4-2-1 preliminary site survey.pdf

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Workshop on Renewable EnergiesMarch 16, 2005

Majuro, Republic of the Marshall Islands

Module 4.2Module 4.2 MicroMicro --HydroHydro

4.2.1 Preliminary Site Survey4.2.1 Preliminary Site Survey

Tokyo Electric Power Co. (TEPCO)

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MicroMicro --Hydro Development FlowHydro Development Flow

Potential Site IdentificationPotential Site Identification

Preliminary Site SurveyPreliminary Site Survey

PlanningPlanning

DesigningDesigning

ImplementationImplementation

Operation and MaintenanceOperation and Maintenance


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Outline of Site Survey (Reconnaissance)Outline of Site Survey (Reconnaissance)

Objective To roughly evaluate the feasibility of the project

To get information necessary for planning

Items to be investigated Potential capacity of the project site

Measurement of river flowMeasurement of head

Topographical and geological condition of the sitesfor the structure

Accessibility to the site Power demand and distance from the load center to

the site of the power house Ability of the local people to pay for electricity Willingness of the local people for electrification

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Preparation for Site SurveyPreparation for Site SurveyInformation Gathering Prepare 1/50,000 scale maps to check the location, catchment

area, villages, access road and topography of the project sites. Gather available information on accessibility to the site, the

weather conditions, social stability, and so on. Make copies of the 1/50,000 scale maps and route maps enlarged

by 200 to 400%. Prepare checklists and interview sheets for site survey.

Planning of preliminary site survey Make a plan and schedule for site survey considering accessibility

to the sites and the weather conditions. Allow sufficient time in the schedule since most of sites are located

in remote and isolated areas


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Preparation for Site SurveyPreparation for Site Survey

Necessary Equipment for Site SurveyEquipment Equipment

Route map Altimeter

Topographic map GPS (portable) Reconnaissance schedule Camera, film

Checklist Current meter

Interview sheet Distance meter, measuring tape

Geological map Hand level

Aerial photographs Convex scale (2-3m)

Related reports Hammer

Clinometer

Field notebook Knife

Scale Scoop

Pencil Torch, flashlight

Eraser Sampling baggage

Colored pencil LabelSection paper Compass

Stopwatch

Batteries

M a p s a n

d s

h e e

t s

S t a t i o n e r y

E q u

i p m e n

t

Notes: : Necessary equipment for preliminary site survey

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Site SurveySite Survey Investigation of capacity potential

River flow measurement Head measurement

Investigation for layout and design of facilities Intake site Waterway route Powerhouse site Transmission/distribution line route

Investigation of demand forecast

Other outline surveys


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River Flow MeasurementRiver Flow Measurement

Reason for conducting the measurements: Since the catchment area of micro-hydro power is relatively

small, the river flow at micro-hydro sites is site-specific. Flow prediction using the area-proportion and area-rainfall

methods is not exactly accurate. Some rivers dry up in the dry season Without checking the actual flow, we cannot be confident of

the potential capacity of the projects . Purpose:

To get enough data to accurately predict river flow at theproject site

To check the minimum river flow in the dry season Method:

Current meter method Float method Bucket method Weir measuring method

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River Flow MeasurementRiver Flow MeasurementCurrent Meter Method1. Select the measuring point.

No irregular waves or whirlpools at the surface No backflow or stagnation No irregular changes in the water level

2. Measure the cross-section area Width Depth

0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16

0.661.15

1.31 1.41 1.67 1.77 1.80 1.84 1.80 1.57 1.44 1.28 1.180.92

1.31 1.31 1.31 1.31 1.31 1.31 1.31 1.311.31 1.31 1.31 1.31 1.31 1.31 1.31 1.31

0.82


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3. Measure flow velocity by a current meter Depth > 1.7 ft:

Two-point measuring: V m= 0.5

(V0.2 + V0.8 ) Depth < 1.7 ft:One-point measuring: V m= V0.6

where,Vm: Average velocity of the sectionV0.2 : Velocity at 20% depth below the water surfaceV0.6 : Velocity at 60% depth below the water surfaceV0.8 : Velocity at 80% depth below the water surface

Bw

d4 d5 d6

w

V0.8

V0.2

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River Flow MeasurementRiver Flow Measurement4. Calculation of the river flow

Section area: A abcde= Aabcf + A fcde= 0.5 w (d4+d5) + 0.5 w (d5+d6)= 0.5 w (d4 + 2 d5 + d6)

Average velocity: V m= 0.5 (V0.2 + V0.8 )

River flow at section: Q abcde = Aabcde Vm

Total river flow = Q

c

w

d4

wa

b

f

d

e

d6

V0.8

V0.2d5

Bw

d4 d5 d6

w

V0.8

V0.2


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Exercise: Calculation of River FlowExercise: Calculation of River Flow

Calculate the river flow using the flow data below.

BinalianResult of Discharge measurement C.A.= 10.5mile2

No. Width UnitInterval Depth Unit Area Corresponding

Area Discharge

(ft) (ft) (ft) ft 2 ft2 20%De th 80%De th Avera e f t 3/ s0 0.00 - 0.00 - - - - - -1 1.31 1.31 0.66 1.840 1.6142 2.62 1.31 1.15 - - - - -3 3.94 1.31 1.31 2.636 2.4964 5.25 1.31 1.41 - - - - -5 6.56 1.31 1.67 3.862 3.6156 7.87 1.31 1.77 - - - - -7 9.18 1.31 1.80 2.980 2.7008 10.50 1.31 1.84 - - - - -9 11.81 1.31 1.80 3.109 2.797

10 13.12 1.31 1.57 - - - - -

11 14.43 1.31 1.44 2.216 2.04412 15.74 1.31 1.28 - - - - -13 17.06 1.31 1.18 1.969 1.90414 18.37 1.31 0.92 - - - - -15 19.68 1.31 0.82 1.829 1.42016 20.99 1.31 0.00 - - - - -

Total - - - - - - -

Velocity (ft/ s)

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Exercise: Calculation of River FlowExercise: Calculation of River FlowSection area: A abcde

= Aabcf + A fcde= 0.5 w (d4+d5) + 0.5 w (d5+d6)= 0.5 w (d4 + 2 d5 + d6)

Average velocity: V m= 0.5 (V0.2 + V0.8 )River flow at section: Q abcde = Aabcde VmTotal river flow = Q c

w

d4

wa

b

f

d

e

d6

V0.8

V0.2d5

0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16

0.66

1.151.31 1.41 1.67 1.77 1.80 1.84 1.80 1.57 1.44 1.28 1.18 0.92

1.31 1.31 1.31 1.31 1.31 1.31 1.31 1.311.31 1.31 1.31 1.31 1.31 1.31 1.31 1.31

0.82


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Calculation of River Flow

BinalianResult of Discharge measurement C.A.= 10.5mile2

No. Width UnitInterval Depth Unit Area Corresponding

Area Discharge

(ft) (ft) (ft) ft 2 ft2 20%De th 80%De th Avera e ft 3/ s0 0.00 - 0.000 - - - - - -1 1.31 1.31 0.656 0.430 1.614 0.561 0.492 0.526 0.8502 2.62 1.31 1.148 1.183 - - - - -3 3.94 1.31 1.312 1.614 3.400 0.804 0.761 0.782 2.6594 5.25 1.31 1.410 1.786 - - - - -5 6.56 1.31 1.673 2.023 4.282 1.178 1.102 1.140 4.8806 7.87 1.31 1.771 2.259 - - - - -7 9.18 1.31 1.804 2.345 4.734 0.909 0.823 0.866 4.0998 10.50 1.31 1.837 2.388 - - - - -9 11.81 1.31 1.804 2.388 4.605 0.948 0.853 0.900 4.146

10 13.12 1.31 1.574 2.216 - - - - -

11 14.43 1.31 1.443 1.980 3.765 0.676 0.623 0.649 2.44512 15.74 1.31 1.279 1.786 - - - - -13 17.06 1.31 1.181 1.614 2.991 0.600 0.581 0.590 1.76614 18.37 1.31 0.918 1.377 - - - - -15 19.68 1.31 0.820 1.140 1.678 0.558 0.433 0.495 0.83116 20.99 1.31 0.000 0.538 - - - - -

Total - - - - 27.068 - - - 21.677

River Dischar e Measurement

Velocity (f t/ s)

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Electromagnetic Current Meter Propeller Current Meter

Actual Measurement


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Source: Micro-Hydro Design Manual

Float Measuring Method

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Bucket method Direct measurement with a bucket Small river flow


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Weir measuring method

Q = C

L

h1.5

C = 3.330 (1+ ) (1- )where,

Q: River flow (ft 3/s)C: River flow coefficient on experimental BasisL: Opening width of weir (ft)H: Overflow depth (ft)

In SI unitsQ = C L h1.5

C = 1.838 (1+ ) (1- )

where,Q: River flow (m 3/s)L: Opening width of weir (m)h: Overflow depth (m)

0.0039

H

10(h/L) 1/2

(H/L)1/2

100.0012

h

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Head MeasurementHead MeasurementWater -filled tube method

Useful for low head Easy to handle No need for a skilled engineer Relatively accurate

H1

H3

H4

H5

H6

H2

Head

Head = H1+H2+H3+H4+H5+H6

H1 = A2 - B1


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Head MeasurementHead Measurement

Sighting meter (Clinometer) method

Hn = Ln sin where,

H: HeadL: Length of the hypotenuse : Vertical angle

L1

L3

L4

L3

1

2

3

4

H1

H2

H3

H4

Head

Head = H1 + H2 + H3 + H4

Site Survey

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Investigation for Layout and DesignInvestigation for Layout and Design Purpose

To check if the layout of the structure is feasible To select a suitable site for each structure

considering the topographical and geologicalconditions

Investigation Walk along the river and/or route of the prospective

waterway Draw a sketch of the geological and topographical

conditions and possible layout of the structure onthe route map, which was enlarged from the1/50,000 maps.

Measure the dimensions of the structure. Check if there are any obstructions, such as

landslides, cliffs, artificial structures and so on Take pictures of the site of the structures


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Components of a MicroComponents of a Micro --Hydro Power PlantHydro Power Plant

HeadraceWeir and Intake

Spillway

River

Powerhouse

Tailrace

Turbine/Generator Penstock

ElectricalLines

Forebay

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Requirements for Structure LayoutRequirements for Structure Layout Whole System

High head with shorter waterwayWaterfall, steep river slope, etc.

Good accessibility for construction and O&M

Weir and Intake Site Shorter river width and straight river alignment Less river deposit covered Stable slopes on river banks

No or minimal impact to existing water usage and structure OthersUse of existing structuresUse of natural topographical features (natural weirs,ponds)

Headrace Stable slope (no landslides or collapses) Easy to construct open canal, (otherwise, pipes or siphons) Others

Use of existing structure such as irrigation canal


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Requirement for Structure LayoutRequirement for Structure Layout

Forebay Stable and relatively flat land

Easy to install spillway from the forebay

Penstock Shorter length of penstock Good hydraulic gradient

Penstock

MinimumPressure

Negative Pressure

Head Tank

Powerhouse

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Requirement for Structure LayoutRequirement for Structure Layout Powerhouse

Good accessibility Stable foundation Safe from floodwaters

Lets Check! Experience in developing countries. The powerhouse was submerged during floods. The elevation of the powerhouse was too low because:

Traces of floods were not investigated. Local residents were not interviewed about flood

levels in the past. The powerhouse was elevated and the equipment was

repaired.


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StructureStructure --Site InvestigationSite Investigation Intake SiteIntake Site

To determine the approximate location of the weir and intake Approximate location with altimeter or portable GPS To find the suitable place (the river width is narrow !)

To investigate conditions at/around the prospective site Distribution of thick loose sand deposits Scale of landslides/collapses Existing artificial structure

To draw sketches and to take photographs Photographs of the site Sketch of the layout plan and geographic condition

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StructureStructure --Site Investigation (Headrace)Site Investigation (Headrace) To measure the head and length of waterway route

Head and length of a waterway route measured with a hand-leveland/or a distance meter or measuring tape

To investigate the surrounding conditions Unstable slopes such as landslides and collapses Cliffs that present difficulty in laying out waterways Vegetation Inflow or outflow

To draw sketches and to take photographs

Photographs of the site Sketch of the layout plan and geographic condition


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StructureStructure --Site Investigation (Site Investigation ( ForebayForebay and Penstock)and Penstock)

To investigate the forebay site Suitable location for the forebay site

Relatively flat land Adequate space for construction

Approximate location measured with altimeter or portable GPS To investigate the penstock route

Length of the penstock measured with distance meter or measuringtape

Geological and topographical conditions

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StructureStructure --Site Investigation (Power house)Site Investigation (Power house) To investigate the slope condition

Unstable slopes, such as landslides or collapses behind thepowerhouse site

To measure the approximate location Approximate elevation measured with altimeter and portable GPS unit Head between forebay and powerhouse measured with sight meter

(hand-level) and distance meter To investigate the land use conditions

Location of artificial structures near the powerhouse site, if any To investigate tailrace route

Location of tailrace outlet Length of tailrace measured with a measuring tape To take photographs and draw sketches

Photographs and sketches of powerhouse site


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StructureStructure --Site InvestigationSite Investigation(Transmission/Distribution Line)(Transmission/Distribution Line)

To survey the geological and topographical conditions from thepowerhouse site to the load center

To select a transmission line Along existing road or footpath

To measure the length of the transmission route Length of transmission route using measure tape or distance

meter

To trace transmission line on maps

To take photographs and draw sketches of powerhouse site Photographs and sketches of powerhouse site

Site survey

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Investigation for Demand ForecastInvestigation for Demand Forecast Method:

Collection of socio-economic data from local government Interviews with local residents Observations at villages

Items to be investigated Basic demand:

Number of householdsHouse distributionDistance from powerhouse site

Public facilities Needs for electricity:

Existing equipmentEquipment and facilities to be installed after electrificationLivelihood activities

Capacity and willingness to pay:Capacity and willingness to pay for electricityIncome of residentsExpenditure on energy, kerosene, dry cells, etc.

Interview sheet


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Other Outline SurveyOther Outline Survey

Access Road (required time, distance from main town,

road condition) Circumstances of the existing system and future plans Circumstances of river water utilization Existence of other development plans/projects Civil structures in adjacent areas and materials used Presence of natural topographical features and existing

structures that can be used in power generation Existence of important ground features and vegetation

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Types of Structure LayoutTypes of Structure LayoutShort Penstock

Exposed to the greater risk ofblockage or of collapse ordeterioration as a result of poormaintenance. Installing thechannel across a steep slopemay be difficult and expensive.

The risk of a steep slope toerosion makes the shortpenstock layout anunacceptable option, becausethe projected operation andmaintenance cost of thescheme could be veryexpensive, and it may outweighthe benefit of the initialpurchase costs.


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Types of Structure LayoutTypes of Structure Layout

Long PenstockThis layout is necessary if the terrain does not allow the construction of

a channel. However, precautions must be considered. Ensure that seasonal flooding of the river will not damage ordeteriorate the penstock.

Calculate the most economic diameter of the penstock. In the case ofa long penstock, the cost will be particularly high.

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Types of Structure LayoutTypes of Structure LayoutMid-length Penstock

The cost of constructing a channel across the steep slope can beavoided.

This option is preferable when there are signs of instability in the steepslope.


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Check ListCheck ListCheck List

Investigation for generation planning Water flow measurement

Cross section measurement Water velocity measurement Recent ra infall condition Usua l flow condition in th e dry season

Head Measurement Length of waterway Gross head

Investigation for layout and design of facilities Intake site

Approximate elevation and coordinates of the weir Length of weir crest Flood water level River deposit covered Outcrops of base rock in the river bed Stable slope in river banks (land slide, collapse) Artificial structures Drawing sketches Taking photographs

Waterway route Head and length of waterway Unstable topographical condition (landslide, collapse and

cliff) Approximate elevation and coordinates of forebay Drawing sketches Taking photographs

Powerhouse site Length of Penstock Head between powerhouse and forebay Unstable topographical condition (landslide, collapse) Approximate elevation and coordinates of powerhouse

and tailrace outlet Flood water level Length of tailrace Artificial structures Drawing sketches Taking photographs

Transmission line route Length of transmission line Condition of access road Drawing sketches Taking photographs

River and basin condition Vegetation in the basin Existence of landslide and collapse Water use condition in the basin

Taking photographs

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Survey Sheet (General Information)Survey Sheet (General Information)Province Date

Location

MICRO-HYDRO POWER PROJECT

Survey Location of site Potential Surveyor

1. General Data of Region

1.1 Province

1.2 Regency

1.3 Municipality

1.4 Village

1.5 Orchard

2. Accessibility

2.1 From Regency to the Municipality

2.1.1 Distance km ( map information,informal, data )

? asphalt: km ? rocks: km ? soil: km2.1.2 Road condition

? others: km

2.1.3 Trip time

? public vehicle/bus ? motorcycle2.1.4 Transportation Mode

? ship /ferry ? others:........................

Note :

(Explain the trip route, raod condition (good-bad-danger, etc), transportation mode, where to change the vehicle (route) and other

information that needed to get the complete description how to get to the location )

2.2 From Municipality to Village

2.2.1 Distance km ( map information, informal, data )

? asphaltl: km ? rocks: km ? soil: km2.2.2 Road condition

? others: km

2.2.3 Trip time

? public vehicle/bus ? motorcycle2.2.4 Transportation mode

? ship/ferry ? others :........................

Catatan :

(Explain the trip route, road condition (good-bad-danger, etc), transportation mode, where to change the vehicle (route) and other

information that needed to get the complete description how to get to the location )

3. Demography Location of MHP Potential

3.1 Total population person

3.2 Total Family Head family head

3.3 Total house house

3.4 Living source

3.5 Population Distribution * ? spread ? centralized ? grouping ? ..........

3.6 Income per month (in average)

? Multi-purpose ? farmer group ? religious

groups

3.7 Public Organization

? ? ?

3.8 Cooperatives ? ?

*population distribution is described in village map (draft)

1. Village Infrastructure (make village situation map: information in village office, mapping with GPS

and supporting equipment)

4.1 Distance to the neasrest PLN

lines

km (measure with GPS & the available

equipment)

4.2 Public Facility

4.2.1 School ? Elementary School? Junior High School ?Senior High School ? Other: ...........

4.2.2 House of Worship ? mosque ? church ? other .........

4.2.3 Health Services ? local government clinic ? others: .........

4.2.4 Govenment Office ? village ? municipality ? other .........

Others ...............

4.3 Limit of Village

4.3.1 North

4.3.2 South

4.3.3 West

4.3.4 East

4.4 Productive Business

4.4.1 Market ? none ? exist ? daily ? weekly

4.4.2 Small industry ( type & total )

4.4.3 Others

4.5 Economy Potential

( farming,planting,fishery,etc.)

Notes:


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Survey Sheet (river flow measurement)Survey Sheet (river flow measurement)

Place of survey date time : water level

No.Distance from left bankDepth of river

Area of flow sectionWater de th Discharge

Water de th Discharge




Average of V elocity (cm/s)dischage(l/s)

Depth at point and velocity(cm, cm/ s)

60.0

Cross Section of river0.0

10.0

50.0

40.0

30.0

20.0

10 116 7 8 91 2 3 4 5

- 3

-2

0 -

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Interview SheetInterview SheetHousehold number

Name of Respondent

Sub unit of village

Barangay (village)

Circle the final result of the visit to this household1. Completed2. No household member at home or no competent respondent at home at time of visit3. Postponed4. Refused5. Other (specify)

Interviewers nameDateTime interview beganTime interview completed

Data input by Final Check by

1. FAMILY PROFILE

1. Number of family members (only living together in the same house)Male adults at 20 yrs or over personsFemale adults at 20 yrs or over personsChildren less than 20 yrs old personsTotal persons

2. Number of school going childrenUniversity student personsHigh school student personsJunior high school student personsElementary school student personsTotal persons

3. How many of your family are earning income in the village in the village? persons

4. How many of your family members are living in other town to work? persons

5. Is your household headed by male or female?

Tick ( )MaleFemale

6. Which organization does any of your family belong

Barangay Cooperative Persons

Barangay Council PersonsOther (specify) Persons

1. How many of your family members graduated from (upper) high school? persons

2. Housing2. How many rooms does your house have? rooms (including kitchen)

3. What is floor area of your house? m 2

4. What type of roof is used for the house?Type of roof Tick ( )

Tiled roofGI Sheet roofThatched roof (straw, palm leaf)

3. Economic aspects3-1. Household income

5. How much is your family earning from agriculture?Type ofcrops

Averageamount of

production percropping (kg)

Times ofcropping per year

Averagefarm gate

price (Rp.)

Approximate annualearning(Rp.)

Averageannual cost

(Rp.)

Subsistence/cash crop

Rice Subsistence/cash cropSubsistence/cash crop Subsistence/cash crop Subsistence/cash crop Subsistence/cash crop

6. Earnings from FisheryType of fish Annual average

earning (Rp.)Annual average

cost (Rp.)Subsistence/cash

Subsistence/cash Subsistence/cash Subsistence/cash Subsistence/cash

7. What kind of income sources does your family have? Insert the amount of earning of the lastmonth in each category by each income earner.

Income earner Income source

1st incomeearner

2nd incomeearner

3rd incomeearner

4th incomeearner

5th incomeearner

Salaries/wages

Pension

Handicraft

Other cottage industry

Site Survey


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Sketch of Site SurveySketch of Site Survey

Structure-Site Investigation Intake Site

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Float Measuring Method1. Selection of measuring point

Strait axis of stream Uniform cross section of the river

2. Measure flowing distance (=L)

More than width of the river 3. Measure several cross-sectional areas (=A mean )4. Float from the upper section to the downstream

section5. Measure the time that it takes to flow between two

section (=T mean ) Measurement should be done several times.


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5. Flow velocity calculationVm = C Vmean = C L/Tmean

where,C: (1) Concrete channel with uniform cross section = 0.85

(2) Small stream where the riverbed is smooth = 0.65(3) Shallow flow (about 20 ft) = 0.45

(4) Shallow and the riverbed is not flat = 0.25Vmea

Vm= 0.85 V mean

Vmea

Vm= 0.65 V mean

Vmea

Vm = 0.45 V mean

0.5 m

Vmea

Vm = 0.25 V mean

0.5 m

6. River flowQ = V m Amean

4-2-1 preliminary site survey.pdf

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