.5 -
Temperatureai r(°0
28.0
29.0 26.5 29.0 27.0 28.5 25.0 28.0 26.0
27.0 28.0 28.5 26.0 28.0 26.5. 30.5 29.0 28.0 28.0 29.5 32.0 29.0 29.0 29.0 26.5 30.0 27.5 32.0 27.0 26.0 31.0 28.0 27.0 28.0 27.5 27.0 28.0 25.5 27.5
27.0 27.0 27.0
168
Table 71. Water and air temperatures and instantaneous discharge
Date
Aug. 21, 1979 Sept. 5, 1979 Orfr C, 1Q7Q _ _ ,Ut L . J , <J/J
Vsi»L. ^" J * J 1 J
Dec. 28, 1979 Feb. 1, 1980 June 4, 1980 June 30, 1980 July 24, 1980 July 31, 1980 Sept. 2, 1980 Sept. 17, 1980 -- Nov. 5, 1980
at Peemgoy
Time
- 1235 -
1130 1000 - 0955 -
0955 - 1225 1000 - 0845 1145 1000 - 1000
(Pemgoy) Stream,
1 nstanta- neous
discharge
(ft3 /s)
0.11 e/.01
Oft
-- - .05 - .03 e/.Ol
02 . V f.
.30 12 --
1 -L
- .05
.27 -no _..-_
Yap Continued
Tempera ture water
oc'c
)(. r---- Zoo ---- 25.5 - _ _ oc n _ _ -
oc oI-? . U
25.5 o£ n---- Zb.U ----
-_-- oc 0 - ---I. J . U
25.0 oc c __ _ _f-J . J >£ c- 2b.5IT n---- 27.0 -
Tempera ture ai r
oft om . uOQ noft n
-- ?7 n*>T n-- Z/ .U
oA C
0*7 n-- 31 n
j 1 . U
i£. n-- Zb.U
e/ Estimated.
169
Table 72. Water and air temperatures and instantaneous discharge _ i _ _ \ V* . _ ~~~~" w _ _
Date
Oct. 8, 1969 Oct. 27, 1969 Nov. 18, 1969 -----Dec. 30, 1969 Jan. 22, 1970 Oct. 15, 1970 Oct. 28, 1970 Nov. 10, 1970 Nov. 2**, 1970 Dec. 17, 1970 Dec. 19, 1970 Jan. 27, 1971 Feb. 12, 1971 Feb. 26, 1971 Mar. 26, 1971 May 11, 1971 Mar. 2k, 1972 June 16, 1972 Aug. 11, 1972 Sept. 20, 1972 Oct. 13, 1972 Oct. 17, 1972 Nov. 10, 1972 Aug. 3, 1973Sept. 21, 1973 -July 11, 1974 July 30, 1974 Sept. 11, 1974 -Oct. 10, 197 2* Nov. 7, 1974 Dec. 12, 1974 Dec. 31, 1974 Jan. I**, 1975 June 17, 1975 July 14, 1975 Aug. 14, 1975 Aug. 28, 1975 Sept. 22, 1975 Oct. 9, 1975 Dec. 4, 1975 ~Dec. 23, 1975 Jan. 27, 1976 Feb. 3, 1976 Apr. 2, 1976
at
Time
1345 0930 0920 0935 1010 0940 1425 1520 1415 1200 1115 1055 1115 1505 1620 1215 1325 1025 1340 1245 1500 1000 1130 1425 1610 1626 1138 1502 1510 1528 1440 1232 - 0857 1410 1410 0850 1420 1525 0940- 1435 1125 1415 0935 1225
Taalgum (Talagu)
1 nstantaneous
di scharge
(ft 3 /s)
0.05 -- .!6 ........ .33 .._. ... .03 - 1.5 - .1,0 .. .02 .. .82 - .!8 - .53 -
.04 - .01 .11 .04 --........ .03 - .02 .08 «........ .07 -........ .05 - .03 - .02 .01 ... .n, .......... . 29 .. 1.2 .13 .. .29 - .02 -- .48 .. . .09 -........ .39 .. .40 -- .02 ... .29 - 1.1 ........ .37 ..
.08 -- .20 ........ .07 - .21 _. .08 - .!i, .. .... .06 «........ .08 --
Stream, Yap
Temperaturewater(°0
25.5 25.5 25.5 25.0 25.0 25.0 26.0 26.0 26.0 26.0 27.0 25.0 25.0 25.0 27.0 26.0 25.0 25.0 25.0 25.0 25.0 25.0 27.0 26.0 26.0 25.5 25.5
. 25.5 26.0 - 26.0 25.5 25.0 25.5 26.0 - 27.0 25.0 26.0 - 27.0 25.0 -
. 26.0 25.0
. 25.0 25.0 25.0
Temperatureai r(°0
- 25.0
- 00.0- 28.5 - 28.0- 30.0- 29.0- 28.5- 29.5- 29.0- 29.0- 29.0- 27.0- 30.0- 30.0- 27.0- 28.0- 28.0- 27.0- 27.0- 26.0
170
Table 72. Water and air temperatures and instantaneous discharge
Date
Mav ?0 1976 -- i ia y ^u , j 1 *»
June 16, 1976 July 27, 1976 Aug. 11, 1976 Sept. 17, 1976 Nov. 2, 1976 Dec. 3, 1976 Dec. 30, 1976 Jan. 21, 1977 Aug. 16, 1977 Sept. 28, 1977 S^nt 29 1977 -- jcp L . z.;7 , i j / I Nov 7 1977 ----.I1UV . J , ' J / 1
Nov. 30, 1977 Dec. 16, 1977 Mav 26 1978 ----.1 l<3 Y _-, w y * .7 / ^
Sept. 19, 1978 Sept. 29, 1978 Oct. 31, 1978 Nov 15 1978 ---11 W ' -< J 17 / ̂
Dpr 17 1978 -uei~ . I j , i y i u
Mar. 16, 1979 June 13, 1979 June 29, 1979 July 11, 1979 - July 26, 1979 Aug. 8, 1979 -Aug. 21, 1979 Oct. 5, 1979 Her 9ft. 1Q7Q _.
at Taalgum
Time
1220 - - 1515 -
1200 1015 1320 1045 - 1310 - 1310 1415 1100 1030 1030 1550 -- 1020 0950 --__ __ _ 1 C 1 C _ -- \5 \5 1130 - 1015 - 1040
1 7 1 C____ Uli>
0955 - 1520 - 1100 1000 1210 - 1350 -- 1315 - 1050 ___ _ noon
(Talagu) Stream,
Instanta neous
discharge
(ft 3 /s)
0.13 8 0
- .24 -______ 97 ____
.12 .15
o£------ .10 .15 ______ .89 --- .03 .02 .01 .01 - .13 .11 ______ (]Q ____pU y .06 ______ .03 ------- .13 1.2 ______ 09 ____
\J £-
______ .23 -__---_ 79 ____ / *-_ !. 3 -__ ______ .63 -
]L 1 ~
.06 ______ .03______ ri7 __
Yap--Cont inued
Tempera ture water(°c)
o/r n
____ 97 C ______O 5 9C n ___-£-J . w
27.0 -9£ C
____ 9/1 n ______9c c _ ____f-J J
25.5 -o£. n
27.0 27.0 ____ 91: c _ ____*-j j
)(. r\
o£. n 25.5 - - 25.0 ____ 9C c ____ _*-s J - 25-5 - -
o/i n
____ 9C n ______t-J . U )(. no£. n
25.0 ____ 9^ ^ ------t-j j- 25.5
r\f f\
)(. n
____ oc n ______
Tempera ture ai r(°0
0-7 n
nr n
1C. C'-- ZD.5
0-7 rZ/.i>oO r-- zo.^oQ r-- 2o.;>
25.5oo n
o^. coO r-- Zo.^
29.0-- 29.0
oft nOQ r-- Z^.i> 0-7 no/: n )(. n97 CZ/ o
_ 97 C-- z/o 30.5
o£ c
__ 9C C- ^;>o __ 97 n
oft no£ no/l r-- 26.5
27.0 79 n
31.0 9A n
171
Table 73- Water temperature and instantaneous dischargeat Mabuuq (Mabu) Stream, Ya"p
Date Time
! nstantaneous
di scharge
(ft3/s)
Tempera ture water
Sept Oct. Nov. Nov. Jan. July Sept Oct. Oct. Nov. Nov. Dec. Jan. Jan. Apr. June Aug. Sept
18, 1969 8, 1969 - 4, 1969 -20. 1969 21. 1970 - 14, 1970
, 24, 1970 7, 1970 - 29, 1970 - 13, 1970 27, 1970 22, 1970 6, 1971 - 14, 1972 - 21, 1972 16, 1972 - 11, 1972
, 20, 1972
111016100835100509461115102511001110132010301530110015501535160015101730
.37
.11
.42
.03
.6
.12
.16
.60
.18
.07
.08
.01
.51
.16
25
25
25
25
25
26
25
2526
172
Table Ik. Water and air temperatures and instantaneous discharge
Date
Sept. 18, 1969 Oct. 16, 1969 Oct. 30, 1969 Nov. 13, 1969 Dec. 18, 1969 Jan. 21, 1970 Feb. 3, 1970 -May 11, 1970 July 13, 1970 Oct. 2, 1970 Oct. 12, 1970 Oct. 27, 1970 Nov. 9, 1970 Nov. 23, 1970 Dec. 16, 1970 Dec. 28, 1970 Jan. 11, 1971 Jan. 26, 1971 Feb. 8, 1971 Feb. 25, 1971 Mar. 25, 1971 Apr. 28, 1971 May 26, 1971 Dec. 4, 1971 Jan. 14, 1972 Mar. 23, 1972Apr. 21, 1972 June 15, 1972 July 16, 1972 Aug. 10, 1972 Sept. 19, 1972 Oct. 12, 1972 Oct. 16, 1972 Nov. 9, 1972 Dec. 22, 1972 June 20, 1973 July 2, 1973 Aug. 1, 1973Aug. 15, 1973Sept. 19, 1973Oct. 5, 1973 - --Nov. 1, 1973Nov. 19, 1973 Dec. 28, 1973
Time
1020 - 1310 - 1045 - 1310 - - 0915 - 1125 - 1010 - 1110 - - 1305 - 1600 - 1000 - 0920 - 1315 - 1100 - - 0955 - 1625 - 1020 - - 1135 - - 1530 - 1610 -- 1505 - - 0955 - 1405 - - 1745 - - 0935 - 1830 - 1040 - 1250 - 1125 - - 1345 - 1245 - 1230 - 1630 - 1625 - 1525 - 1100 - 1510 - 0920 - 1400 - 1410 - 1025 - - 1355 - 1025 - 1500 -
at Burong Stream,
I nstanta-neous
discharge
(ft3 /s)
. o.lO
. .06 - .28 -. .04 - .09 . .64 .. .06 . .63 -. .04 - .26 - ----- 1.3 .10 -. .89 -. ___ L4 ____.. .48 -. .04 -- .33. .09 . 1.0 -- .97.____ .T4 __ - - .31. .49 .. .06 -.______. .09 .20 - .02 - .09 - . .02 .__.____ 1.9 __._.. .44 .. .04 -- .63 -________ .T8. .01 - .12 -.-___ .70.____ .35 -__._______ .03_______ .67
. .66 -.15
- 5.9 .11 -
Yap
Temperaturewater(°0
25.5- 26.0 - 25.5 - 25.5- 25.0- 25.0- 26.0- - 26.0- 26.0- 26.0- 26.0- 25.0- 25.0- 26.0- 26.0- 26.0- 25.0- 25.0- 25.0- 27.0- 26.0- 25.0- 26.0- 26.0- 24.0 25.0 25.0 25.0- 25.0 25.0 25.0- 25.0 26.0. 26.0 - 28.0 27.0 25.0- 26.0 28.0 27.0 26.0 27.0- 26.0 26.0
Temperatureai r(°c)
23.0
173
Table 74. Water and air temperatures and instantaneous discharge
Date
July 11, 1974 Sept. 21, 1974 Oct. 7, 1974 Nov. 5, 1974 Dec. 3, 1974 Dec. 30, 1974 Jan. 14, 1975 May 20, 1975 June 16, 1975 July 8, 1975 Aug. 25, 1975 Sept. 18, 1975 Oct. 7, 1975 ------Nov. 5, 1975 Dec. 3, 1975 Dec. 22, 1975 Jan. 9, 1976 Jan. 27, 1976 Feb. 3, 1976 Apr. 1, 1976 May 3, 1976 - May 19, 1976 June 15, 1976 July 6, 1976 July 26, 1976 Aug. 10, 1976 Aug. 26, 1976 Sept. 16, 1976 Nov. 2, 1976 Dec. 2, 1976 Dec. 29, 1976 Jan. 20, 1977 June 30, 1977 Aug. 9, 1977 Sept. 26, 1977 Sept. 29, 1977 Nov. 16, 1977 Nov. 30, 1977 Dec. 14, 1977 Dec. 30, 1977 - -Jan. 12, 1978 Feb. 1, 1978 June 28, 1978 Aug. 30, 1978
at Burong
Time
1028 1510 1410 1508 1015 1514 1555 1345 - 1435 1320 1010 1402 1230 1110 1337 1050 0940 1115 1502 1330 1230 1410 .... 1330.... 1250 .... 1135 1450 1300 1120 1120 1100 1345 1240 1430 .... 1530 1600 1630 1515 1030 1330 1345 - 1020 1130 1055 1110
Stream, Yap--Cont inued
1 nstantaneous
di scharge
(ft 3 /s)
0.50 .. .24 -.. 1.3 ... 8.5 ----- .03 ------ .43 -
.05 .32 -
.22
.91 -
.40 -.. 2.4 ..... 1.2 .07 -- .36 ------ .87 -_. .06 - .33 -----
.14 - .98 -
.06 - .43 - .29
.06 .62 - .27 .. .84 .57
.11
.29 -- 1.2 .. .16
.06
.09
.16 - .32
.01
.10 -- 2.1
.01
.01
.03 -
.14
.08
Temperaturewater(°c)
... 25.5 27.0 - 26.0 -... 25.5 - 25.0 - 26.5 - 26.0 - 27.0 - 27.0 - 26.0 - 26.0 - 26.0 - 26.0 - 26.0 - 29.0 - 24.0 - 25.0 - 26.0 - 26.0 -... 26.5 - 26.0 -... 26.5 ----- 26.0 - 28.0 - 25.5 - 25.5 - 26.0 - 26.0 - 25.0 - 23.0 - 26.0 - 26.0 - 28.0 - 28.0 - 26.0 - 27.0 - 27.5 -... 26.5 « 27.0 - 28.0 - 26.0 - 27.0 -... 25.5 -... 26.5 -
Temperatureai r(°0
- 32.5- 28.5 29.0- 28.5- 29.5- 30.0- 30.0- 28.0- 29.0 28.0- 32.0- 30.0- 28.0- 32.0- 27.0- 28.0 29.0 - 27.5- 32.0- 29.0- 30.0 29.0 - 34.5 28.0 27.0- 28.5 28.0 26.0 25.0 29.0 28.5 - 31.5 30.0 29.0 29.0 - 31.5 30.0 30.0 30.5 28.5 29.0 28.5 31.0
174
Table 74. Water and air temperatures and instantaneous discharge
Date
Sept. 15, 1978 Sept. 29, 1978 Oct. 26, 1978 Nov. 9, 1978 Nov. 28, 1978 Dec. 12, 1978 Dec. 27, 1978 Mar 15 1Q79 ---i ia i . i j , i 3i jMay 15, 1979 limo 19 1Q7Q _____
lnn<a 97 1Q7Q _____
July 11, 1979 July 30, 1979 Ann Q 1 Q7Q _Mug. y, iy/y --- -Ann 91 1Q7Q _____Hug. zi, ly/;? Sf»nt 5 1P7P -----OCfJ L . p , *J 1 J
^or»t- 9fJ 1Q7Q ____oept. zu , ly/yOct. 10, 1979 Oct. 30, 1979 Dor 97 1Q7Q _____U6C. LI , I;?/"Mar. 26, 1980 May 20, 1980 June 3, 1980 June 30, 1980 July 23, 1980 July 30, 1980 Ann ?n iQftn --_
at Burong
Time
1445 1440 1050 0910 1320 1030 1340 1055 1015 1340 1045 _ 1350 1040 1200 1235 1200 1235 1520 1520 _ 1135 - 1010 ____ I44c. _ ____ ____ | <^*f p ________
1050
0905
0925 1345 ____ i7in ____
Stream, Yap Continued
I nstanta neous
di scharge
(ft 3 /s)
- 1.5 .- .17 .
.11 __ 2.9 -
.06 -_. 1.0 - .04 -
.21 .61 -- 2.5 - __ 1.2 - 2.4 -
.12 - 3.6 -----
.21
.02 __ .07 -
1 ft.10
- .07 - .04 Q7 _____. u j
.06 44 __ _. ~T
- .42 1Q _____ i j
9 1 ___
Tempera ture water(°0
O£. C--- zb.5 -- ofi c2o.5 -- )L no£ no£ c___ 2b.i> ----- o£ n9A C
25.0 -
___ 9C c ____.t-j j f\f. no£ c--- 26.5 ----- 9c c ____.t-j j oc c--- 25.5 -- o£ c - 2b.5 -
___ 27 0 ---£. / . U
o~7 n
25.0 - o£ n--- Zb.U -----or r--- o o -----
27.5 -
25.5 -- o£ n
27.0 - ___ oc n __.
Tempera ture ai r(°0
9Q C---- ^yo- 30.5
oQ r- 28.5 oft c---- 20.5
- 30.0- 27.5- 30.5 - 24.0
oft c-- 20.5 oft noft n
- 32.0oft n --- 2o.U
- 27.0 i o n
- 30.0- 30.0
)(. r\
27.5- 32.0
oft c---- 2o.5 - 35.0
oft c- - 2o.5 - 27.5
oft r- 20.5- 32.0 .___ 97 n
175
Table 75- Water and air temperatures and instantaneous dischargeat Monguch Stream, Gagil -Tamil
Sept Oct. Mar. Apr. Apr. May July
Date
. 16, 1980 20, 1980 -----24, 1981 -----7, 1981 97 IQftl _____
14, 1981 ------
99 1Q.R1 -----
Time
1MQ _ . 1210
1 "3 "3 C- - 1335 1250 1300 1150 1040
I nstanta neous
di scharge'(ft 3 /s)
- 1.3 -. .44 -. .16 -
nft----- .DO ----- o£----- .2b ---
- .12 - 1.6 -
Tempera ture water(°C)
i D n--- Zo.U ----- o£ n07 r --- 2/0 --
,___ 90 n _ __.t. J . U
0"7 C--- LI .5 ----- oo n0"7 C --- LI .5 --
Tempera ture ai r(°0
- 29.0 oft c---- Zoo
.__- 98 5tW . J
- 30.5o Q n --- 20. U iQ c---- Zoo
.__- 70 c;JV J
Table 76. Water and air temperatures and instantaneous dischargeat Mukong Stream, Gagil -Tamil
Date
Mar 97 1Q79 -----i la I £~j* \ j j £~
Apr. 21, 1972 -May 18, 1972 -June 16, 1972 -July 15, 1972 -Aug. 10, 1972 - Oct 12 1972 ---\X V,* U 1 __ } \ ij I £~
Oct. 16, 1972 -T\ar 1Q 1 Q7 9 ____.
lan Q 1 Q7 7 ______
Jan. 29, 1973 -Feb. 16, 1973 -Feb. 26, 1973 -May 7, 1973 -July 2, 1973 -Aug. 15, 1973 -Aiin 9Q 1Q"77 _____
Dor k 1Q77 -- _ --U6C. H, II7/.5
Mar. 7, 1974July 10, 1974 -Aiin 1A 1Q7/1 _____
Drt 7 1Q7/I __
Instanta- Tempera- neous ture
discharge water
Time (ft3 /s) (°C)
64
1035 - 1450
no ofl 1147 1110 1520 . 1530 1100 1005 1100 1410 . 1350 1020 1050 1045 1100 . 1550
1^7 1555 ._ _ lAnc ________
3.3 1.7 -
1 9 ________
1 9 ________
3.61.1 1 9 ________
1.1 oft
.21
.06
.12 i 0
3.7 -7Q ________
1.2 1.1
3.0 2.2
7 1
26.0 25.0 25.0 26.0 26.0 25.0 26.027.0 oft n26.0 26.0 26.0 26.0 27.0 25.0 28.0 27.0 28.0 28.0 26.597 C ____.Z/ O -----
9A C
97 n __.
Tempera ture ai r
- 30.0
30.0oQ n.__- 20.0
71 0
176
Table 76. Water and air temperatures and instantaneous dischargeat Mukong Stream, Gagi 1 -Tami 1--
Date
Apr. 1, 1975 ------Apr. 2, 1975 -----Apr. 16, 1975Apr. 30, 1975 -----May 20, 1975 -----June 18, 1975 July 8, 1975July 28, 1975 -----Aug. 6, 1975 -----Aug. 14, 1975 ~ Aug. 27, 1975 - Sept. 18, 1975 -Oct. 7, 1975 -----Nov. 5, 1975 -----Dec. 3, 1975 -----Dec. 22, 1975 Jan. 8, 1976 Jan. 27, 1976 Feb. 3, 1976 -----Feb. 18, 1976 Mar. 3, 1976 -----Mar. 12, 1976 Apr. 1, 1976 Apr. 15, 1976 -----May 3, 1976 -----May 19, 1976June 15, 1976 July 7, 1976 -----July 26, 1976 Aug. 9, 1976 -----Aug. 26, 1976 Sept. 16, 1976 Oct. 10, 1976 Nov. 2, 1976 Dec. 2, 1976 Dec. 29, 1976 Jan. 20, 1977 Feb. 3, 1977Mar. 10, 1977 Mar. 22, 1977 June 30, 1977 Aug. 10, 1977 - Sept. 29, 1977 Nov. 1, 1977 -----
Time
- 1530 1350- 0955 1030 - 0945 1425 1025-- 1020 - 0945 - 1552 1045 1010 0940- - 0945 1000 - 0915 1415 - 0935 1335 1410 - 0935 0920 1100 1030 1120 - 1020 1030 1010 1030 1430 1130 - 0950 0845 1015 1000 1040 - 1115 - 0945 1040 1010 1110 1420 1520 - 0930
I nstantaneous
di scharge
(ft 3 /s)
0.17 - .17 -----________ .03 -----________ 1^ ________________ 4.7 ________ 11 ________ 3.1 ________________ .89________ 3.0________ 3.2________ 1.4 ________________ 6.9________ 3.9 ________________ .86 - ________ 2.9________ 3.6 ________________ .77 ________________ 1.9 ________________ 1.4 _______________ .45 ________________ .33 ________________ .31 ________________ 2.4________ .67________ .80 ________ 4.8________ L5 ________________ 1.8________ 2.0 ________ 4.0 _ - _____ 3.5 ________________ 3.5 ________________ .71 ________________ .77 ________ 2.0 ________ 2.3________ .60 _______ .80 - .24 ----- - .17________ L6________ 1.2 1.1 _______ .59 ________
-Cont inued
Temperaturewater(°0
28.0 -28.0 -26.0 -26.0 -27.0 -27.0 -26.0 -26.0 -26.0 -27.0 -26.0 -26.0 -26.0 -26.0 -25.0 -25.0 -25.0 -25.0 -26.0 -27.0 -26.0 -26.0 -25.5 -----26.0 -27.0 -26.0 -27.0 -26.0 -26.0 -27.0 -26.0 -25.5 ~26.5 -26.0 -23.0 -26.0 -26.5 -27.5 -----26.0 -26.0 -27.0 -28.0 -26.0 -26.0 -
Temperatureai r(°0
- 31.0-- 32.0- 28.0- 28.0 29.5- 29.0- 28.0- 29.0 29.0 32.0 28.0 29.0 27.0 29.0 27.0 27.0 29.0 26.0 - 27.5 - 33.0- 28.5 28.0 28.0 28.0 32.0 28.5 29.0 28.0 -- 29.5 30.0- 27.0 28.0- 28.0 - 27.5 25.0 27.0 29.0- 29.0 30.0 29.0 29.0 30.0 30.0 29.5
177
Table 76. Water and air temperatures and instantaneous discharge
Date
Nov. 16, 1977 -Nov. 29, 1977 -Dec. 15, 1977 -Dec. 29, 1977 -Jan. 12, 1978 -Feb. 1, 1978 Feb. 23, 1978 -Mar. 15, 1978 -Mar. 30, 1978 -Apr. 12, 1978 -Apr. 18, 1978 -May 4, 1978 -Hay 25, 1978 June 15, 1978 -June 28, 1978 -July 21, 1978 - Aug. 30, 1978 -Sept. 15, 1978 -Sept. 29, 1978 -Oct. 26, 1978 -Nov. 8, 1978 Nov. 28, 1978 -Dec. 12, 1978 -Dec. 27, 1978 -Jan. 12, 1979 -Jan. 31, 1979 -Feb. 13, 1979 -Feb. 27, 1979 -Mar. 15, 1979 -Mar. 30, 1979 -Apr. 7, 1979 ---Apr. 25, 1979 -May 17, 1979 May 31, 1979 June 14, 1979 -June 29, 1979 -July 13, 197S --July 30, 1979 -Aug. 9, 1979 -- Aug. 22 , 1979 -Sept. 6, 1379 -Sept. 20, 1973 Oct., 10, 1379 -Oct. 31, 1379 -
at Mukong
Time
- 1415 - 0950 --- 0940 - 0925 ~« 0915 -. 0940 . 0945 ~. 1500 . 1400 --. 0940 --- 1640 - 1010 .... . 1355 ... 0940 - 0950 . 1000 . 1000 . 1005 1345 -. 1000 . 0940 ........ 0930 --. 0920 .... . 0930 --. i4io .......... 0935 .. .. 0930 -........ 1355 .......... 0855 --........ 1535 ~........ 1355 ... 0900 - 1710 . 1620 . 1400 . 1420 ~ 0925 --- 0910 . 1025 - 0915 .. i4io --........ 1135 ... i4i5 ~ 1030
Stream, Gagi 1 -Tami
1 nstanta-neous
di scharge
(ft3/s)
0.69 ...... .82 ~...... 3.9 ........... .58 ........... .65 -----...... .67 ----- .46 ..... .32 - - .18 ..... .10 ........... .58 ..... .11 ...... .19 ........ .32 ..... .80 ...... .86 -----.. 2.4 6.1 1.6------ 1.2 ...... .98 ..... 1.1 ... 2.4------ l.l ...... .48 -----...... .37 ..... .22 .20 1.0 ...... .18 - ...... .09...... .13 ........... .18. .. .15 ........... 1.7 . ... 3.7 2.2 1.1 -.. 6.2 1.6 .90 1.2 1.5 1.3 --
1 Cont inued
Temperaturewater(°0
28.0 26.0 26.0 26.0 25.0 26.0 27.0 28.0 27.0 26.0 28.0 27.5 27.5 26.5 27.0 26.0 26.5 26.0 29.0 27.0 26.0 25.5 26.0 25.0 26.5 ... 25.5 25.5 - 27.0 26.0 28.0 27.5 26.5 27.0 28.5 27.0 28.0 26.0
25.5 - 26.0 28.0 26.5 26.0 27.5
Temperatureai r(°c)
34.0 30.0 28.0 27.5 27.0 28.0 29.0 31.0 32.5 28.0 32.0 28.0 31.0 28.5 28.5 29.0 28.5 26.5 32.0 27.5 29.5 28.5 28.0 28.0 31.0 28.0 27.5 32.0 28.0 32.5 31.0 29.0 33.0 35.5 30.0 30.0 32.0 28.0 27.5 29.0 34.5 33.0 27.0 28.5
178
Table 76. Water and air temperatures and instantaneous discharge
Date
Nov. 19, 1979 -Dec. 5, 1979 -Dec. 27, 1979 -Jan. 22, 1980 Feb. 1, 1980 - Feb. 23, 1980 Mar. 12, 1980 Mar. 28, 1980 Apr. 11, 1980 Apr. 23, 1980 May 16, 1980 June 3, 1980 June 19, 1980 July 24, 1980 July 31, 1980 Aug. 30, 1980 Sept. 16, 1980 M L. iqftn _--
at Mukong
Time
1410 1010 1040
1420 1510
1 O 1 C
0955 - 1110 0905 --...... 0930 -- 1430 0920 1015 1305 -- 1430 1130 -- -- 0930 --
, ___ niin
Stream, Gagil-Tami
1 nstanta- neous
di scharge
(ft3/s)
0.60 -...... .56 ......
qq __ _ _. jj----- - .51 _ __ 39 - . jf-
1 ft------ l.o 24 ------. ^ i
rQ .58 - .57 ______ kf> __ _ .
» w
1 9 _ ___ .1 . £m
ft? .83 .______ C9 __ _.oz ---- 1.5 -______ i 7 _______ /...... 7.1 ......._ -__ 9 q _ .f- ./ ____ cn ___.
1 Cont inued
Tempera ture water(°0
oft n.__ ZO.U ------ r\c. n
OT n.__ //.U -- --
o"? n.__ //.U ----- oft n.__ ZO.U ---. o c r 25.5
>£, c
o £ no£ r--- 20.5 ------oA c
O"7 C- //o o"7 nO"7 C -- //.5 -oft no c no£ nr\f n.__ 2o.U ------
.__ 97 C _.
Tempera ture ai r(°c)
33.0 ___ 29 5* j j 30.0 32.5
oft no£ c--- zoooQ r--- Zoo
29.5 30.0 30.0 31.0 30.5 32.5 32.0- 31.0 27.0
oft n 9Q n
179
Table 77- Water and air temperatures and instantaneous dischargeat Gilaew (Bileiy) Spring, Gag M -Tamil
Instanta- Tempera- Tempera- neous ture ture
discharge water air
Date
July 30,Oct. 15,Oct. 30,Nov. 12,Nov. 25,Dec. 18,Jan. 14,Jan. 22,Feb. 3,Feb. 19,Mar. 10,July 13,Oct. 3,Oct. 12,Oct. 22,Nov. 9,Nov. 23,Dec. 16,Dec. 28,Jan. 6,Jan. 26,Feb. 8,Feb. 25,Mar. 23,Apr. 22,May 26,Mar. 23,Apr. 20,May 18,June 16,July 15,Aug. 10,Sept. 18Oct. 12,Oct. 16,Nov. 9,Dec. 19,Jan. 9,Jan. 29,Oct. 3,Dec. 28,Mar. 7,July 10,July 29,
1969 --1969 1969 1969 1969 1969 1970 1970 --
1970 1970 1970 -----1970
1970 1970 1970
1970 1970 1970 1970
1971 1971 -
1971 1971 1971 1971
1971 1972 1972
1972 1972 1972 1972
, 1972 1972 -1972
1972 1972
1973 1973
1973 1973
1974 -19741974 -
Time (ftvs) (°C) (°C)
- 1350 1005 0900 0910 _ _ 1345 1405 0925 1445 0900 1020 0915 1510 1425 1430 1105 1045 1400 1115 1320 1515 1010 1630 1405 1515 1015 1050 1515 1430 0850 - 1305 - 1405 1015 1025 0940 1410 1400 1415 0926 0905 1005 1005 1508 1450 1355
0.80 .12 .11 .19 -.19 .11 .10 .07 .05 .03 .........02 .08 .18 .37 .........17 .11 .25 .09.06 .02 .10 .05 -----.08 .14 -.05 -.30 .18 .06 .03 .........02 .07 . ..25 .81 -- .20 .11 .04 .03.02 .01 .31 .10 .01 .11 .24
26.026.026.026.026.028.026.026.026.026.027.027.028.026.027.026.027.027.027.027.026.026.027.027.027.025.026.028.025.029.028.025.026.026.027.029.0 27.028.0 31.026.026.026.026.027.527.026.0
180
Table 77.
Date
Aug. 16,Sept. 12,Oct. 3, 1Nov. 9, 1Apr. 30,July 8, 1Aug. 27,Oct. 7, 1Dec. 3, 1Jan. 8, 1Apr. 1, 1May 19, 1Aug. 9, 1Oct. 10, Dpr 2 1L/ d» -L j 1
Jan. 20,Nov. 29,uet . z.7 ,Feb. 1, 1I id f i j
Apr. 12,Aug. 30, Oct. 26,Nov. 28,Dec. 27, Sept. 16,fin- on
at Gi laew (Bi leh
Time
1974 1512 1974 1506
974 1525
1Q7C _____ _ __ 113C _____ y/:> i'.?;? -----975 1100
975 10 55 975 no5 976 1550 976 1230 976 1150 976 1545 1976 0950 976 0915
1Q77 1inS1Q77 ~
978 1040 1978 1435 1978 - - 0855 1978 0855 1978 0850 1978 1035 1980 0905 1980 1130
iQftn __- imn
f) Spring, Gagil-Tamil Continued
Instanta- Tempera- Tempera- neous ture ture
discharge water air
(ft 3 /s) (°C) (°C)
0.45 27.0 31.5.06 27.0 29.5
.05 25.5 32.0.45 26.0 29.0.10 26.0 31.0
1 Q o£ n oo n .16 30.0 3^.0
.10 27.0 35.0
.04 26.0 29.0nfl oVi n oft n
.42 27.0 30.0r\f\ i£ n oQ n--- .oy -------- zo.u ----- - zo.un-7 07 n OQ C
on olic o£c_._ n7 __ ____ 07 n ________ OQ n
.01 29.0 30.5
.03 26.5 30.5
.03 27.0 30.0 ___ no _______ OQ n ________ 79 n
ni i£. n oQn--- .01 ----- - Zo.U -------- zo.U n o o£ n 07 cno o£ n 07 n.02 26.0 30.0
1 ft oc n 97 n.40 27.0 28.001 _____ 07 n __ _ 9Q n
181
Table 78. Water and air temperatures and instantaneous discharge
Date
Sept. 19, 1969 Nov. 6, 1969 Nov. 18, 1969 Jan. 14, 1970 Jan. 29, 1970 Sept. 15, 1970 Sept. 29, 1970 Oct. 5, 1970 Oct. 30, 1970 Nov. 12, 1970 Nov. 25, 1970 Dec. 28, 1970 Jan. 6, 1971 Mar. 23, 1972 Apr. 21, 1972 May 18, 1972 June 16, 1972 July 15, 1972 Aug. 10, 1972 Sept. 18, 1972 Oct. 12, 1972 Jan. 9, 1973 -July 10, 1974 Aug. 16, 1974 Sept. 12, 1974 Oct. 3, 1974 Nov. 9, 1974 Dec. 3, 1974 Jan. 2, 1975 Apr. 30, 1975 May 20, 1975 July 8, 1975 Aug. 27, 1975 Oct. 7, 1975 Dec. 3, 1975 Feb. 18, 1976 Apr. 15, 1976 May 19, 1976 July 7, 1976 Aug. 9, 1976 Oct. 10, 1976 Dec. 2, 1976 Jan. 20, 1977 Nov. 29, 1977
at Gil
Time
1420 0940 1340 1023 0945 1100 1055 1100 0930 1400 0955 1455 1400 1600 0840 0950 1320 1445 1103 1125 1025 1015 1346 1426 1410 - 1439 1543 1348 1413 1150 1045 1150 1140 1020 1030 1450 1210 - 1115 1045 1510 0930 - 0835 1030 1030
aew (Bi leiy) Strear
1 nstantaneous
discharge
(ft 3 /s)
0.46 .88
.32 ... .24 .20 .15 .19 .35 ........ .38 ........ .45 ........... .54 ... .. .]4 . . 15 . .42 .10 .06 .08 -- .13 ...
.48 2.0 .39 .04 .. .46 ... 1.2 ........ .27 ... .32 1.4 ........ .67 ... .40 .29 ........... .19 ... . .81 ... .36 ...
.64 .20 .10 .11 - 1.7 ... .42 ... .71 ... .4! .26 .10 - .13 ...
n, Gagi 1 -Tami 1
Temperaturewater(°0
82.0 78.0 78.0 26.0 26.0 80.0 78.0 27.0 26.0 27.0 26.0 26.0 26.0 26.0 25.0 25.0 26.0 27.0 25.0 26.0 26.0 26.0 27.0----- 27.5 - 28.0 - 27.0 - 27.0 28.0 - 28.0 26.0 - 28.0 - 25.0 - 26.0 - 27.0 - 27.0 28.0 - 28.0 27.0 - 27.0 - 27.0 27.0 25.0 - 26.0 - 27.5 -
Temperatureai r<°0
- 30.5 33.5- 31.5- 31.0 - 35.0- 32.0- 29.0- 32.0- 27.0- 30.0- 30.0- 29.0 - 32.5- 30.0- 29.0- 29.0 - 23.5- 29.0- 26.0- 29.0- 32.5
182
Table 78.
Date
Dec. Feb. Mar. Apr. June July Aug. Oct. Nov. Dec. Dec.
29, 1, 15, 12, 8, 21, 30, 26, 28, 27, 27,
1Q77 -I jl 11978 --1978 -1978 -
1978 --1978 -1978 -1978 -1978 -1978 -1 Q7Qly/J ~
at Gi laew (Bi leiy )
Time
-1000 __ 1010 1/J20 08/iQ ________ nft9n ------
_ no i c________ u^l^ ------ nO o n
_______ nft9C - -
1010 1005 ------- 0935 -----
Stream, Gagi
1 nstanta neous
di scharge
(ft 3 /s)
0.13 - .07 -
.06 -n o
-- .05 ----- 105 ----- .11 .06 1/i _ -. ii o nOU -----1 Q. lo -----
I -Tami I --Cont inued
Tempera ture water(°c)
r\f T\
o£ n____ 9Q C ________/:?.:?- 25.0 - .___ 96 n --------
_ 9C C _- ____ --- Oo --------- 25.0 -- __ 9C C ________- O O____ 9c n ---------- ^3 . u -- - --.___ 9c n --------£*) .V
.___ 97 n --------£/ .V
Tempera ture ai r(°0
- 28.0 - 29.0 32.5 26.5 27.0 - 32.0 - 27.0 - 27.0 - 28.5 25.5 - 30.0
Table 79. Water temperature and instantaneous discharge
Oct. Nov. Sept. Oct. Oct. Nov. Nov. Dec. Jan..lan
Date
1C 1969 - j , i j^jj 6 1969 -- u , i .yuj9Q 1 Q7 fl
7, 1970 -
19 1 Q7OIz, ly/u ---
24, 1970 6, 1971 -9A 1Q71 _--.
at Yanbi
Time
0905 -
- 1025 ------ - 1755 -
------ 177C _1.5.52 -___-_ nQ9fl------ U;7ZU -
- 1530 -1 3 9 C
______ nfcic. _
lang Stream, Gagi I -Tami I
I nstanta neous
di scharge
(ft3 /s)
0.02 ______ _ 19 ________
________ .07 ----- -"
1 9
*ri9
2 1__ ____ m ________
Tempera ture water
_ 9C C- Zp . ;>
- 25.5o£ n
o Q n
77 0Z. / v-»
- 27.0 9^. n
- 27.0o£ n
9A n
183
Table 80. Water and air temperatures and instantaneous discharge
Date
Sept. 19, 1980 Oct. 20, 1980 Mar. 24, 1981 Apr. 7, 1981 -Apr. 27, 1981 May 14, 1981 July 18, 1981 Jan. 20, 1982 Feb. 9, 1982 Mar. 24, 1982 A O t f*i O *\Apr. o, 19o2 A O^ 1 /"\O OApr. 26, 19o2 ---May 7, 1982 - May 28, 1982 June 15, 1982 July 7, 1982 -Aug. 2, 1982 Aug. 18, 1982 Sept. 13, 1982 Sept. 29, 1982 f\ *- i O i/^OoOct. 1o, 19o2 Nov. 10, 1982 Nov. 24, 1982 Dec. 9, 1982
at Eyeb
Time
1140 1300 1420 1320 - 1325 1230 1010 1305 1215 - 0935 1200 1255 1020 1115 - 1455 1320 1300 1130 1230 1405 1111 1010 1120 1250
Stream, Gagi
1 nstanta neous
di scharge
(ft3 /s)
__ 1 Q ___-_' O_. L 7 ___ _^ /
20 ----. f-\>10 __ ._ ' j n/i __._
V I
-- .07 - 99 _ ___^ £-
LQ __ "./ - 1.6 -
99 _ .__^ ^
~ .31~ .19
.40 - cli ___ j~
-- .36 --- 1.3 -- 1.0
i L ___ _i . ~ ]4
QC.05 -- .77 --- .77 -
Cft.50 -- .. 2.4
1-Tami 1
Tempera ture water(°c)
o£ r---- 26.5 <)f n---- 26. U ----- oQ n*>Q n---- 2o.O -- 27 ^ -- * / *jofi r---- zo.5 ----- 9^ n^C. r---- Z6.5 ----- o^l r---- 26.5 -----
____ 2C. ^ _ -*-j j r\f n---- /b.U -----O Q IT---- 2o.5 --
---- 27 0I- 1 . w
oQ n---- Zo.U ----- ____ 27 £. -- * / *j
)-i r -- 2.1. 5 27 0 -- 1- I * V
<)C n---- Zb.U ----- o^l r26.5 ----- 26 ^ -- fcW . ^ 5/1 nZ6.U -----O^l fl---- Z6.U ----- >/! no£ r---- zo . 5 -----
Tempera ture ai r(°0
- 27.0__ 9Q C - - ^yo_ 9Q C --- zy.5
ofi n_ OQ C---- zyo
.__- 28 0^w . u oQ n---- Zo.U o^. c- - 26.5
._-- 97 c^ / j
..-- 97 cf- 1 »J
.__- 9Q C " ~ ^y«->
9Q C---- zo.5- 29.0
9fi n---- Zo.U .__- 27 ^*- 1 »j- 27.0
9Q nZO.U27 0l~ / V
97 c^ / 2 .-_- 97 n
£- / U
.__. 97 c^ / « 3
Table 81. Water and air temperatures and instantaneous dischargeat Qamin (Amin) Stream, Maap
Date Time
Instanta neous
di scharge
(ft3 /s)
Tempera ture water
Tempera ture ai r o.( uc)
Sept. 19, 1980 Oct. 20, 1980 - Mar. 24, 1981 July 18, 1981
1550 0.49 27.00950 1.2 26.01230 .03 27.01330 .28 26.5
29.029.5
184
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