hh1: 2019 regional & reconstructed hydrology

HH1: 2019 REGIONAL &

RECONSTRUCTED HYDROLOGY

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HH1: 2019 REGIONAL &

RECONSTRUCTED HYDROLOGY

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Table of Contents 1. Introduction ........................................................................................................................... 10

2. Overview/Purpose/Objective ............................................................................................... 11

3. Summary of 2013 Regional & Reconstructed Hydrology Analysis .................................... 12

3.1 Background .................................................................................................................... 12

3.2 Products ......................................................................................................................... 12

3.3 Methods & Data Sources .............................................................................................. 12

4. Need for Updated Analysis ................................................................................................... 13

5. Updated Reservoir Inflow Records ...................................................................................... 13

5.1 Rafferty Inflows .............................................................................................................. 14

5.1.1 Application of Reverse Routing ............................................................................. 14

5.1.2 Rafferty to Boundary Pumped Flows .................................................................... 14

5.1.3 Net Evaporation – Rafferty Reservoir ................................................................... 15

5.2 Grant Devine Inflows ..................................................................................................... 18

5.2.1 Net Evaporation – Grant Devine Reservoir .......................................................... 18

5.3 Boundary Inflows ........................................................................................................... 20

5.3.1 Net Evaporation – Boundary Reservoir ................................................................ 22

5.4 Water Allocation and Licenses – Canadian Reservoirs .............................................. 23

5.4.1 Consumptive Water Use – Boundary Reservoir ................................................... 23

5.4.2 Consumptive Water Use – Rafferty Reservoir ...................................................... 24

5.4.3 Consumptive Water Use – Grant Devine Reservoir ............................................. 24

5.5 Seepage Loses – Canadian Reservoirs ....................................................................... 25

5.6 Lake Darling Inflows ...................................................................................................... 26

5.6.1 Precipitation and Evaporation Data Used ............................................................ 29

5.6.2 Consumptive & Water Supply Usages Downstream of Lake Darling ................. 39

5.6.3 Reverse Routing – Mass Balance Analysis: Lake Darling Inflows ...................... 40

5.6.4 Routing Method: Lake Darling Inflows .................................................................. 42

5.6.5 HEC-ResSim Verification of Lake Darling Inflows ................................................ 46

5.6.6 Local Flow Hydrograph: Sherwood, North Dakota to Lake Darling ..................... 51

6. Summary of 1930-1945 Extension ..................................................................................... 52

6.1 Saskatchewan 1930—1945 Record Extension .......................................................... 52

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6.1.1 Active Gage Sites 1930-1945 ............................................................................... 52

6.1.2 1930-1945 Souris Headwaters Gage (Estevan) & Tributary Inflow Record

Extension ............................................................................................................................... 53

6.1.3 1930-1945 Raffegrty Inflows ................................................................................ 59

6.1.4 1930-1945 Boundary Inflows ............................................................................... 60

6.1.5 1930-1945 Grant Devine Inflows ......................................................................... 60

6.1.6 1930-1945 Local Flow Estimation ....................................................................... 60

6.2 North Dakota Record 1930-1946 Extension .............................................................. 66

6.2.1 Relevant Streamflow Gages (Active & Inactive) ................................................... 70

6.2.2 1930-1945 Mainstem Souris River – Approximation of Flow ............................ 70

6.2.3 1930-1945 Approximation of Tributary Contributions ........................................ 76

6.2.4 1930-1945 Local Flow Estimation ....................................................................... 85

6.3 Summary of 2012-2017 Extension ............................................................................. 95

6.3.1 Products .................................................................................................................. 95

6.3.2 Data Sources .......................................................................................................... 97

6.3.3 Methodology ........................................................................................................... 98

6.3.4 2012-2017 Canadian Dams to Sherwood, ND .................................................... 98

6.3.5 2012-2017 Sherwood, ND to Minot, ND ........................................................... 104

6.3.6 2012-2017 Minot, ND to Bantry, ND ................................................................ 108

6.3.7 2012-2017 Bantry, ND to Westhope, ND ......................................................... 112

7. Data Limitations & Recommendations for Future Study ................................................ 141

7.1 Hydrologic Routing ..................................................................................................... 141

7.1.1 Identified Limitations .......................................................................................... 142

7.1.2 Recommendation for Future Study.................................................................... 142

7.2 J. Clark Salyer Refuge Structures .............................................................................. 142

7.2.1 Identified Limitations .......................................................................................... 142


7.3 Negative Flows ........................................................................................................... 142

7.3.1 Identified Limitation ............................................................................................ 143

7.3.2 Recommendation for future study ..................................................................... 144

7.4 Streamflow Data Availability & Quality ...................................................................... 145

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7.5 Characterization of Direct System Loses and Gains ................................................ 146



8. Application .......................................................................................................................... 146

9. References ......................................................................................................................... 148

Figures

Figure 1. Monthly correlation between Regina and Estevan: Gross Evaporation .................. 16

Figure 2. Mean annual Gross Evaporation ................................................................................. 17

Figure 3. Adopted Inflows to Boundary Reservoir (Red) vs Reverse Routed (Blue): 1958-59

....................................................................................................................................................... 21

Figure 4. Adopted (Red) and Computed Inflows (Blue) to Boundary Reservoir: 1962-1979 . 22

Figure 5. Criteria for Interpolating Between Missing Elevation Measurements ...................... 28

Figure 6. Location of Foxholm 7 N, ND US Precipitation Gage and location of Minot

Experiment Station, ND US Precipitation and Evaporation Gage ............................................. 30

Figure 7. Mean Annual Gross Evaporation (mm) in Saskatchewan: 1971 to 2000 ............... 33

Figure 8. Mean Annual Gross Evaporation (mm) for 1977-2006 ............................................ 34

Figure 9. Mean Annual Gross Evaporation (mm) in Saskatchewan: 1981 to 2010 ............... 35

Figure 10. Mean Annual Gross Evaporation Isopleths extended to Lake Darling, MN ........... 36

Figure 11. Evaporation Reference sites ..................................................................................... 39

Figure 12. 1948 Lake Darling Inflows- Reverse Routed (Blue) & Routed (Sherwood + Local

Flows; red) ................................................................................................................................... 43


Flows; red) .................................................................................................................................... 44


Flows; red) .................................................................................................................................... 45

Figure 15. Reverse Routing Verification 1967-1970 ................................................................ 47



Figure 18. Computation of NET: Evaporation – Precipitation Timeseries ............................... 51

Figure 19. Estimated (Flow Duration Curve Method) vs Observed Flows - Long Creek near

Estevan ........................................................................................................................................ 54

Figure 20. Long Creek near Estevan- Adopted flows. ............................................................... 55

Figure 21. Observed vs. Estimate Flows Souris River near Estevan ....................................... 56

Figure 22. Adopted flows for the Souris River near Estevan ................................................... 57

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Figure 23. Observed vs estimated flows for Moose Mountain Creek near Oxbow ................ 58

Figure 24. Adopted flows for Moose Mountain Creek near Oxbow ......................................... 59

Figure 25. Estimated inflows to Rafferty Reservoir for the period 1930 – 1945 ................... 60

Figure 26. ResSim Network utilized to calculate the local flows for the period 1930 – 1945

....................................................................................................................................................... 61

Figure 27. Routing Network: Souris River near Estevan to Souris River near Sherwood for

1930 – 1945 ............................................................................................................................... 64

Figure 28. Observed flows versus ResSim output for the Souris River near Oxbow .............. 65

Figure 29. Observed flows versus ResSim output for the Souris River near Sherwood ......... 66

Figure 30. Streamflow estimation points: Sherwood to Westhope .......................................... 67

Figure 31. Computation nodes requiring streamflow inputs .................................................... 69

Figure 32. Current estimation and prior reconstructed data of Lake Darling inflow .............. 71

Figure 33. Souris River flow at USGS station above Minot ....................................................... 72

Figure 34. Comparison of Observed vs. Estimate Flows (MOVE.1) at Verendrye. .................. 74

Figure 35. Comparison of Observed vs. Estimate Flows (MOVE.1) at Bantry. ......................... 75

Figure 36. Correlation of Souris at Sherwood and Wintering at Karlsruhe ............................. 77

Figure 37. Wintering River-Comparison of Observed vs. Estimate Flows (MOVE.1) ............... 78

Figure 38. Observed and estimate flows at Des Lacs River at Foxholm hydrometric station

(NS= 0.26). .................................................................................................................................. 79

Figure 39. Reconstructed and observed flows at Willow Creek using the FDC approach. ..... 80

Figure 40. Reconstructed and observed flows at Cut Bank Creek ........................................... 81

Figure 41. Reconstructed and observed flow at Deep River using the FDC approach ........... 82

Figure 42. Reconstructed and observed flows at Stone Creek using the MOVE.1 approach.83

Figure 43. Estimated and Observed flows at Boundary Creek. ............................................... 84

Figure 44. Adopted vs Routed Flow at Lake Darling ................................................................. 86

Figure 45. Observed and Reconstructed flow of the Souris River at Minot (1930 -1936)..... 88

Figure 46. Observed and Reconstructed flow of the Souris River at Minot (1937 - 1945).... 89

Figure 47. Observed and Reconstructed flow of the Souris River at Verendrye (1930 - 1945)

....................................................................................................................................................... 90

Figure 48. Observed and Reconstructed flow of the Souris River at Bantry (1930 - 1945) .. 91

Figure 49. Observed and reconstructed flow of the Souris River at Westhope (1930 – 1935)

....................................................................................................................................................... 93


....................................................................................................................................................... 95

Figure 51. Rafferty Reservoir to Sherwood Schematic ............................................................. 98

Figure 52. HEC-ResSim Routing Model Network – Rafferty Reservoir to Sherwood ........... 100

Figure 53. Observed vs. Modeled Discharge - Sherwood, 2013 ........................................... 102

Figure 54. Observed vs. Modeled Discharge - Sherwood, 2014 ........................................... 103

Figure 55. Sherwood to Minot Schematic ............................................................................... 104

Figure 56. HEC-ResSim Routing Model Network – Lake Darling to Minot............................ 106

Figure 57. Observed vs. Modeled Discharge - Minot, 2013 .................................................. 107

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Figure 58. Observed vs. Modeled Discharge - Minot, 2014 .................................................. 108

Figure 59. Minot to Bantry Schematic ..................................................................................... 109

Figure 60. HEC-ResSim Routing Model Network - Minot to Verendrye ................................. 110

Figure 61. Observed vs. Modeled Discharge - Verendrye, 2013 ........................................... 111

Figure 62. Observed vs. Modeled Discharge - Verendrye, 2014 ........................................... 112

Figure 63. HEC-ResSim Routing Model (from the 2013 Souris River Feasibility Study) ..... 114

Figure 64. Annual Spring Maximum Flows - Boundary Creek vs. Deep River ....................... 117

Figure 65. Observed vs. Modeled Spring Maximums - Boundary Creek near Landa, ND ... 118

Figure 66. Observed vs. Modeled Discharge, Boundary Creek near Landa, 1974 .............. 119

Figure 67. Observed vs. Modeled Discharge, Boundary Creek near Landa, 1999 .............. 120

Figure 68. Annual Spring Maximum Flows - Stone Creek vs. Boundary Creek..................... 121

Figure 69. Observed vs. Modeled Spring Maximums - Stone Creek near Kramer, ND ........ 122

Figure 70. Observed vs. Modeled Discharge - Stone Creek, 1987 ....................................... 123

Figure 71. Observed vs. Modeled Discharge - Stone Creek, 1999 ....................................... 124

Figure 72. Cut Bank Creek at Upham, ND Map ...................................................................... 125

Figure 73. Observed vs. Modeled Discharge - Cut Bank Creek, 1975 .................................. 127




Figure 77. Pool 320, Extended Guide Curve ........................................................................... 133





Figure 82. Observed vs. Modeled Discharge - Westhope, 2011 ........................................... 138




Tables

Table 1. Summary of where Net Evaporation, Direct Water Usage and Seepage is modeled

....................................................................................................................................................... 14

Table 2. Reported pumping from Rafferty to Boundary Reservoir ........................................... 15

Table 3. Assumed monthly distribution of water pumped from Rafferty to Boundary (dam3)15

Table 4. Generation of Daily Precipitation Record – Grant Devine Reservoir ......................... 19

Table 5. Drainage Area Ratio: Crosby to Noonan ...................................................................... 20

Table 6. Current Water license for Boundary Reservoir ............................................................ 23

Table 7. Estimated monthly distribution (%) of Largest Water License Usage from Boundary

Reservoir – Power Generation .................................................................................................... 23

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Table 8. Estimated monthly (%) distribution of 2nd Largest Water License Usage - Municipal

Water Use ..................................................................................................................................... 24

Table 9. Current Water license from Rafferty Reservoir. .......................................................... 24

Table 10. Rafferty Water Usage monthly distribution in % ....................................................... 24

Table 11. Current water licenses from Grant Devine Reservoir. .............................................. 25

Table 12. Monthly water use distribution for Grant Devine in % .............................................. 25

Table 13 Average monthly Rafferty Reservoir inflows with and without seepage from 1992-

2017 ............................................................................................................................................. 26

Table 14. Available Streamflow and pool elevation data for Lake Darling Reservoir ............. 27

Table 15. Development of Precipitation Timeseries ................................................................. 31

Table 16. Gross Evaporation Comparisons- Meyer’s Equation– Estevan to North Dakota

Stations ......................................................................................................................................... 38

Table 17. Gross Evaporation: Meyer’s Equation (for Estevan) vs. Adjusted ND Class A Pan

Evaporation .................................................................................................................................. 38

Table 18. Lake Darling Elevation-Area-Capacity Curve ............................................................. 41

Table 19. Drainage Area Analysis Sherwood to Lake Darling ................................................... 42

Table 20. Computation of NET: Evaporation – Precipitation Timeseries ................................. 50

Table 21. Summary of the active hydrometric stations in Saskatchewan for the period 1930-

1945 ............................................................................................................................................. 52

Table 22. Nash-Sutcliffe coefficients – Sherwood, ND is long-term station ............................ 53

Table 23. Local drainage areas between Souris River - Estevan and Souris River - Sherwood

....................................................................................................................................................... 62

Table 24. Locations Requiring Flow Approximation: Sherwood to Westhope ......................... 68

Table 25. List of gage stations with data periods ...................................................................... 70

Table 26. NSE Values of estimated and observed flows .......................................................... 73

Table 27. Methods used for flow estimation of the Des Lacs River ......................................... 76

Table 28. NSE value of Observed and Simulated streamflow of tributaries ........................... 85

Table 29. Drainage Area Ratios- from Lake Darling to Minot ................................................... 87

Table 30. Distribution of Local Flow from Foxholm to Minot .................................................... 89

Table 31. Drainage Area Distribution: Minot to Verendrye ....................................................... 90

Table 32. Total ungagged local flow from Bantry to Westhope ................................................ 92

Table 33. Drainage area analysis Bantry to Westhope and Drainage Area Ratios with Deep

River .............................................................................................................................................. 94

Table 34. Timeseries Estimated for 2012-2017 Extension...................................................... 96

Table 35. Local Flow Timeseries Estimated for 2012-2017 Extension ................................... 97

Table 36. Rafferty Reservoir to Sherwood Routing Parameters ............................................... 99

Table 37. Rafferty Reservoir to Sherwood Local Flow Reach Parameters ........................... 100

Table 38. Rafferty Reservoir to Sherwood Drainage Areas .................................................... 101

Table 39. Sherwood to Lake Darling Drainage Areas ............................................................. 105

Table 40. Lake Darling to Minot Local Flow Reach Parameters ............................................ 106

Table 41. Minot to Bantry Drainage Areas .............................................................................. 109

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Table 42. Minot to Bantry Local Flow Reach Parameters ...................................................... 110

Table 43. Pertinent Streamflow Gages from Bantry to Westhope ........................................ 115

Table 44. Drainage Areas between Bantry, ND and Westhope, ND ...................................... 116

Table 45 - Ungaged Local Flow Distribution between Bantry, ND and Westhope, ND ........ 116

Table 46. Cut Bank Creek Contributing Drainage Areas (Cont.D.A) ...................................... 126

Table 47. Monthly Total Evaporation J. Clark Salyer Refuge Structures ............................... 131

Table 48. J. Clark Salyer National Wildlife Refuge Water Management Plan ....................... 132

Appendices

Appendix A: Streamflow/Stage Gage Inventory

Appendix B: Topology Diagram

Appendix C: Souris River Basin Map

Appendix D: HH1 Product List

Attachments

Attachment 1: 2013 Regional and Reconstructed Hydrology Study

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1. Introduction

The Souris (Mouse) River originates in the Province of Saskatchewan, passes through the state

of North Dakota, and then crosses into the province of Manitoba before joining the Assiniboine

River (see map, Appendix C). Unprecedented flooding in the Souris River Basin in 2011 has

focused attention on review of the Operating Plan contained in Annex A to the 1989

International Agreement (Reference 1). Interests in the basin, particularly in North Dakota, have

asked that additional flood protection measures be evaluated, above and beyond what is currently

provided under the International Agreement, and that the operating plan contained in Annex A

and B of the Agreement be reviewed. In addition, Article V of the Agreement requires that the

Operating Plan be reviewed periodically to maximize the provision of flood control and water

supply benefits that can be provided consistent with the terms of the Agreement. A Plan of Study

targeted at reevaluating the operating plan for the reservoirs comprising the Souris Basin Project

was initiated in 2012. This assessment is being carried out in support of the Plan of Study.

To evaluate proposed changes to the operating plan, alternative reservoir operating rules are

tested using reservoir simulation and routing models over the period 1930 to 2017. The HH1

task, described in this report, consists of generating all of the continuous, daily timeseries

necessary to accurately model the Souris River Basin Project over the 1930 to 2017 period.

These timeseries include intervening local flow and tributary inflow hydrographs along the

mainstem of the Souris River for the drainage area between the three Canadian reservoirs and

Westhope, ND, evaporation at Rafferty, Boundary, Grant Devine, and Lake Darling reservoirs,

and inflows to Rafferty, Boundary, and Grant Devine reservoirs.

The continuous, daily, local flow hydrographs and tributary inflow hydrographs mentioned

above were generated as part of the 2013 Regional and Reconstructed Hydrology Study for the

Souris River Basin (Attachment 1) for the period 1946 to 2012. These local and tributary flow

hydrographs are adopted for the Plan of Study, and additional analysis is completed to extend

those timeseries for the periods 1930 to 1945 and 2013 to 2017.

Although the 2013 study also developed reservoir inflow timeseries for the period 1946 to 2017,

critical losses from the reservoirs were not explicitly modeled. Therefore, the reservoir inflow

timeseries developed in the 2013 study are not adopted for this analysis. Instead, reservoir

inflows are recomputed for the entire 1930 to 2017 period with critical losses from the reservoirs

explicitly modeled.

Data sources used to support this analysis include streamflow and stage data recorded by the U.S

Geological Survey (USGS), Environment and Climate Change Canada (ECCC), the U.S Fish

and Wildlife Service (USFWS) and the U.S Army Corps of Engineers (USACE). Precipitation

data for the United States is acquired from the National Oceanographic and Atmospheric

Administration’s (NOAA) National Center for Environmental Information (previously, National

Climate Data Center NCDC) and Oregon State’s Northwest Alliance for Computation Science

and Engineering (PRISM dataset). Precipitation data used for Saskatchewan is adopted from

ECCC. Adopted Evaporation data is derived using Meyer’s equation and is provided by the

Saskatchewan Watershed Authority (SWA).

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Methods used to approximate flow time series as part of the updated, 2019 assessment include

MOVE.1, MOVE.3, a flow-duration based algorithm, drainage area transfer (general relations)

and reservoir reverse routing (mass balance approach). The record extension technique used for

each site is consistent with the methodology used in the 2013 Regional and Reconstructed

Hydrology Study, except MOVE.1 is at times replaced with MOVE.3. When compared to

MOVE.1 results, MOVE.3 flows are nearly identical. MOVE.3 is used by USACE for this

analysis to comply with the most current guidance issued by the USGS regarding statistical daily

flow estimation techniques (Reference 10). MOVE.1 only uses the statistical properties of the

concurrent portion of the records at the short-term site and the long-term sites to generate a

relationship that can be used to approximate flows at the short-term site. MOVE.3 also includes

the additional record from the long-term site not observed at the short-term site to improve the

estimate. Both the MOVE.1 and MOVE.3 methods are acceptable and widely used means

approximating streamflow records. Relative to simple linear regression both MOVE.1 and

MOVE.3 maintain the natural variability in the streamflow record being extended or filled in.

A USACE Hydrologic Engineering Center’s Reservoir System Simulation (HEC-ResSim) model

is used to simulate reservoir operations and route flows along the mainstem of the Souris River,

along the Des Lacs River, and through the J. Clark Salyer National Wildlife Refuge structures.

Initially, an HEC-ResSim model was developed in support of the 2013 Regional and

Reconstructed Hydrology Study (Attachment 1). The 2013 Regional and Reconstructed

Hydrology ResSim model has been modified since 2013. The majority of the modifications made

to the 2013 HEC-ResSim model have been made to support the Plan of Study. The routing

parameters and the techniques used to model the J. Clark Salyer Refuge structures have not been

significantly modified since 2013. The most recent version of the ResSim model is referred to as

the Plan of Study HH6 product. Relative to the 2013 version of the ResSim model, the HH6

product contains much greater detail in how the reservoirs (Rafferty, Grant Devine, Boundary

and Lake Darling) are modeled in support of water supply operations. Additionally, significant

direct water usages, as well as evaporation and precipitation on the pools are now explicitly

modeled within ResSim. Inputs to the ResSim model are presented within this report.

2. Overview/Purpose/Objective

It is important to ensure appropriate information, modeling tools, and data are collected and

evaluated efficiently for the review of the operating plan. The objective of this analysis is to have

the best practical understanding of the basin responses to hydrological forcing at locations

critical to the operation of the Souris River reservoir system and to generate timeseries data

necessary to simulate reservoir operations over the period 1930 to 2017. This facilitates the

definition of conditions for evaluating proposed changes to Annexes A and B to the 1989

International Agreement for Water Supply and Flood Control in the Souris River Basin.

Homogenous, continuous timeseries datasets are to be compiled representing inflows to and loss

from reservoirs, tributary inflows, and local flow hydrographs. These input timeseries are

ultimately used to simulate reservoir pool elevations and flow records at critical mainstem,

Souris River locations. Throughout the period of record selected for analysis, the basin is only

gaged at a finite number of locations, and for portions of the period of record only a subset of the

gages in the basin are recording data. For each of these components, a separate, practical and

acceptable method needs to be considered to develop a hydrological supply series that will be the

basis of comparison for evaluating proposed changes to the operating plan.

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3. Summary of 2013 Regional & Reconstructed Hydrology Analysis

The 2013 Regional and Reconstructed Hydrology Study (Attachment 1) consisted of developing

homogenous, continuous daily timeseries datasets representative of reservoir inflows, local flow

hydrographs, tributary inflows and mainstem Souris River flows for the period of record from

1946 through 2011.

3.1 Background

Daily flow timeseries along the mainstem of the Souris River were reconstituted for in situ, with

project, and without project conditions (“state of nature”). In situ conditions are defined as the

conditions in the basin which persisted when data was collected. The “with project” condition

refers to the basin condition with the Souris River Basin Project in place. The Souris River

Project consists of Rafferty Reservoir, Boundary Reservoir, Grant Devine Reservoir and Lake

Darling Reservoir. The without project condition (“state of nature”) refers to the Souris River

Basin with the impacts of Rafferty Reservoir, Boundary Reservoir, Grant Devine Reservoir and

Lake Darling Reservoir removed.

3.2 Products

With the exception of the inflow records to the reservoirs and the local flow hydrograph between

Sherwood, North Dakota, and Lake Darling, timeseries data generated between 1946 and 2011 as

part of the 2013 Hydrology Study (Attachment 1) is adopted to support the Plan of Study. The

inventory of streamflow and stage gages conducted as part of the 2013 analysis is adopted to

support the Plan of Study assessment, as well. This inventory is displayed within the tables,

topology diagram and map included as Appendices A, B and C to this report. Methods adopted

as part of this assessment are consistent with the techniques adopted for the 2013 Regional and

Reconstructed Hydrology Study. The complete, 2013 Regional and Reconstructed Hydrology

Study is included as Attachment 1.

As part of the 2013 analysis, HEC-ResSim (Reference 4) was used to generate a homogenous

record representative of current reservoir operating conditions at critical locations along the

mainstem of the Souris River. The 2013 HEC-ResSim model has since been updated as part of

the Plan of Study (HH6 product). The hydrologic, river reach routing relationships used to

reconstitute flows as part of the 2013 analysis are adopted to support the current assessment.

These are the same hydrologic routing parameters adopted within both the 2013 version of the

ResSim model and the updated, HH6 ResSim model.

3.3 Methods & Data Sources

Data sources used to support this analysis include streamflow and stage data recorded by the

USGS, ECCC, the USFWS and the USACE (Appendices A & B). Methods used to approximate

flow timeseries include MOVE.1, a flow-duration based algorithm, drainage area transfer

(general relations), and reservoir reverse routing (mass balance approach). More detail related to

the methodology adopted and the products produced as part of the Regional and Reconstructed

Hydrology Study can be found in Attachment 1.

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4. Need for Updated Analysis

This effort consists of updating data records generated as part of the 2013 Regional and

Reconstructed Hydrology Study analysis to support the Plan of Study. Updates are required to

generate timeseries that cover the full period of analysis for the Plan of Study: 1930 to 2017. As

part of this effort reservoir inflows, tributary inputs and local flow hydrographs are generated for

1930 to 1945 and 2012 to 2017. Analysis is also dedicated to developing timeseries and explicit

modeling techniques to better capture direct inputs and loses to and from the major water

management reservoirs.

The majority of gages in the Souris River Basin were installed after 1930. Between 1930 and

2017 the coverage provided by daily, streamflow recording gages varies considerably. The

operating plan presented in Annex A (Reference 1) was developed based on computer

simulations of floods having temporal and spatial characteristics of those actually experienced in

the floods of 1969, 1974, 1975, 1976, 1979, and 1982 (Reference 1). When testing the validity of

operating plan, the period of record at Sherwood crossing, 1930 to 1988 (58 years of record) was

utilized to determine how many years flood operations would have been applied (Reference 1).

The 2013 Regional and Reconstructed Hydrology Study relied on a period of record from 1946

to 2011 (66 years of record). The limiting factor in deciding upon a period of record for analysis

was the streamflow data available on the Des Lacs River. USGS gage 05116500 located on the

Des Lacs River at Foxholm, North Dakota has the most extensive daily flow record on the Des

Lacs River. The Des Lacs River gage has a period of record from 1946 to present. Additionally,

the scope of the 2013 study was to evaluate hydrologic forcings between the headwaters of the

Souris River and its confluence with the Assiniboine River near Wawanesa, Manitoba. There is

very limited streamflow data available prior to 1946 downstream of Minot, North Dakota.

To support the Plan of Study, stakeholders in Saskatchewan, North Dakota and Manitoba

expressed interest in assessing proposed study alternatives using historic flows from the 1930’s

drought. Thus, as part of the HH1 assessment the timeseries generated in 2013 analysis were

back extended to 1930. In order to take advantage of data collected since 2011 the period of

record adopted for the 2013 Regional and Reconstructed Hydrology Study is extended through

2017.

5. Updated Reservoir Inflow Records

In addition to extending approximations of reservoir inflows back to 1930 and from 2012 to

2017, reverse routed reservoir inputs are recomputed to explicitly account for additional known

direct losses and inputs to the pools. As part of the 2013 Regional and Reconstructed Hydrology

Study (Attachment 1), only a gross approximation of monthly evaporation was directly

accounted for within the reconstructed reservoir inflow timeseries and the HEC-ResSim model.

Precipitation on the pools were implicitly accounted for within the computed inflow records. As

part of this update, precipitation on the pools are accounted for explicitly as a daily timeseries,

and the Meyer’s equation is used to develop more accurate evaporation timeseries. The Meyer’s

equation, an empirical formula that has been widely used across the Canadian prairies for water

supply studies, provides reasonable estimates of evaporation at each reservoir in the absence of

continuous, observed evaporation measurements throughout the period of record. While there is

14

uncertainty in these evaporation estimates, this methodology offers a consistent approach

throughout the 1930 to 2017 analysis period and adequately captures the spatial variability in

evaporation throughout the watershed.

Additional loses and inputs to the reservoirs are also directly accounted for including seepage

loses from Rafferty, direct water usage from Boundary, and pumped flows from Rafferty to

Boundary. By directly defining these contributions and loses from the reservoirs the HEC-

ResSim model becomes more compatible with outputs from rainfall-runoff models. Table 1

summarizes inputs/losses explicitly modeled within ResSim and considered as part of this

analysis in generating reservoir inflow timeseries.

Table 1. Summary of where Net Evaporation, Direct Water Usage and Seepage is modeled

Modeling Approach

Rafferty Reservoir

Boundary Reservoir

Grant Devine Lake

Lake Darling

Net Evaporation External

Timeseries x x x x

Direct Water Use External

Timeseries Included in

Seepage x - -

Seepage Loss Constant Loss

Function x - - -

Pumped Pipeline Flows External

Timeseries x x - -

5.1 Rafferty Inflows

Reservoir inflows to Rafferty Reservoir are calculated by reverse routing recorded outflows from

1992 to 2017. Construction of Rafferty reservoir was completed in 1992. The reservoir initially

filled to its Full Supply Level (FSL) of 550.50 m (1806.10 ft) in 1997.

5.1.1 Application of Reverse Routing

Reverse routing is dependent a mass balance approach where inflows generated by the upstream,

contributing drainage area are assumed to be equivalent to change in storage plus outflows

(releases, evaporative losses etc.), minus any direct inflows to the reservoir (precipitation etc.).

Inflows to Rafferty from the Rafferty to Boundary diversion are subtracted, while pumped flows

from Rafferty into Boundary are added into the inflow calculation. Inflows from the diversion

are recorded by the 05NB038 Environment and Climate Change Canada (ECCC) hydrometric

station, while records of pumped flows to Boundary are obtained from the International Souris

River Basin Annual Reports and Water Security Agency (WSA) water licensing group. For the

elevation-area-capacity curve for Rafferty Reservoir, see Section 3.1 of the HH6 report.

5.1.2 Rafferty to Boundary Pumped Flows

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Table 2 summarizes the annual volume that has been historically pumped into Boundary

Reservoir. This volume is distributed to a monthly time-step (Table 3). Unfortunately, there are

no operating logs of the pump station, therefore, the annual volume is distributed taking into

consideration the reservoir water levels, reported pumped volume, and the water license

requirements. Pumping from Rafferty only occurs when water levels at Boundary are below

559.5 m (1835.63 feet). The maximum pump capacity is 25 dam3/day (20.3 acre-feet/day).

Pumped flows are an outflow from Rafferty and an inflow to Boundary. Data are available from

2002 to 2017 (Reference 20); however, the last year that the pump was operated was in 2009.

For this reason, the years 2010 to 2017 are omitted from the following tables.

Table 2. Reported pumping from Rafferty to Boundary Reservoir

Year Pumped Volume to Boundary (ISRB Report; dam3) Pumped Volume to Boundary (acre-feet)

2002 2,500 2028 2003 1,045 848 2004 640 519

2005 0 0

2006 2,770 2247

2007 3,590 2912

2008 7,680 6229

2009 1,050 852

Table 3. Assumed monthly distribution of water pumped from Rafferty to Boundary (dam3)

Year Unit Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Total

2002 dam3 0 0 0 0 0 0 0 500 500 500 500 500 2,500

acre-feet 0 0 0 0 0 0 0 406 406 406 406 406 2,028

2003 dam3 775 270 0 0 0 0 0 0 0 0 0 0 1,045

acre-feet 629 219 0 0 0 0 0 0 0 0 0 0 848

2004 dam3 0 0 0 0 640 0 0 0 0 0 0 0 640

acre-feet 0 0 0 0 519 0 0 0 0 0 0 0 519

2005 dam3 0 0 0 0 0 0 0 0 0 0 0 0 0

acre-feet 0 0 0 0 0 0 0 0 0 0 0 0 0

2006 dam3 0 0 0 0 0 0 0 554 554 554 554 554 2,770

acre-feet 0 0 0 0 0 0 0 449 449 449 449 449 2,247

2007 dam3 718 718 0 0 0 0 0 718 718 0 0 718 3,590

acre-feet 582 582 0 0 0 0 0 582 582 0 0 582 2,912

2008 dam3 775 700 80 0 775 750 775 775 750 775 750 775 7,680

acre-feet 629 568 65 0 629 608 629 629 608 629 608 629 6,229

2009 dam3 775 275 0 0 0 0 0 0 0 0 0 0 1,050

acre-feet 629 223 0 0 0 0 0 0 0 0 0 0 852

16

5.1.3 Net Evaporation – Rafferty Reservoir

In addition to diverted inflows and pumped outflows, net evaporation (evaporation –

precipitation on the pool) is also accounted for explicitly in both the reverse routing computation

and as a timeseries input to ResSim. Daily precipitation values recorded at the Estevan weather

station are currently being used as the precipitation record for Rafferty. Missing precipitation

data is filled in using regression models and observations recorded at the nearby Macoun,

Saskatchewan and Midale, Saskatchewan weather stations. Table 4 provides a summary of the

stations and periods of times used to fill in missing precipitation records. Monthly evaporation

values computed for Estevan using the Meyer’s equation (References 17 and 18) are used to

define evaporative losses for Rafferty.

The gross evaporation record at the Estevan weather station covers the period 1946 to 2016 and

is extended back to 1930 using the monthly gross evaporation calculated at the Regina weather

station. Figure 1 illustrates the relationship between calculated gross evaporation at Estevan and

Regina for the period 1946 to 2016. Gross evaporation at Estevan for 2017 is filled in by using

monthly mean values calculated over a 30-year period (1987 to 2016).

Figure 1. Monthly correlation between Regina and Estevan: Gross Evaporation

Gross evaporation is adjusted using the mean annual gross evaporation map (Figure 2) to account

for the reservoir’s location relative to Estevan. A factor of 1.043 is applied to the Estevan

17

Evaporation to transfer it to Rafferty’s location (evaporation increases towards the west based on

the historical gross evaporation maps, Figure 2). Once the monthly gross evaporation is adjusted,

the monthly evaporation timeseries is distributed uniformly to generate a daily evaporation

timeseries. Net evaporation (Evaporation-Precipitation) for Rafferty Reservoir is calculated using

the adopted daily precipitation record.

18

Figure 2. Mean annual Gross Evaporation

19

5.2 Grant Devine Inflows

Inflows to Grant Devine are calculated by reverse routing, using recorded outflows at the ECCC

hydrometric stations downstream of the reservoir (05ND004 and 05ND013), primarily recorded

precipitation records at the town of Oxbow, Saskatchewan and adjusted gross evaporation

calculated at Estevan, Saskatchewan. Grant Devine Reservoir was constructed in 1992 and first

reached its full supply level in 1999. For the elevation-area-capacity curve for Grant Devine

Lake, see Section 3.1 of the HH6 report.

5.2.1 Net Evaporation – Grant Devine Reservoir

There are sporadic precipitation records at the town of Alameda from 1951 to 1965. Because

Grant Devine Reservoir is located very close to Alameda, the Alameda measurements are

adopted when available. For the remainder of the period of record precipitation reported at

meteorological station 4015800 located at Oxbow, Saskatchewan (Latitude 49.32, Longitude -

102.12) is used to represent the precipitation record at Grant Devine. The Oxbow precipitation

record contains some periods of missing data, consequently, Oxbow precipitation records are

filled in using data from multiple, nearby weather stations. The Carlyle precipitation record is

used to fill in the data from 1930 to 1933. Data from 1934 to 1948 is filled in using a linear

regression model with records from Estevan and Carlyle. Data from 1948 to 2007 is filled in

using a regression model with the stations located at Carnduff and Willmar. When data is not

available for Carnduff, only Willmar data is used. From 2007 to 2017 a linear regression

relationship with Estevan precipitation data is used to fill in the missing data. How the daily,

precipitation record was compiled for Grant Devine Reservoir is summarized in Table 4.

20

Table 4. Generation of Daily Precipitation Record – Grant Devine Reservoir

Meteorological Gage

(Station #)

Latitude,

Longitude

Data

Source

Period of Record

Available Application

Alameda, Saskatchewan 49.25, -102.28 ECCC 1894-1965 (Sporadic) Adopted where available (1951-1965)

Oxbow, Saskatchewan

(4015800) 49.32, -102.12 ECCC 1949-2018 Adopted where available (if Alameda is inactive)

Carlyle

(4011160) 49.63, -102.27 ECCC 1922-1996

Fill-in Oxbow Data 1930-1933

Fill-in Oxbow 1934-1948 via Regression Equation o Independent variables: Carlyle & Estevan

Precipitation

o Dependent variable: Oxbow Precipitation

Estevan, Estevan A, Estevan

A

(4012390,4012400,4012401)

49.2, -103.07;

49.22,-102.97;

49.21,-102.97

ECCC 1899-1944; 1944-

2015; 2015-2018

Fill-in Oxbow 1934-1948 via Regression Equation o Independent variables: Carlyle & Estevan

Precipitation


Fill-in Oxbow 2007-2017 via Regression Equation o Independent variable: Estevan Precipitation


Carnduff

(4011250) 49.22, -101.75 ECCC 1962-2007

Fill-in Oxbow 1948-2007 via Regression Equation o Independent variables: Carnduff, Willmar

Precipitation

(Willmar only if Carnduff is unavailable)


Willmar

(4018960) 49.42, -102.5 ECCC 1948-2007

Fill-in Oxbow 1948-2007 via Regression Equation o Independent variables: Carnduff, Willmar

Precipitation

(Willmar only if Carnduff is unavailable)


21

Monthly, gross evaporation computed using the Meyer’s equation at Estevan for 1946 to 2016 is

used to define the evaporation record at Grant Devine. A factor of 0.955 is applied to translate

the record at Estevan to the location of Grant Devine. The gross evaporation record at the

Estevan weather station covers the period 1946 to 2016 and has been extended back to 1930

using the monthly gross evaporation calculated at the Regina weather station. Gross evaporation

at Estevan for 2017 is filled in by using monthly mean values calculated over a 30-year period

(1987-2016). Once the monthly gross evaporation is adjusted, it is distributed uniformly to

generate a daily timeseries. Net evaporation (Evaporation minus Precipitation) for Grant Devine

is calculated using the adopted, daily precipitation record.

5.3 Boundary Inflows

Boundary Reservoir was constructed in 1958. The Boundary to Rafferty Diversion was

completed in 1993. There is uncertainty in the quantity of direct water use which occurs at

Boundary Reservoir and it is known that this quantity varies from year to year. As a result,

inflows to Boundary Reservoir are assumed to be equal to the recorded flows at the Long Creek

near Noonan hydrometric station (05NB027) between Oct 1, 1959 and 2017, while recorded

flows at Long Creek near Crosby (05NB026) adjusted for drainage area are considered the most

representative inflow timeseries for 1943 to 1958 and records at Long Creek at Eastern Crossing

of International Boundary (05NB013) are adopted for 1959. Table 5 summarizes the effective

drainage area ratio (1.29) used to adjust the Long Creek near Crosby streamflow record.

Table 5. Drainage Area Ratio: Crosby to Noonan

Station Effective Drainage Area (km2) Effective Drainage Area (mi2) Factor

Long Creek near Crosby (05NB026) 1,129 436 1.16

Long Creek near Noonan (05NB027) 1,315 508 none

Figure 3 illustrates a comparison of the previously calculated flows determined by reverse

routing in the 2013 Regional Reconstructed Hydrology Report (Attachment 1) and the adopted

inflows generated using the recorded timeseries for 1958 to 1959.

22

Figure 3. Adopted Inflows to Boundary Reservoir (Red) vs Reverse Routed (Blue): 1958-59

Figure 4 illustrates a comparison between the adopted inflows to Boundary Reservoir based on

the observed record at Noonan versus the previously estimated inflows determined by reverse

routing for the period 1962 to 1979.

23

Figure 4. Adopted (Red) and Computed Inflows (Blue) to Boundary Reservoir: 1962-1979

5.3.1 Net Evaporation – Boundary Reservoir

Net evaporation (evaporation – precipitation on the pool) is accounted for explicitly as a

timeseries input to ResSim. Daily precipitation values recorded at the Estevan weather station are

used as inputs to the ResSim model for Boundary Reservoir. Missing precipitation data is filled

in using regression models and precipitation records recorded nearby at the Macoun,

Saskatchewan and Midale, Saskatchewan weather stations. Monthly evaporation values

computed for Estevan using the Meyer’s equation (References 17 and 18) are used to define

evaporative losses for Boundary. The gross evaporation record at the Estevan weather station

covers the period 1946 to 2016 and is extended back to 1930 using the monthly gross

evaporation calculated at the Regina weather station. Gross evaporation at Estevan for 2017 is

filled in by using monthly mean values calculated over a 30-year period (1987-2016). The

Estevan gross evaporation record is directly adopted to represent evaporative losses at Boundary.

Monthly gross evaporation values are uniformly distributed to generate a daily, gross

evaporation record for Boundary Reservoir.

24

5.4 Water Allocation and Licenses – Canadian Reservoirs

Direct water usages consist of water being withdrawn directly from the reservoir pool. The most

significant consumptive, direct water uses occur from Boundary Reservoir. An operationally

insignificant amount of direct water use occurs at Rafferty Reservoir and Grant Devine

Reservoir. Thus, the water use at Rafferty and Grant Devine is not explicitly accounted for.

5.4.1 Consumptive Water Use – Boundary Reservoir

There are currently four water allocations from Boundary Reservoir that account for a total

annual diversion of up to 14,851 dam3 (12,040 acre-feet), annually. Table 6 summarizes the

water licenses for Boundary reservoir, the allocations and total diversion.

Table 6. Current Water license for Boundary Reservoir

License # Allocation Losses Diversion

dam3 acre-feet dam3 acre-feet dam3 acre-feet

9093 1,752 1,421 0 0 1,752 1,421

16736 1,300 1,054 0 0 1,300 1,054

5904 8,000 6,488 2,455 1,991 10,455 8,479

1047 1,332 1,080 12 10 1,344 1,090

Total 12,384 10,044 2,467 2,001 14,851 12,045

The direct water use at Boundary Reservoir includes forced evaporation from Boundary

Reservoir which occurs as a result of the Reservoir being used as cooling water for power

generation. Forced evaporation from Boundary Reservoir is accounted for with the water

licensures.

The total maximum volume that has been granted to the two most significant license holders is

simulated explicitly within the Plan of Study HH6 ResSim model. The estimated water use

volume from Boundary reservoir applied in the model is equivalent to the total volume that has

been granted for power generation (11,755 dam3/year [9,534 acre-feet/year] including losses)

and for municipal water supply (3,096 dam3/year [2,511 acre-feet/year]). The annual volumes are

distributed on a monthly basis based on how the water licenses are distributed according to Table

7 and

Table 8. For example, municipal water usage is highest in the summer months so water use is

assumed to be higher during July and August (Table 8). The total diversion volume and

estimated monthly distribution of the water use is used to generate a timeseries of water use for

each month of the year and is input into the ResSim model at Boundary Reservoir.

Table 7. Estimated monthly distribution (%) of Largest Water License Usage from Boundary Reservoir – Power Generation

Total Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec

dam3 acre-feet

25

11,755 9,534 8.1 6.5 6.1 6.1 6.2 7 7 9.3 11.4 11.4 11.4 9.5

Table 8. Estimated monthly (%) distribution of 2nd Largest Water License Usage - Municipal Water Use


dam3 acre-feet

3,096 2,511 7.5 7.5 8 8 8.3 9 10 10 8.2 8 8 7.5

5.4.2 Consumptive Water Use – Rafferty Reservoir

Currently, there are five water licenses for Rafferty that account for an annual volume of 11,702

dam3 (9,487 acre-feet). Over 90% (10,100 dam3) of licensed volume is allocated to power

production. The other three licenses support irrigation, oil recovery, and livestock watering.

Table 9 summarizes Rafferty’s water licenses and their respective allocation.

Table 9. Current Water license from Rafferty Reservoir.

License # Allocation Diversion

dam3 acre-feet dam3 acre-feet

16932 327 265 327 265

17060 250 23 250 23

16275 2,800 2,271 2,800 2,271

16669 7,300 5,921 7,300 5,921

17364 395 320 395 320

Total 11,072 8,980 11,072 8,980

The annual volumes are distributed by month in

Table 10. The water allocated for power production (~90%; cooling water) is distributed using

the same monthly distribution as is applied to Boundary reservoir (Table 7). Water from Rafferty

to Boundary reservoir is diverted using the pump line, therefore the same monthly distribution

was used. The other three allocations are distributed according to the purpose of the water

license. Because Rafferty’s direct water usage is relatively small, water supply loses are not

explicitly accounted for in either the reverse routing computation or the HEC-ResSim model.

Table 10. Rafferty Water Usage monthly distribution in %


dam 3 acre-feet

327 265 0.0 0.0 0.0 0.0 15.0 20.0 25.0 25.0 15.0 0.0 0.0 0.0

250 203 8.3 8.3 8.3 8.3 8.4 8.4 8.4 8.4 8.3 8.3 8.3 8.3

395 320 8.3 8.3 8.3 8.3 8.4 8.4 8.4 8.4 8.3 8.3 8.3 8.3

26

5.4.3 Consumptive Water Use – Grant Devine Reservoir

Currently there is only one water license for Grant Devine reservoir that is for a total of 55 dam3

(44.59 acre-feet; Table 11). The monthly distribution based on the distribution of water licenses

adopted for Grant Devine’s annual water usage is summarized in Table 12. Because Grant

Devine’s direct water usage is relatively small, water supply loses are not explicitly accounted

for in either the reverse routing computation or the HEC-ResSim model.

Table 11. Current water licenses from Grant Devine Reservoir.

License # Allocation Losses Diversion

dam3 acre-feet dam3 acre-feet dam3 acre-feet

16672 55 45 0 0 55 45

Table 12. Monthly water use distribution for Grant Devine in %


dam3 acre-feet

55 45 0.0 0.0 0.0 0.0 15.0 20.0 25.0 25.0 15.0 0.0 0.0 0.0

5.5 Seepage Loses – Canadian Reservoirs

Reverse routing relies on a mass balance computation and thus the resulting inflow record will

include any errors in observed data and the cumulative effect of any losses or gains that were not

explicitly accounted for. When the cumulative impact of net losses not directly accounted for is

greater than the amount of runoff which reached the reservoir (or other sources of inflow not

explicitly accounted for) this results in a negative computed inflow. Studying significant and

reoccurring instances of negative inflows can provide insight into unaccounted for losses.

Based on the Rafferty Reservoir reverse routing computation, on average Rafferty is presenting a

total negative inflow volume of approximately 14,700 dam3/year (11,917.48 acre-feet/year) that

can be attributed at least in part to a seepage loss due to the little water use from the reservoir.

Table 13 shows the average monthly reverse routed inflows for Rafferty Reservoir from 1992 to

2017 when seepage is not explicitly accounted for. During the winter months, when the reservoir

is iced over, a negative inflow of roughly 0.283 m3/s (10 ft3/s) was computed using reverse

routing. Since evaporation is typically negligible during the winter months and there does not

appear to be direct water use that can explain this loss, it can likely be attributed to seepage. A

minimal amount of direct water usage does occur, but it is an order of magnitude lower than the

computed negative, inflow volumes.

27

Table 13: Average monthly Rafferty Reservoir inflows with and without seepage from 1992-2017

Month Avg. Monthly Inflow Avg. Monthly Inflow with seepage

ft3/s m3/s ft3/s m3/s

1 -8.7 -0.25 2.4 0.07

2 -9.7 -0.27 1.4 0.04

3 108 3.06 119.2 3.38

4 533.3 15.10 545.1 15.44

5 250.1 7.08 262.3 7.43

6 285.3 8.08 297.5 8.43

7 101.7 2.88 113.8 3.22

8 17.3 0.49 29.3 0.83

9 -4.3 -0.12 7.5 0.21

10 -14.7 -0.42 -3 -0.08

11 -29.8 -0.84 -18.1 -0.51

12 -11.8 -0.33 -0.5 -0.01

A seepage loss that is assumed to be constant at all pool elevations is unlikely and would result

in disproportionally high losses when the pool is low. Estimates of seepage loss rates based on

local soil properties were provided by the WSA for Rafferty Reservoir. These relationships were

used to develop a function which assigns a seepage loss to the reservoir for a given observed

pool elevation. A linear seepage relationship varying from 0.51 m3/s (18 ft3/s) at the Maximum

Allowable Flood Level (MAFL) of 554.0 m (1817.59 ft) to 0 m3/s (0 ft3/s) when the pool is dry

is used. This results in an average seepage of roughly 0.283 m3/s (10 ft3/s). The seepage loss is

assumed to include the known (but, relatively insignificant) direct water use.

Inflows were recomputed using the seepage function. The average monthly inflows computed

after seepage is directly accounted for are summarized in Table 13, which shows that when

seepage is considered in the calculation, the average inflow value is closer to zero which is what

is expected during the winter months.

On average Grant Devine presents a negative inflow volume of approximately 3,500 dam3/year

(2,827.5 acre-feet/year) that can also be attributed to seepage due to the almost non- existent

water use. Because this is such a small quantity it is not directly accounted for within the reverse

routing calculation or the HEC-ResSim model.

5.6 Lake Darling Inflows

Lake Darling Dam was constructed in 1936. Observed, daily elevation data for Lake Darling and streamflow records collected at the four locations listed in Table 14 are used to generate the local

28

flow hydrograph between Sherwood, North Dakota and Lake Darling, as well as the in situ

condition inflow record to Lake Darling.

Table 14. Available Streamflow and pool elevation data for Lake Darling Reservoir

Source Gage Location Data

Type

Period of

Record

Total Drainage Area Contributing Drainage

Area

mi2 km2 mi2 km2

USGS

05114000

Souris River near

Sherwood, ND Flow 1930-2018 8,940 7,251 3,040 2,466

USGS

05115500

Lake Darling near

Foxholm, ND Elevation 1991-2018 9,450 7,664 3,250 2,636

USFWS Lake Darling near

Foxholm, ND Elevation 1936-1991 9,450 7,664 3,250 2,636

USGS

05116000

Souris River at

Foxholm, ND Flow 1936-2018 9,450 7,664 3,250 2,636

USGS

05116500

Des Lacs River at

Foxholm, ND Flow

1904-06,

1946-2018 939 762 539 437

The elevation record at Lake Darling is irregular. In order to generate a continuous elevation

record at Lake Darling, the interpolate function in HEC DSS-VUE (Reference 2) is used to

approximate missing data points when there are ten or less consecutive days of missing elevation

measurements (see Figure 5). Note that when more than ten consecutive elevation measurements

are missing, it is necessary to approximate inflow to Lake Darling using an alternate approach to

reverse routing. When a significant portion of the elevation record is missing applying linear

interpolation might fail to capture significant increases or decreases in pool. Since the computed

inflow record is derived to reflect these changes in pool elevation, application of reverse routing

would not accurately represent reservoir inflows. Elevation records observed at Lake Darling are

not smoothed prior to carrying out reverse routing.

29

Figure 5. Criteria for Interpolating Between Missing Elevation Measurements

30

5.6.1 Precipitation and Evaporation Data Used

Daily precipitation and evaporation datasets are generated in order to explicitly model the effects

of precipitation and evaporation on the lake surface elevation.

5.6.1.1 Precipitation Data

The U.S Department of Agriculture (USDA) Risk Management Agency and the Norwest

Alliance for Computational Science & Engineering (NACSE), based at Oregon State University,

publish precipitation data gathered from a wide range of monitoring networks to generate spatial

climate datasets published as “PRISM Climate data” (Reference 19). The PRISM, or Parameter-

elevation Relationships on Independent Slopes Model, provides a gridded surface of

precipitation measurements across the United States. Precipitation grids are generated using

factors such as location, elevation, coastal proximity, topographic facet orientation, vertical

atmospheric layer, topographic position and orographic effectiveness of terrain. Continuous,

cumulative, daily PRISM precipitation datasets are available for 1981 to 2018 at the location of

Lake Darling Dam (Latitude: 48.458, Longitude -101.587, approximate location of Foxholm

NCDC gage – see Figure 6Error! Reference source not found.). Continuous, cumulative,

monthly PRISM precipitation datasets are available at the same location for 1896 to 2018.

A daily, precipitation dataset is available from NOAA’s National Climate Data Center (NCDC)

website (https://www.ncdc.noaa.gov) at Lake Darling Dam (Station: USC00323217 Foxholm 7

N, ND US; Latitude: 48.458, Longitude -101.5697 – see Figure 6Error! Reference source not

found.) for the portion of the period of record from 1946 to 2018. However, only about 93% of

the daily record is available. A nearby longer-term, daily precipitation dataset is available at the

Minot Experiment Station, North Dakota (USC00325993, Latitude: 48.1802, Longitude -

101.292963- see Figure 6). Daily precipitation at the Minot Experiment Station is available for

the period of record from 1905 to 2018 (NCDC). Between 1946 and 2018 the Minot Experiment

Station has coverage for 99% of the record.

31

Figure 6. Location of Foxholm 7 N, ND US Precipitation Gage and location of Minot Experiment Station, ND US

Precipitation and Evaporation Gage

The daily, precipitation dataset adopted for this study is developed using both the available,

gridded PRISM data and the point precipitation datasets published by NCDC. For the portion of

the record from 1981 to 2017 the daily data published by PRISM is adopted. For the portion of

the period of record between 1946 and 1981 the temporal distribution of precipitation is captured

using the Foxholm NCDC gage when data is available. When data is unavailable at Foxholm, the

Minot Experiment Station data is directly adopted instead (see example computation Table 15).

No spatial adjustment is necessary due to the close proximity of the two gages (seeError!

Reference source not found. Figure 6). To take advantage of the wide range of monitoring

stations from which the monthly, PRISM dataset draws from, the pre-1981 daily precipitation

dataset generated using the NCDC datasets is adjusted using uniform, monthly multipliers such

that the adopted, total monthly precipitation matches the PRISM monthly totals at the location of

Lake Darling. The difference between the PRISM based monthly, cumulative rainfall and the

monthly rainfall recorded by the point precipitation stations is evenly applied. This methodology

is illustrated in Table 15.

32

Table 15. Development of Precipitation Timeseries

Sample Calculation Precipitation Timeseries

Date (1) (2) (3) (4)

Daily Distribution of Rainfall

ADOPTED Timeseries**

Foxholm, ND

Observed Daily Precipitation

Minot Experiment Station, ND

Observed Daily Precipitation

ADOPTED Temporal Distribution

Data Source:

NCDC NCDC NCDC

Unit: inches mm inches mm inches mm inches mm

6/1/1953 0.00 0.0 0.00 0.0 0.00 0.0 0.00 0.0

6/2/1953 1.69 42.9 0.00 0.0 1.69 42.9 1.31 33.3

6/3/1953 Missing Missing 0.28 7.1 0.28 7.1 0.22 5.6

6/4/1953 Missing Missing 1.75 44.5 1.75 44.5 1.35 34.3

6/5/1953 0.02 0.5 0.00 0.0 0.02 0.5 0.02 0.5

6/6/1953 0.00 0.0 0.00 0.0 0.00 0.0 0.00 0.0

6/7/1953 0.08 2.0 0.07 1.8 0.08 2.0 0.06 1.5

6/8/1953 0.29 7.4 0.15 3.8 0.29 7.4 0.22 5.6

6/9/1953 0.00 0.0 0.00 0.0 0.00 0.0 0.00 0.0

6/10/1953 0.00 0.0 0.00 0.0 0.00 0.0 0.00 0.0

6/11/1953 0.00 0.0 0.00 0.0 0.00 0.0 0.00 0.0

6/12/1953 0.00 0.0 0.00 0.0 0.00 0.0 0.00 0.0

6/13/1953 0.00 0.0 0.00 0.0 0.00 0.0 0.00 0.0

6/14/1953 0.43 10.9 0.07 1.8 0.43 10.9 0.33 8.4

6/15/1953 0.00 0.0 0.00 0.0 0.00 0.0 0.00 0.0

6/16/1953 0.00 0.0 0.00 0.0 0.00 0.0 0.00 0.0

6/17/1953 0.50 12.7 0.90 22.9 0.50 12.7 0.39 9.9

6/18/1953 0.13 3.3 0.00 0.0 0.13 3.3 0.10 2.5

6/19/1953 0.05 1.3 0.10 2.5 0.05 1.3 0.04 1.0

6/20/1953 0.63 16.0 0.41 10.4 0.63 16.0 0.49 12.4

6/21/1953 0.23 5.8 0.04 1.0 0.23 5.8 0.18 4.6

6/22/1953 0.00 0.0 0.00 0.0 0.00 0.0 0.00 0.0

6/23/1953 0.76 19.3 0.49 12.4 0.76 19.3 0.59 15.0

6/24/1953 0.63 16.0 0.80 20.3 0.63 16.0 0.49 12.4

6/25/1953 0.01 0.3 0.00 0.0 0.01 0.3 0.01 0.3

6/26/1953 0.00 0.0 0.00 0.0 0.00 0.0 0.00 0.0

6/27/1953 0.28 7.1 0.12 3.0 0.28 7.1 0.22 5.6

6/28/1953 0.05 1.3 0.14 3.6 0.05 1.3 0.04 1.0

6/29/1953 1.01 25.7 0.15 3.8 1.01 25.7 0.78 19.8

6/30/1953 0.01 0.3 0.00 0.0 0.01 0.3 0.01 0.3

Monthly SUM:

6.80 172.7 5.47 138.9 8.83 224.3 6.83 173.5

PRISM Monthly SUM for JUNE 1953 (cumulative Precipitation inches/mm):

6.83 173.5

Ratio PRISM Monthly Total: NCDC Based Monthly Total: 1.29* * 1.29 = Summation of Column (3) / PRISM Monthly SUM = 8.83/6.83

** Column (4) = Column (3) / 1.29

33

5.6.1.2 Evaporation Data

Evaporation from reservoir surfaces is a significant component of the water balance in the region

which encompasses Lake Darling and the Souris River Basin. Free surface evaporation has a

major impact on how reservoirs are operated. Measured evaporation data is scarce in the study

area.

NCDC publishes an irregular, daily pan evaporation dataset available at the Minot Experiment

station from May 1991 to October 2006. Between 1991 and 2006 evaporation measurements are

only reported 26% of the time. Pan Evaporation data published at the Minot Experiment Station

(adjusted using a pan coefficient of 0.7) was compared to:

Monthly gross evaporation data obtained using the Meyer’s Equation from Agriculture

and Agri-Food Canada at Estevan, Saskatchewan, Williston, North Dakota, Harvey,

North Dakota and Fargo, North Dakota (Reference 15).

Monthly, Pan Evaporation data acquired from NOAA Technical Report NWS 34, Mean

Monthly, Seasonal, and Annual Pan Evaporation for the United States (Reference 16) at

Fargo, North Dakota, Riverdale, North Dakota, and Williston, North Dakota.

Average Annual Gross Evaporation from the Lake Darling Water Control Manual (2012;

Reference 5): 838.2 mm (33 inches).

It was found that the dataset collected at the Minot Experiment Station does not compare well

with other sources of evaporation measurements (see Table 17). Consequently, evaporation data

published by NCDC at Minot Experiment Station is not used as part of this assessment.

Representatives from the USACE, National Weather Service (NWS) and the USFWS are

unaware of any other, more complete evaporation records available in close proximity to Lake

Darling.

In 2002, Agriculture and Agri-Food Canada carried out an analysis of monthly gross evaporation

for 55 locations in the Prairie Provinces and northeastern British Columbia for the time period

1971 to 2000 (see Figure 7; Reference 15). The Meyer’s equation (References 17 and 18) was

used to calculate monthly gross evaporation. To calculate evaporation using the Meyer’s

equation the following datasets are used: monthly mean air temperature, monthly mean vapor

pressure (based on dew point temperature data or relative humidity data), and monthly mean

wind speed. From this analysis a map was generated indicating mean annual gross evaporation

isopleths. These isopleths can be used to estimate gross evaporation from the free water surface

of small to moderate-sized water bodies using spatial interpolation. Subsequent mean annual

gross evaporation maps were published for 1977 to 2006 by the Saskatchewan Watershed

Authority and 1981 to 2010 by Agriculture and Agri-Food Canada. For example, for the 1977 to

2006 map, Isopleths were generated in ArcGIS based on 34 meteorological gage sites where

gross evaporation was approximated by ECCC. Evaporation isopleths were generated by

interpolating the point values into a raster and then generating contours from the raster. Gross

monthly evaporation, calculated using the Meyer’s equation is available for Estevan,

Saskatchewan (Canada) for the period of record from 1946 to 2016.

The 1977 to 2006 and 1981 to 2010 isopleths displayed in Figure 8 and Figure 9 are extended

into the United States (Figure 10). The process described above was applied to extend the

isopleths into the United States, but there are only three sites where evaporation was computed in

34

the United States, so the isopleths south of the U.S/Canadian border should be considered

relatively coarse. Based on the extended isopleths it is determined that evaporation values

computed for Estevan, Saskatchewan are similar in magnitude to what would be computed for

Lake Darling. Thus, monthly gross evaporation measurements at Estevan are adopted for Lake

Darling.

Figure 7. Mean Annual Gross Evaporation (mm) in Saskatchewan: 1971 to 2000

35

Figure 8. Mean Annual Gross Evaporation (mm) for 1977-2006

36

Figure 9. Mean Annual Gross Evaporation (mm) in Saskatchewan: 1981 to 2010

37

Figure 10. Mean Annual Gross Evaporation Isopleths extended to Lake Darling, MN

38

Computed, monthly, cumulative, free surface evaporation values for Estevan, Saskatchewan are

distributed evenly to produce a daily, evaporation timeseries for Lake Darling for 1946 to 2016.

A 30-year average (1987-2016) of computed, monthly, cumulative, free surface evaporation at

Estevan is used to approximate the daily evaporation record at Lake Darling for 2017.

To further verify that using evaporation computed at Estevan provides for a valid approximation

of evaporation at Lake Darling, several comparisons are made. Monthly, cumulative gross

evaporation computed using Meyer’s equation is available at three stations in North Dakota

within the vicinity of Lake Darling: Williston, Harvey and Fargo (see Figure 11). As indicated

within Table 16, gross evaporation computed at Estevan is similar to the gross evaporation

values computed for the North Dakota locations.

Based on the values presented in Table 16 and Table 17, monthly, cumulative gross evaporation

computed at Williston and Fargo using Meyer’s equation (References 17 and 18) can be

compared to monthly, pan evaporation adjusted to be representative of free surface evaporation

using a pan coefficient of 0.77. Pan evaporation data is acquired from NOAA Technical Report

NWS 34, Mean Monthly, Seasonal, and Annual Pan Evaporation for the United States

(Reference 16). Measured, monthly pan evaporation is reported at three locations in North

Dakota, near Lake Darling. When compared to evaporation values estimated using Meyer’s

equation, measured evaporation values are consistently lower. However, computed and measured

evaporation still compare reasonably well. Riverdale, North Dakota is the closest location to

Lake Darling where comparative evaporation data is available (see Figure 11). Class A Pan

Evaporation converted to gross, lake evaporation at Riverdale (Table 17) compares well to

monthly evaporation values computed at Estevan. The Lake Darling Water Control Manual

(2012; Reference 5) states that the average annual gross evaporation in the proximity of Lake

Darling is 838.2 mm (33 inches). This compares well with the annual gross evaporation

computed at Estevan, 906 mm (35.67 inches), using Meyer’s equation.

39

Table 16. Gross Evaporation Comparisons- Meyer’s Equation– Estevan to North Dakota Stations

Location Period of

Record

Units

Evaporation

APR MAY JUNE JULY AUG SEPT OCT TOTAL

Estevan 1946-2016 inches 2.28 5.61 6.27 7.20 7.04 4.86 2.38 35.67

millimeters 57.9 142.5 159.3 182.9 178.8 123.4 60.5 906.0

1961-1987 inches 2.33 5.74 6.73 8.16 7.62 5.06 2.55 38.21

millimeters 59.2 145.8 170.9 207.3 193.5 128.5 64.8 970.5

Williston 1961-1990 inches 2.83 6.54 7.70 9.31 9.22 5.68 2.88 44.29

millimeters 71.9 166.1 195.6 236.5 234.2 144.3 73.2 1125.0

1961-1987 inches 2.77 6.50 7.52 9.18 9.15 5.60 2.83 43.71

millimeters 70.4 165.1 191.0 233.2 232.4 142.2 71.9 1110.2

Harvey 1961-1987 inches 2.92 6.38 8.06 10.26 9.85 6.05 3.13 47.13

millimeters 74.2 162.1 204.7 260.6 250.2 153.7 79.5 1197.1

Fargo 1949-1990 inches 2.54 6.22 6.62 7.41 7.29 5.00 2.59 37.68

millimeters 64.5 158.0 168.1 188.2 185.2 127.0 65.8 957.1

1961-1987 inches 2.49 6.11 6.58 7.39 7.30 4.89 2.48 37.23

millimeters 63.2 155.2 167.1 187.7 185.4 124.2 63.0 945.6

Table 17. Gross Evaporation: Meyer’s Equation (for Estevan) vs. Adjusted ND Class A Pan Evaporation

Location Period of

Record Source Units

Evaporation

MAY JUNE JULY AUG SEPT OCT

Estevan 1946-2016 Meyer’s

Equation

inches 5.61 6.27 7.20 7.04 4.86 2.38

millimeters 142.5 159.3 182.9 178.8 123.4 60.5

Fargo WSO AP 1963-1979 NOAA TR

NWS 34

inches 5.58 5.95 6.83 5.98 4.13 3.08

millimeters 141.7 151.1 173.5 151.9 104.9 78.2

Riverdale 1949-1979 NOAA TR

NWS 34

inches 5.63 6.01 7.00 6.69 4.64 3.20

millimeters 143.0 152.7 177.8 169.9 117.9 81.3

Williston 1956-1979 NOAA TR

NWS 34

inches 5.41 6.08 7.19 6.98 4.37 3.08

millimeters 137.4 154.4 182.6 177.3 111.0 78.2

Minot

Experiment

Station (NOT

USED)

1991-2006 NCDC

inches 3.16 3.00 3.73 3.57 2.50

millimeters 80.3 76.2 94.7 90.7 63.5

40

Figure 11. Evaporation Reference sites

5.6.2 Consumptive & Water Supply Usages Downstream of Lake Darling

No direct water usages occur from Lake Darling’s pool so no direct loses are modeled or

accounted for in the reverse routing used to generate the inflow record to Lake Darling. Water

use that occurs downstream of Lake Darling and was considered in HEC-ResSim model

development (see HH6 model report). Within the study area, significant water usages, defined as

appropriations that exceed 6,167 dam3/year (5,000 acre-feet/year), occur to meet the water

supply needs of the Minot municipal and rural water systems and the Eaton Irrigation District.

Water use permits are issued and the requestor of the permit can take less than the permit

amount, but not more. Records of observed water usage are not available to use in this modeling

effort. The water systems at Minot are permitted for 18,500 dam3 (15,000 acre-feet) per year;

however, records of significant water use have not been recorded to date. The Eaton Irrigation

District withdraws about 15,400 dam3 (12,500 acre-feet) per year for flood irrigation near

Towner, ND. It is estimated that approximately 40% of the volume of water removed by the

Eaton Irrigation District project is returned to the Souris River Basin.

Flow diversions are included in ResSim to model consumptive water use at Minot and between

Towner, ND (Towner) and Bantry, ND (Bantry) as part of Eaton Irrigation. When modeling

historical flows, consumptive use is implicitly accounted for within the local flows computed as

part of the HH1 dataset. Thus, the diversion relationships are defined as zero when using HH1

41

products as model inputs. When datasets produced using precipitation-runoff models, stochastic

hydrology, or climate changed traces are used in the ResSim model, the Eaton Irrigation water

use is modeled explicitly using a timeseries along with a 40% return flow rate.

5.6.3 Reverse Routing – Mass Balance Analysis: Lake Darling Inflows

Inflows to Lake Darling are computed using reverse routing. The following mass balance

equation is applied to convert reservoir outflows, pool elevations, precipitation inputs, and

evaporation outputs to reservoir inflows:

Inflow = Change in Storage + Outflow + Evaporative Losses – Precipitation on the Pool

Change in storage is converted from change in elevation using the Lake Darling elevation

capacity curve. Evaporative losses and precipitation on the pool is available in inches. These

values are converted to volumetric measurements using the Lake Darling elevation-area-capacity

curve. The elevation-area-capacity curve adopted for this analysis is based upon 1998

bathymetric survey data up to elevation 1594 feet NGVD 29. A LiDAR based elevation-area-

capacity relationship is adopted for pool elevations above 1595 feet NGVD 29. The adopted

elevation-area-capacity relationship is displayed in Table 18.

42

Table 18. Lake Darling Elevation-Area-Capacity Curve

Elevation-Area-Capacity Curve: Lake Darling Reservoir

Source: 1998 Bathymetric Survey Data Source: LiDAR Data

Elevation

(NGVD 29) Area Storage

Elevation


Elevation


feet meters acre km2 acre-feet dam3 feet meters acre km2 acre-feet dam3 feet meters acre km2 acre-feet dam3

1574.00 479.76 10 0.04 0 0 1595.08 486.18 9,605 38.89 90,611 111,723 1601.97 488.28 12,199 49.39 166,087 204,785

1575.00 480.06 31 0.13 20 25 1595.4 486.28 9,705 39.29 93,789 115,642 1602.29 488.38 12,322 49.89 170,131 209,772

1576.00 480.36 53 0.21 62 76 1595.73 486.38 9,751 39.48 96,989 119,587 1602.62 488.48 12,429 50.32 174,214 214,806

1577.00 480.67 110 0.45 144 178 1596.06 486.48 9,855 39.90 100,221 123,572 1602.95 488.58 12,540 50.77 178,337 219,890

1578.00 480.97 168 0.68 282 348 1596.39 486.58 9,932 40.21 103,496 127,611 1603.28 488.68 12,665 51.28 182,532 225,062

1579.00 481.28 310 1.26 519 640 1596.72 486.68 10,003 40.50 106,796 131,679 1603.61 488.78 12,756 51.64 186,707 230,210

1580.00 481.58 455 1.84 896 1,105 1597.05 486.78 10,183 41.23 110,234 135,919 1603.94 488.88 12,849 52.02 190,923 235,408

1581.00 481.89 1,524 6.17 1,873 2,309 1597.37 486.88 10,272 41.59 113,599 140,068 1604.26 488.98 12,966 52.49 195,177 240,653

1582.00 482.19 2,600 10.53 3,908 4,819 1597.7 486.98 10,391 42.07 117,005 144,267 1604.59 489.08 13,115 53.10 199,502 245,986

1583.00 482.50 3,525 14.27 6,924 8,537 1598.03 487.08 10,520 42.59 120,448 148,512 1604.92 489.18 13,229 53.56 203,836 251,330

1584.00 482.80 4,449 18.01 10,844 13,371 1598.36 487.18 10,731 43.45 124,002 152,894 1605.25 489.28 13,340 54.01 208,211 256,724

1585.00 483.11 5,024 20.34 15,494 19,104 1598.69 487.28 10,904 44.15 127,614 157,348

1586.00 483.41 5,595 22.65 20,701 25,524 1599.01 487.38 11,121 45.02 131,308 161,903

1587.00 483.72 6,027 24.40 26,396 32,546 1599.34 487.48 11,250 45.55 134,992 166,445

1588.00 484.02 6,458 26.15 32,509 40,084 1599.67 487.58 11,354 45.97 138,706 171,024

1589.00 484.33 7,181 29.07 39,188 48,319 1600 487.68 11,497 46.55 142,494 175,695

1590.00 484.63 7,905 32.00 46,577 57,429 1600.33 487.78 11,632 47.09 146,382 180,489

1591.00 484.94 8,334 33.74 54,530 67,235 1600.65 487.88 11,741 47.53 150,225 185,227

1592.00 485.24 8,763 35.48 62,897 77,552 1600.98 487.98 11,837 47.92 154,104 190,010

1593.00 485.55 9,082 36.77 71,623 88,311 1601.31 488.08 12,012 48.63 158,132 194,977

1594.00 485.85 9,416 38.12 80,649 99,440 1601.64 488.18 12,107 49.02 162,094 199,862

43

5.6.4 Routing Method: Lake Darling Inflows

Because the elevation record at Lake Darling is incomplete, an alternate method is adopted to

generate inflows for portions of the period of record where there are greater than ten consecutive

days of missing pool elevation measurements. This method consists of routing flows recorded at

USGS gage 05114000, Souris River near Sherwood, North Dakota to the upstream extent of

Lake Darling reservoir. Muskingum routing (K = 29 hours, X = 0.36, 1 subreach) is used to route

the Sherwood hydrograph downstream. The routed Sherwood hydrograph is combined with an

approximation of the local flow hydrograph between Sherwood and Lake Darling. An

approximation of the local flow hydrograph is determined based on applying a drainage area

ratio of 0.39 (see Table 19) to the observed streamflow hydrograph recorded on the Des Lacs

River at Foxholm, North Dakota (USGS gage 05116500). There are a series of eight

impoundments along the Des Lacs River upstream of the Foxholm, North Dakota gage used to

approximate the local flow contribution from the unregulated drainage area between Sherwood

and Lake Darling. However, the low gradient of the Des Lacs River compounded with the small

size and inconsistent elevations of the Des Lacs water control structures limits water

management capacity. Thus, it is reasonable to assume that the flow response between Sherwood

and Lake Darling is similar to the flow response at the Foxholm USGS gage on the Des Lacs

River.

Table 19. Drainage Area Analysis Sherwood to Lake Darling

USGS Gage

Number Gage Location

Total Drainage Area Contributing Drainage Area

mi2 km2 mi2 km2

USGS 05114000 Souris River near Sherwood, ND 8,940 23,155 3,040 7,874

USGS 05115500 Lake Darling near Foxholm, ND 9,450 24,476 3,250 8,418

Sherwood to Lake Darling- Intervening Drainage Area: 510 1,321 210 544

USGS 05116500 Des Lacs River at Foxholm, ND 939 2,432 539 1,396

Drainage Area Ratio: 0.39

Comparisons of the inflow record to Lake Darling generated using reverse routing versus the

approximation of local flows and routing method are displayed in Figure 12, Figure 13, and

Figure 14.

44

Figure 12. 1948 Lake Darling Inflows- Reverse Routed (Blue) & Routed (Sherwood + Local Flows; red)

45


46


47

5.6.5 HEC-ResSim Verification of Lake Darling Inflows

HEC-ResSim (Reference 4) is used to verify that the reverse routed inflows are computed

correctly by inputting the Lake Darling inflow record computed using reverse routing into HEC-

ResSim and specifying that Lake Darling Reservoir releases flows equivalent to the observed

outflow record at USGS 05116000 Souris River at Foxholm, North Dakota. Releases are

specified using the release override function within HEC-ResSim’s simulation module. If

inflows are computed correctly, modeled pool elevation outputs should be nearly equivalent to

observed elevations recorded by the U.S Fish and Wildlife Service and at USGS Gage 05115500,

Lake Darling Reservoir near Foxholm, North Dakota. Figure 15 and Figure 16 demonstrate that

the mass balance seems to be reasonably satisfied for Lake Darling when computed inflows are

adopted. As can be seen in Figure 16, as the model is run for an extended period the computed

elevations begin to deviate slightly from the observed elevation record. This is due to rounding

and to the approximation of elevations and inflows for portions of the period of record where

elevation data is unavailable for Lake Darling. These small differences get compounded as the

time window being model is extended. As can be seen in Figure 17, when a subset of the longer

record displayed in Figure 16 is modeled, the modeled record once again matches the observed

record.

48

Figure 15. Reverse Routing Verification 1967-1970

49


50


51

The daily precipitation and evaporation timeseries are inputted into HEC-ResSim within the

reservoir editor as the evaporation timeseries. To include the effects of precipitation on the pool the

daily precipitation timeseries is subtracted from the daily evaporation timeseries and the resulting

difference hyetograph is inputted into HEC-ResSim. Sample computations are displayed in Table

20 and

Figure 18Figure 18.

Table 20. Computation of NET: Evaporation – Precipitation Timeseries

Souris River Basin: Lake Darling

Source: NCDC/PRISM Meyer's Equation: Estevan, Sask. Computed

Data Type: Daily Total Precipitation Daily Total Evaporation Daily Total NET Precipitation/

Evaporation

Date in mm in mm in mm

01May1978 0.000 0.0 0.155 3.9 0.155 3.9

02May1978 0.000 0.0 0.155 3.9 0.155 3.9

03May1978 0.000 0.0 0.155 3.9 0.155 3.9

04May1978 0.000 0.0 0.155 3.9 0.155 3.9

05May1978 0.091 2.3 0.155 3.9 0.064 1.6

52

06May1978 0.155 3.9 0.155 3.9 0.000 0.0

07May1978 0.200 5.1 0.155 3.9 -0.045 -1.1

08May1978 1.046 26.6 0.155 3.9 -0.891 -22.6

09May1978 0.000 0.0 0.155 3.9 0.155 3.9

10May1978 0.100 2.5 0.155 3.9 0.055 1.4

11May1978 0.046 1.2 0.155 3.9 0.109 2.8

12May1978 0.737 18.7 0.155 3.9 -0.582 -14.8

13May1978 0.082 2.1 0.155 3.9 0.073 1.9

14May1978 0.000 0.0 0.155 3.9 0.155 3.9

15May1978 0.000 0.0 0.155 3.9 0.155 3.9

16May1978 0.000 0.0 0.155 3.9 0.155 3.9

17May1978 0.000 0.0 0.155 3.9 0.155 3.9

Figure 18. Computation of NET: Evaporation – Precipitation Timeseries

5.6.6 Local Flow Hydrograph: Sherwood, North Dakota to Lake Darling

53

There are three options for computing the local flow hydrograph between flows recorded at USGS

gage 05114000, Souris River near Sherwood, North Dakota to the upstream extent of Lake Darling

reservoir.

Option 1: The first option is to approximate local flow by applying a drainage area ratio of

0.39 (see Table 19) to the observed streamflow hydrograph recorded on the Des Lacs River

at Foxholm, North Dakota (USGS gage 05116500).

Option 2: The second option is to route the observed streamflow hydrograph recorded at

USGS gage 051140000, Souris River near Sherwood, North Dakota to the upstream extent

of Lake Darling and subtract the routed hydrograph from the computed inflow hydrograph

for Lake Darling derived using reverse reservoir routing. The resulting difference

hydrograph is representative of local flow between Sherwood and Lake Darling.

Option 3: The third option is to develop a hybrid inflow hydrograph to Lake Darling that

takes into account the inflow hydrographs developed using both reverse routing and the

drainage area ratio/ routed Sherwood flows approach. This hybrid hydrograph is then

subtracted from the routed observed, Sherwood, North Dakota hydrograph to generate the

local flow hydrograph between Sherwood and Lake Darling.

Within the HH6 ResSim model runs for the period of record and to evaluate proposed changes to

the operating plan Option 2 is adopted. This option is selected because it best satisfies the mass

balance for Lake Darling Reservoir.

6. Summary of 1930 – 1945 Extension

In order to evaluate the impact of changes to the operating plan on the 1930s drought, the period of

record used to evaluate changes to the operating plan has been adopted as 1930 to 2017. The 2013

Regional and Reconstructed Hydrology Study (Attachment 1) only covered the period of record

from 1946 to 2012. Consequently, the streamflow records had to be back extended to 1930.

6.1 Saskatchewan 1930 — 1945 Record Extension

There is limited observed, streamflow data available within the Souris River Basin, pre-1946. A

combination of estimated and observed datasets are used to define flow timeseries at critical

locations, reservoir inflow hydrographs and local flow hydrographs for the Saskatchewan portion

of the Souris River Basin, covering the drainage area upstream of Sherwood, North Dakota.

6.1.1 Active Gage Sites 1930 – 1945

Five hydrometric stations located between the headwaters of the Souris River and Sherwood, North

Dakota recorded flows between 1930 and 1945 (Table 21). Four of the five stations provide

relatively good coverage throughout this time period: Souris River near Estevan, Saskatchewan

(05NB007), Souris River near Sherwoogd (05ND007), Moose Mountain Creek near Oxbow,

Saskatchewan (05ND004) and Long Creek near Estevan, Saskatchewan (05NB001). There are

gaps in the records at Souris River near Estevan, Saskatchewan (05NB007) and Long Creek near

Estevan, Saskatchewan (05NB001) from 1924 to 1932, and in the Moose Mountain Creek near

54

Oxbow, Saskatchewan (05ND004) record from 1918 to 1932. The fifth station that recorded flows

during this period of time is the Souris River near Oxbow, Saskatchewan (05ND003), which is

missing data from 1931 to 1942. Table 21. Summary of the active hydrometric stations in Saskatchewan for the period 1930 – 1945

Hydrometric

Station Name Time Period Missing Data

05NB007 Souris River near Estevan 1911-1970 1924-1932; 1956-1965

05NB001 Long Creek near Estevan 1911-Present 1924-1932; 1958

05ND003 Souris River near Oxbow 1928-1970 1931-1942

05ND004 Moose Mountain Creek near

Oxbow 1913-Present 1918-1932

05ND007 Souris River near Sherwood 1930-Present 2012

6.1.2 1930 – 1945 Souris Headwaters Gage (Estevan) & Tributary Inflow Record Extension

The missing data in the records at the Souris River near Estevan station (headwaters gage) and

tributary gages along Long Creek and Moose Mountain Creek are filled in using two different

approaches: Maintenance of Variance Extension Type 1 method (MOVE.1; Reference 10), and a

Flow Duration Curve based approach (FDC, Reference 11). The two different techniques are

applied using recorded flows at the Souris River near Sherwood, North Dakota hydrometric station

(05ND007) as the long-term reference station. The MOVE.1 and the FDC methods were previously

used to fill and extend data in the Souris River Basin as part of the Regional and Reconstructed

Hydrology analysis (2013; Attachment 1).

The Long Creek near Estevan record is extended back to 1930 using the FDC approach, applied

using the Souris River near Sherwood record. The period of record between 1933 and 1957 is used

to develop the FDC relationship. Both the Long Creek near Estevan and Sherwood gages are

operational during this period and the flows are not yet impacted by Boundary Reservoir. Boundary

Reservoir became fully operational in 1958. Moose Mountain Creek near Oxbow records are

extended back to 1930 using the FDC approach with the Souris River near Sherwood record. The

period of record between 1933 and 1991 is used to develop the FDC relationship. Both gages were

operational during this portion of the period of record and flows were not yet being impacted by

Rafferty and Grant Devine Reservoirs (it is assumed that Boundary does not have a significant

impact on flows at Sherwood because of the small size of Boundary Reservoir). Souris River near

Estevan records are extended back to 1930 using the MOVE.1 approach. The Souris River near

Sherwood gage is used to develop the MOVE.1 relationship using the period of record between

1933 and 1955 (no data is available at Estevan between 1956 and 1958). Neither Rafferty

Reservoir nor Boundary Reservoir were operational prior to 1958.

The estimated tributary timeseries are adjusted for travel times which are obtained using cross-

correlation analysis. The suitability/skill of the two different techniques used to reconstruct flows is

evaluated by using the Nash-Sutcliffe (NSE) coefficient, summarized in Table 22. Table 22. Nash-Sutcliffe coefficients – Sherwood, ND is long-term station

55

Hydrometric Station Nash-Sutcliffe (NSE)

MOVE.1 Flow Duration Curve (FDC)

Long Creek near Estevan (05NB001)

Period 1933-1957

0.71*

Souris River near Estevan (05NB007)

Period 1933-1955

0.86* -

Moose Mountain Creek near Oxbow (05ND004)

Period 1933-1991

0.59*

*Adopted results

The MOVE.1 approach performs poorly when reconstructing observed records at Moose Mountain

Creek near Oxbow in terms of NSE, therefore, flows are reconstructed using the FDC approach

that provided better results in terms of NSE (0.59 for the period 1933 to 1991). Figure 19 illustrates

a comparison of the reconstructed and recorded flows at Long Creek near Estevan for a portion of

the period of record when the gage was active and Figure 20 illustrates the final adopted flows at

this hydrometric station. The final adopted flow record is a combination of the reconstructed flows

and the observed flows.

56

Figure 19. Estimated (Flow Duration Curve Method) vs Observed Flows - Long Creek near Estevan

57

Figure 20. Long Creek near Estevan- Adopted flows.

Flows at the Souris River near Estevan hydrometric station (05NB007) are reconstructed using the

MOVE.1 approach. The MOVE.1 relationship is developed using the observed record at Sherwood

and the period of record for which both the Estevan and Sherwood gages were operational: 1933 to

1955 period. A comparison of reconstructed flows to observed flows for their concurrent period of

record is illustrated in Figure 21. Figure 22 illustrates the adopted flow record for 1930 to 1945.

The adopted flow record is a combination of the reconstructed flows and observed records. The

Souris River near Estevan flows are used to calculate inflows into Rafferty Reservoir and local

flows between the headwater’s reservoirs and Sherwood.

58

Figure 21. Observed vs. Estimate Flows Souris River near Estevan

59

Figure 22. Adopted flows for the Souris River near Estevan

Flows are estimated at the Moose Mountain Creek near Oxbow hydrometric stations (05ND004)

using the FDC approach applied using the Souris River near Sherwood record as the long-term

station. The FDC relationship is based on data collected between 1933 and 1991 (prior to the

construction of Grant Devine and Rafferty). A comparison of observed versus approximated flows

for Moose Mountain Creek is displayed in Figure 23 for 1933 to 1991. The NSE obtained when

observed flows at the Moose Mountain Creek gage are compared to the computed flows is 0.59.

Figure 24 illustrates the adopted record for the period 1930 to 1945. The adopted record consists of

a combination of observed flows, where available, and estimated flows.

60

Figure 23. Observed vs estimated flows for Moose Mountain Creek near Oxbow

61

9 Figure 24. Adopted flows for Moose Mountain Creek near Oxbow

6.1.3 1930 – 1945 Raffegrty Inflows

Once the missing data for the Souris River near Estevan (05NB007) and Long Creek near Estevan

(05NB001) hydrometric stations are filled in, inflows to Rafferty are estimated as the positive

difference of the two flows (equation 1). This approach is consistent with the approach used to

estimate Rafferty inflows for the period 1946 to 1970 in the Reconstructed Hydrology Report

(2013; Attachment 1). No additional adjustments are made to the records because the drainage area

between Rafferty Dam and the two hydrometric stations is considered negligible (90.6 km2 [35

mi2], based on the 2013 Reconstructed Hydrology Report/ 75.1 km2 [29 mi2] based on the updated

drainage areas provided in Table 23). Figure 25 illustrates estimated inflows to Rafferty Reservoir

for the period 1930 to 1945.

Q RafIn (t) = Q 05NB007 (t) – Q 05NB001 (t) (Equation 1)

62

Figure 25. Estimated inflows to Rafferty Reservoir for the period 1930 – 1945

6.1.4 1930 – 1945 Boundary Inflows

Boundary Reservoir inflows are assumed to be equal to the flows at Long Creek near Estevan

hydrometric station for the period of record between 1930 and 1945. Boundary Dam was not

constructed until 1958.

Q Boundary in (t) = Q 05NB001 (t) (Equation 2)

6.1.5 1930 – 1945 Grant Devine Inflows

Grant Devine (GD) inflows for the period of record between 1930 and 1945 are estimated to be

equal to the flows observed at the Moose Mountain Creek near Oxbow hydrometric station

(05ND004).

Q GDIn (t) = Q 05ND004 (t) (Equation 3)

6.1.6 1930 – 1945 Local Flow Estimation

Local flows are calculated by computing the difference between the routed and adopted flows at

critical locations during 1930 to 1945 period (holdout method). A portion of the HEC- ResSim

model for the Souris River (HH6) is used to hydrologically route flows from the Souris River at

63

Estevan and Moose Mountain Creek near Oxbow gage sites to Sherwood, North Dakota (Figure

26). For the routing reaches between Estevan and Sherwood the Modified Puls technique is

applied to route flows. These local flow records are applied within the HH6 HEC-ResSim model

to produce “with project” and “state of nature” continuous flow timeseries along the mainstem of

the Souris River at the following critical flow locations: Estevan, Roche Percee, Oxbow, Glen

Ewen and Sherwood.

Figure 26. ResSim Network utilized to calculate the local flows for the period 1930 – 1945

The total local flow hydrograph is distributed using drainage area ratios. Drainage area ratios are

defined using the ratio between local drainage areas of interest and the total drainage area

between the Souris River near Estevan, Moose Mountain Creek near Oxbow, and Sherwood hydrometric stations (Table 23). Note the drainage areas used for this analysis are obtained from

the data harmonization project within the International Watershed Initiative from the

International Joint Commission (Reference 12). These drainage areas differ from the drainage

areas reported in the USACE 2013 Regional and Reconstructed Hydrology Study (Attachment

1), although the differences in drainage area between the two products have a negligible impact

on results. Table 23 shows the drainage areas utilized in the 2013 study as well as the updated

drainage areas used in this analysis.

64

Table 23. Local drainage areas between Souris River - Estevan and Souris River - Sherwood

Drainage Areas (D.A.)

USACE 2013 Effective

Drainage Area

Updated Effective Drainage

Area (km2)

km2 mi2 km2 mi2

Total Drainage Area: From the

Reservoirs to Estevan (Local 0) 90 35 74 29

Estevan to Roche Percee

without Short Creek (D.A. u1) 105 41 103 40

Roche Percee to Oxbow (D.A.

u2) 430 166 432 167

Oxbow to Glen Ewen (D.A. u3) 100 39 88 34

Glen Ewen to Sherwood (D.A.

u4) 220 85 226 87

Short Creek (D.A. sc) 325 125 329 127

Total Drainage Area: Estevan

to Sherwood 1,180 456 1,178 455

6.1.6.1 Methodology for 1930, 1943 – 1945

The total local flow contributing to the Souris River between Estevan and Oxbow for 1930 and

between 1943 and 1945 is estimated by routing the observed flows for the Souris River at

Estevan and for Moose Mountain Creek near Oxbow downstream and subtracting the routed

flows from the flows recorded by the Souris River gage near Oxbow (Equation 4).

Total Local Q (t) = Q 05ND003 (t) – Q Routed (Equation 4)

The local flows between Estevan and Roche Percee (LF1) are initially obtained by applying a

drainage ratio and a travel time of 2 days (eq. 5) to the total local flow hydrograph computed for

the area between Estevan and Oxbow. The Short Creek local flows (LFsc) and the local flow

between Roche Percee and Oxbow (LF2) are also initially calculated using drainage area ratios

(see Equations 6 and 7). A travel time of 2 days is assumed for the flow contributions from Short

Creek.

Estevan to Roche Percee:

LF1 (t) = (DA u1 / DAT1-2) * Total Local Q (t-2) (Equation 5)

Short Creek:

LFsc = (DA sc / DAT1-2) * Total Local Q (t-2) (Equation 6)

Roche Percee to Oxbow:

LF2 (t) = DA u2 /DA T1- 2 * Total Local Q (t) (equation 7)

65

Where, DA u1 is the local drainage area between Estevan and Roche Perce (excluding Short

Creek, 103 km2 [39.7 mi2]), DA Sc is the Short Creek drainage area (329 km2 [127 mi2]), DA

T1-2 is the total local drainage area between Estevan and Oxbow plus Short Creek drainage area

(864 km2 [333.5 mi2]) and DA u2 is the local drainage area between Roche Percee and Oxbow

(432 km2 [166.7 mi2]).

The total local flow hydrograph between Oxbow and Sherwood is estimated as the difference

between the routed, observed Oxbow flows and the recorded flows at Sherwood (Equation 8).

Local Q 1 (t) = Q 05ND007 (t) – Q Routed (t) (Equation 8)

Local flows between Oxbow and Glen Ewen are estimated using a drainage area ratio and a

travel time of one-day (Equation 9).

Oxbow to Glen Ewen: LF3 (t) = (DA u3 /DA T3-4) * Local Q 1 (t-1) (Equation 9)

Where, DA u3 is the local drainage area between Oxbow and Glen Ewen (88 km2 [33.9 mi2])

and DA T3-4 is the total local drainage area between Oxbow and Sherwood (314 km2 [121.2

mi2]).

Local flows between Glen Ewen and Sherwood are estimated using equation 10.

Glen Ewen to Sherwood: LF4 (t) = (DA u4 / DA T3-4) * Local 1 (t) (Equation 10)

Where, DA u4 is the local drainage area between Glen Ewen and Sherwood (226 km2 [87.2

mi2]). 6.1.6.2 Methodology for 1931 – 1942

For the period 1931 to 1942 local flows are estimated by calculating the difference between the

routed flows from the gaged, Souris River at Estevan site and Moose Mountain Creek near

Oxbow site, and recorded flows at Sherwood (Equation 11). Then the local flows for the

different intervening drainage areas are distributed according to drainage area and estimated

travel times (Equations 12 to 16).

Total LocalB (t) = Q 05ND007 (t) – Q Routed (t) (Equation 11)

Estevan to Roche Percee (excluding Short Creek):

LF1 (t) = (DA u1 / DA Total) * LocalB (t-4) (Equation 12).

Note that the total local flow hydrograph is first lagged four days to account for travel time

between Roche Percee and Sherwood.

Short Creek:

LFSC = (DA sc / DA Total) * LocalB (t-4) (Equation 13)

Note that the total local flow hydrograph is first lagged four days to account for travel time

66

between the confluence of Short Creek with the Souris River and Sherwood.

Roche Percee to Oxbow (excluding Moose Mountain Creek):

LF2 (t) = (DA u2 / DA Total) * LocalB (t-2) (Equation 14)

Note that the total local flow hydrograph is first lagged two days to account for travel time

between Oxbow and Sherwood.

Oxbow to Glen Ewen:

LF3 (t) = (DA u3 / DA Total) * LocalB (t-1) (Equation 15)

Note that the total local flow hydrograph is first lagged one-day to account for travel time

between Glen Ewen and Sherwood.

Glen Ewen to Sherwood:

LF4 (t) = (DA u4 / DA Total) * LocalB (t) (Equation 16)

6.1.6.3 Local Flow Verification

In general, the process described in the section above is an iterative process in which the flows at

the different insertion points are adjusted based on drainage areas until the routed flows match

the observed flows at Oxbow and Sherwood for the period 1930 to 1945.

Figure 27 illustrate the routing network utilized to verify the flows.

67

Figure 28 and Figure 29 illustrate a comparison of the simulated and observed flows at Souris

River near Oxbow for the period 1943 to 1945 and Souris River near Sherwood for the period

1930 to 1945, respectively.

Figure 27. Routing Network: Souris River near Estevan to Souris River near Sherwood for 1930 – 1945

68

Figure 28. Observed flows versus ResSim output for the Souris River near Oxbow

69

Figure 29. Observed flows versus ResSim output for the Souris River near Sherwood

6.2 North Dakota Record 1930 – 1946 Extension

Streamflow records for the Souris River and its tributaries located between Sherwood, North

Dakota and Westhope, North Dakota are extended from 1930 to 1945, where necessary, at the

locations shown in Figure 30.

70

Figure 30. Streamflow estimation points: Sherwood to Westhope

Streamflow records and local flow records for the portion of the Souris River between Sherwood

and Westhope had to be extended back to 1930. Where observed data is unavailable, several

different streamflow approximation techniques are applied to fill-in the datasets required.

Maintenance of Variance Extension Type 1 (MOVE.1; Reference 10) and Flow Duration Curve

analyses (FDC; Reference 11) methods are used to estimate the missing data. This is consistent

with the method applied as part of the USACE 2013 Regional and Reconstructed Hydrology

Study (Attachment 1).

The long-term, mainstem stations at Minot and Sherwood are used to extend and fill-in records

using the portion of the period of record recorded prior to the construction of Rafferty and Grant

Devine Dams (1930-1991). In addition to the stations listed above, one station upstream of

Sherwood is also used to support record extension. Flows recorded at the Moose Mountain Creek

station near Oxbow (05ND004) prior to the construction of Grant Devine Dam in 1991 are used

to estimate tributary flow.

Locations where local flow estimates are required within the ResSim model are listed in Table

24 and indicated by the red circles with a white halo in Figure 31.

71

Table 24. Locations Requiring Flow Approximation: Sherwood to Westhope

River Location Station Id Period of Missing Data

Souris River Sherwood 05ND007/05114000 01/01/ 1930 - 03/11/1930

Souris River Above Lake Darling Inflow to Lake Darling 01/01/1930 – 12/31/1945

Souris River Burlington Confluence Des Lacs 01/01/1930 – 12/31/1945

Souris River Near Velva Velva 01/01/1930 – 12/31/1945

Souris River Verendrye 05120000 01/01/1930 - 04/01/1937

Souris River Bantry 05122000 01/01/1930 - 03/01/1937

Souris River US Dam 320 US Dam 320 01/01/1930 – 12/31/1945



Souris River Westhope 05124000 01/01/1930 - 04/01/1930

Des Lacs River Foxholm 05116500 01/01/1930 - 10/01/1945

Wintering River Karlsruhe 05120500 01-01/1930 - 03/01/1937

Willow Creek Willow City 05123400 01/01/1930 – 12/31/1945

Boundary Creek Landa 05123900 01/01/1930 – 12/31/1945

Cut bank Creek Upham 05123750 01/01/1930 – 12/31/1945

Stone Creek Kramer 05123500 01/01/1930 – 12/31/1945

Deep River Upham 05123510 01/01/1930 – 12/31/1945

72

Figure 31. Computation nodes requiring streamflow inputs

73

6.2.1 Relevant Streamflow Gages (Active & Inactive)

There are six gaging stations located along the mainstem of the Souris River between Sherwood

and Westhope in North Dakota. These are: Sherwood, Foxholm, Minot, Verendrye, Bantry and

Westhope. The USGS Station above Minot has the longest record and started recording

streamflow data in 1903. The USGS stations at Sherwood and Westhope started recording flow

in March 1930 and April 1930, respectively. The USGS gage located near Verendrye began

reporting flows in April 1937 and the Souris River gage at Bantry began recording in March

1937. The USGS gaging station located along the Souris River at Foxholm started reporting

flows in October 1936 after the construction of Lake Darling Dam. There is also data available

for the tributaries that feed into the Souris River system between Sherwood and Westhope. Some

of the tributary stations were in operation for few years and then subsequently terminated, while

others are still in operation. A list of gaging stations located along the mainstem of the Souris

River and its tributaries between Sherwood and Westhope, along with their respective operating

periods is given in Table 25.

Table 25. List of gage stations with data periods

River Location Station ID Period of Data Available Period of Missing data

Souris River Sherwood 05ND007/05114000 03/11/1930 - current

Souris River Foxholm 05116000 10/01/1936 - current

Souris River Above

Minot

05117500 05/01/1903 - current

Souris River Verendrye 05120000 04/01/1937 - current

Souris River Bantry 05122000 03/01/1937 - current

Souris River Westhope 05124000 08/01/1929 -current 11/01/1929 –

03/31/1930

Des Lacs River Foxholm 05116500 07/01/1904 - current 09/30/1906 - 09/30/1945

Wintering River Karlsruhe 05120500 03/01/1937 – current

Willow Creek Willow City 05123400 09/01/1956 - current

Boundary Creek Landa 05123900 10/01/1957- 09/29/2000

Cut Bank Creek Upham 05123750 10/01/1974 –

09/30/2000

Stone Creek Kramer 05123500 03/01/1986 - 09/30/2000

Deep River Upham 05123510 10/01/1957 - current

6.2.2 1930 – 1945 Mainstem Souris River – Approximation of Flow

6.2.2.1 Streamflow at Sherwood

The Souris River at Sherwood gage started recording flow on March 11, 1930 (ECCC database).

Flows between January 1st and March 10th of 1930 are assumed to be zero.

6.2.2.2 Inflow to Lake Darling,

74

To estimate inflow to Lake Darling, Souris River flows at Sherwood are used. The MOVE.1

technique is applied to generate an approximation of inflows to Lake Darling Reservoir from

1930 to 1945. Prior to applying MOVE.1 a log transform is applied to the recorded flows at

Sherwood. Flows are lagged by one-day to represent the travel time from Sherwood to Lake

Darling. When compared to the inflow record to Lake Darling adopted for the period of record

between 1946 and 2017, flows approximated using the MOVE.1 technique produce consistent

results with a NSE value of 0.97, Figure 32.

Figure 32. Current estimation and prior reconstructed data of Lake Darling inflow

75

6.2.2.3 Streamflow at station above Minot

The USGS gaging station above Minot, North Dakota has been in continuous operation since

May 1, 1903. There are no data gaps in the record (Figure 33).

Figure 33. Souris River flow at USGS station above Minot

6.2.2.4 Souris River flow at Verendrye and Bantry

Gaging stations on the Souris River at Verendrye and Bantry started recording flows on April 1,

1937 and March 1, 1937, respectively. River flows from 1930 to 1937 are estimated at both sites

using the MOVE.1 method and the Minot gage as a long-term index station. A log transform is

applied to the data prior to generating the MOVE.1 relationship. The MOVE.1 relationship is

derived using the period of record where the Verendrye, Bantry and Minot gages were active:

1937-present. A comparison is made between observed streamflow data at Verendrye and Bantry

to streamflow values computed using MOVE.1. NSE values are given in Table 26 and plots of

estimated versus observed values are given in Figure 34 for Verendrye and in Figure 35 for

Bantry.

76

Table 26. NSE Values of estimated and observed flows

River Index Station Partially-gaged Station Method NSE value

Souris River Sherwood Lake Darling MOVE.1 0.97

Souris River Minot Verendrye MOVE.1 0.84

Souris River Minot Bantry MOVE.1 0.82

77

Figure 34. Comparison of Observed vs. Estimate Flows (MOVE.1) at Verendrye.

78

Figure 35. Comparison of Observed vs. Estimate Flows (MOVE.1) at Bantry.

79

6.2.3 1930 – 1945 Approximation of Tributary Contributions

Due to data scarcity, estimation of flow for the tributaries between Sherwood and Westhope is

very challenging. Various methods and index stations had to be assessed to arrive at reasonable

techniques for approximating tributary flows. Table 27 illustrates the various methods and index

stations considered for approximating flows along the Des Lacs River. A similar process is

applied to select a record extension technique for the other tributaries that reach their confluence

with the Souris River between Sherwood and Westhope, North Dakota.

Table 27. Methods used for flow estimation of the Des Lacs River

River Index station Method used NSE value

Des Lacs River

Moose Mountain Creek FDC -0.08

Souris at Sherwood FDC -0.17

Souris above Minot MOVE.1 Log Transform -0.79

Moose Mountain Creek MOVE.1 -1.26

Moose Mountain Creek MOVE.1 Log Transform -1.79

Souris above Minot FDC 0.26

6.2.3.1 Des Lacs River and Wintering River Flows

The following methods are evaluated to estimate flow contributions from the Des Lacs River and

Wintering River Tributaries:

FDC with Moose Mountain Creek

FDC with the Souris River at Sherwood

FDC with the Souris River at Minot

MOVE.1 with Souris River at Sherwood

MOVE.1 with Moose Mountain Creek

MOVE.1 with the Souris River at Minot

For the Wintering River, the best results are obtained by applying MOVE.1 using the Souris

River at Sherwood as an index station. Prior to applying MOVE.1 a log transform is applied to

Sherwood flows. As indicated in Figure 36, if flows recorded along the Wintering River are

linearly compared to concurrent observations at Sherwood R= 0.7 (R2 = 0.52). This implies that

using a regression based approach is reasonable. A comparison of observed flows recorded on

the Wintering River to estimated flows is displayed in Figure 37.

80

Figure 36. Correlation of Souris at Sherwood and Wintering at Karlsruhe

81

Figure 37. Wintering River-Comparison of Observed vs. Estimate Flows (MOVE.1)

The Des Lacs River streamflow record is back extended using the FDC technique and the

streamflow record recorded along the Souris River at Minot. The NS coefficient is 0.26 and a

comparison of observed versus approximated flows along the Des Lacs is displayed in Figure 38.

82

Figure 38. Observed and estimate flows at Des Lacs River at Foxholm hydrometric station (NS= 0.26).

6.2.3.2 Willow Creek

Willow Creek flows are extended using the flow duration curve (FDC) technique and the

adopted Moose Mountain Creek flows. Flows estimated at Willow Creek are lagged one-day in

order to account for the timing difference between Moose Mountain and Willow Creek. The

timing difference is estimated based on a cross-correlation analysis. A comparison of estimated

flows to observed flows resulted in a Nash-Sutcliffe (NS) coefficient of 0.51. Figure 39

illustrates a comparison of the estimated and observed flows for Willow Creek.

83

Figure 39. Reconstructed and observed flows at Willow Creek using the FDC approach.

6.2.3.3 Cut Bank Creek

Cut Bank Creek flows are extended by using the flow duration curve (FDC) technique and the

adopted Moose Mountain Creek flows. Flows estimated at Cut Bank Creek are lagged six days in

order to account for the timing difference between Cut Bank Creek and Moose Mountain Creek.

The timing difference is estimated based on a cross-correlation analysis. The reconstructed flows

at Cut Bank Creek result in a Nash-Sutcliffe coefficient of 0.32. Figure 40 illustrates a

comparison of the approximated and observed flows for Cut Bank Creek.

84

Figure 40. Reconstructed and observed flows at Cut Bank Creek

6.2.3.4 Deep River

Deep River flows are extended using the flow duration curve (FDC) technique and the adopted

Moose Mountain Creek record. Flows estimated along the Deep River are lagged one-day in

order to account for the timing difference between the flow response along the Deep River and

Moose Mountain Creek. The timing difference is estimated based on a cross-correlation analysis.

The reconstructed flows for Deep River result in a Nash-Sutcliffe coefficient of 0.31. Figure 41

illustrates a comparison of the estimated and observed flows for Deep River.

85

Figure 41. Reconstructed and observed flow at Deep River using the FDC approach

6.2.3.5 Stone Creek

Streamflow records for Stone Creek are approximated by applying the MOVE.1 technique and

the adopted flows for Boundary Creek. This approach is consistent with the approach taken as

part of the 2013 USACE Regional and Reconstructed Hydrology Report (Attachment 1). The

MOVE.1 technique is applied for the portion of the period of record where the Stone Creek gage

was active and results in a Nash-Sutcliffe coefficient of 0.77. Figure 42 illustrates the

reconstructed flows for Stone Creek compared to observed flows.

86

Figure 42. Reconstructed and observed flows at Stone Creek using the MOVE.1 approach.

6.2.3.6 Boundary Creek

Initially, Boundary Creek flows are approximated using the flow duration technique (FDC) using

Moose Mountain Creek as index station. This resulted in a poor Nash-Sutcliffe (NS) coefficient

of 0.07. Due to the poor NS obtained by using the FDC approach, Boundary Creek flows are

estimated using a drainage area ratio (Reference 2) and the adopted flows for Deep River. This

approach is consistent with the technique applied as part of the 2013 USACE Regional

Reconstructed Hydrology Report (Attachment 1). Flows at Boundary Creek are lagged two days

in order to account for the difference in timing. The drainage area approach used to estimate

flows at Boundary Creek results in a Nash Sutcliffe (NS) coefficient of 0.55. Figure 43 illustrates

the observed and estimated flows at Boundary Creek.

87

Figure 43. Estimated and Observed flows at Boundary Creek.

Table 28 summarizes the methods applied to reconstruct flows between 1930 and 1945 for

tributary sites located between Sherwood and Westhope. Table 28 also displays the Nash

Sutcliffe (NS) coefficients associated with the adopted technique.

88

Table 28. NSE value of Observed and Simulated streamflow of tributaries

River Index Station Partially-gaged Station Method used NSE

value

Boundary Creek Deep River- Upham, ND Boundary Creek - Landa, ND Drainage Area

Ratio 0.55

Deep River Moose Mountain Creek -

Oxbow, Sask. Deep River - Upham, ND FDC 0.31

Des Lacs River Souris - Minot, ND Des Lacs River - Foxholm, ND FDC 0.26

Willow Creek Moose Mountain Creek-

Oxbow, Sask.

Willow Creek - Willow City,

ND FDC 0.51

Wintering River Souris River - Sherwood, ND Wintering River - Karlsruhe,

ND

MOVE.1 with

Log Transform 0.29

Cut Bank Moose Mountain Creek -

Oxbow, Sask. Cut Bank Creek - Upham, ND FDC 0.32

Stone Creek Boundary Creek - Landa, ND Stone Creek - Kramer MOVE.1 0.77

6.2.4 1930 – 1945 Local Flow Estimation

Local flows are computed by finding the difference between flows routed from an upstream node

to a downstream station and the adopted flow record at the downstream station. The resulting

total local flow hydrograph is then distributed to the sub-sections of the basin between the

upstream and downstream nodes along the mainstem of the Souris River. Distributed local flows

are then routed from their respective locations to the downstream node and compared to the

observed flow record at that site. Local flows are then adjusted through iteratively until the

routed and observed flow match reasonably well. The local flow computation also offsets error

incurred during estimation of tributaries flows.

6.2.4.1 Flow from Sherwood to Lake Darling inflow from 1930 – 1945

Local flows from Sherwood to Lake Darling are computed by routing Souris River flows from

Sherwood to Lake Darling using the hydrologic routing relationship defined within the HH6

HEC-ResSim model and subtracting routed flow from the adopted flow record at the Lake

Darling inflow node. A plot of the adopted flow record at Lake Darling versus the flow record at

Lake Darling estimated by routing the adopted record at Sherwood and combining with an

approximation of local flow is displayed in Figure 44. As can be seen from the plot the two flow

records are nearly identical.

89

Figure 44. Adopted vs Routed Flow at Lake Darling

90

6.2.4.2 Local Flow from Lake Darling/Foxholm to Minot (1930 – 1936)

Local flows that reach the Souris River between Lake Darling and the Des Lacs River at

Foxholm, North Dakota are determined by routing the adopted flows at Lake Darling to Minot

using the hydrologic routing relationships in the HH6 HEC-ResSim model. Routed flows are

subtracted from observed flow record at Minot to estimate total local flow. The total local flow

hydrograph is then distributed by drainage area according to the ratios presented in Table 29.

Table 29. Drainage Area Ratios- from Lake Darling to Minot

River Location Contributing Drainage Area Drainage Area

Ratio mi2 km2

Souris

River

Lake Darling to Des Lacs

confluence*

26.1 67.6 0.182

Des Lacs

River

Foxholm gage to Burlington 106.6 276.1 0.745

Souris

River

Des Lacs Confluence to Minot 10.4 26.9 0.073

* Note that when calculating Lake Darling Inflows, the drainage area between the Lake Darling inflow point and the Souris

River at Foxholm, ND USGE gage is assumed to be negligible. This is also assumed during the local flow calculation for

consistency.

After initially distributing local flows based on drainage area, adopted Lake Darling Inflows are

routed and combined with the initial approximations of local flow. The resulting streamflow

record at Minot is compared to the observed streamflow record at Minot. Local flows are then

iteratively adjusted and re-routed and combined until the reconstructed flows and observed flows

at Minot are as close as possible. A comparison of computed and observed flow at Minot is

displayed in Figure 45.

91

Figure 45. Observed and Reconstructed flow of the Souris River at Minot (1930 -1936)

6.2.4.3 Local Flow from Lake Darling/Foxholm to Minot (1937 – 1945)

The USGS gage located along the Souris River at Foxholm, North Dakota started recording flow

after completion of Lake Darling Dam in 1936. Thus, post-1936 local flow between Foxholm

and Minot is computed by finding the difference of the routed, observed flow record from the

Souris River at Foxholm gage to Minot and the observed flow record at Minot. Then the total

local flow hydrograph is distributed between three sub-drainage areas according to Table 30.

After initially distributing local flows based on drainage area, observed flows at the USGS gage

located along the Souris River at Foxholm are routed downstream and combined with the initial

approximations of local flow. The resulting streamflow record at Minot is compared to the

observed streamflow record at Minot. Local flows are then iteratively adjusted and re-routed and

combined until the reconstructed flows and observed flows at Minot are as close as possible (see

Figure 46).

92

Table 30. Distribution of Local Flow from Foxholm to Minot


Ratio mi2 km2

Souris River USGS gage at Foxholm, ND to

Des Lacs River confluence 26.1 67.6 0.182

Des Lacs

River

USGS gage at Foxholm, ND to

Burlington, ND 106.6 276.1 0.745

Souris River Des Lacs River confluence to

USGS gage at Minot, ND 10.4 26.9 0.073

Figure 46. Observed and Reconstructed flow of the Souris River at Minot (1937 - 1945)

93

6.2.4.4 Local Flow from Minot to Verendrye from 1930 – 1945

Flow at Minot is routed to Verendrye using the routing defined by the HH6 HEC-ResSim model

and compared with the adopted flow record at Verendrye. Total local flow is computed by

subtracting routed flow from the adopted flows. Total local flow is then distributed according to

drainage area using the ratios defined in Table 31. Local flows are then iteratively adjusted and

re-routed and combined until the reconstructed flows and observed flows at Verendrye are as

close as possible (Figure 47).

Table 31. Drainage Area Distribution: Minot to Verendrye


Ratio mi2 km2

Souris River USGS gage at Minot to USGS gage at Velva 430 1114 0.86

Souris River USGS Velva to USGS gage at Verendrye 70 181 0.14

Figure 47. Observed and Reconstructed flow of the Souris River at Verendrye (1930 - 1945)

94

To compute the local flow record from Verendrye to Bantry, Souris River flows at Verendrye are

routed downstream to Bantry using the routing parameters defined within the HH6 HEC-ResSim

model. Routed flows are combined with the adopted streamflow record for the Wintering River.

The local flow hydrograph is defined as the difference between the routed flows at Bantry and

observed flow at Bantry. There is an insignificant amount of ungaged, contributing drainage area

between Verendrye and Bantry (excluding the drainage area captured by the Wintering River

gage). Historically, the only time there was significant local flow was in 2011. However, local

flow is approximated and included as an input when defining the flow record between 1930 and

1945 to offset any errors generated by estimating Wintering River flows. Pre-1937 Wintering

River flows must be estimated. There is not a lot of tributary gage data available in the vicinity

pre-1937, thus there is a lot of uncertainty and potential error associated with estimated

Wintering River flows. There is a lot more confidence in the estimates of flow along the

mainstem because there are several, nearby long-term mainstem gages. Thus, an error correction

is made at the mainstem station at Bantry, downstream of the Wintering River confluence. This

correction is made to adjust for some of the error introduced by approximating flows along the

Wintering River. A comparison of observed and estimated Souris River flow at Bantry is given

in Figure 48.

Figure 48. Observed and Reconstructed flow of the Souris River at Bantry (1930 - 1945)

95

The J. Clark Salyer structures were built in 1935. Therefore, local flows are computed separately

prior to construction (1930 – 1935) and post construction (1936 – 1945).

Local flow from Bantry to Westhope between 1930 and 1935 is calculated by routing adopted

flows at Bantry, North Dakota downstream and subtracting estimated flow from observed flow at

Westhope. Flow is then distributed according the drainage area ratios in Table 32.

Table 32. Total ungaged local flow from Bantry to Westhope

Flow Location Local flow Contributing Drainage Area Drainage Area

Ratio mi2 km2

Local Flow 1 Dam 320 Bantry to Dam 320 540 1,399 0.40

Local Flow 2 Dam 332 Dam 320 to Dam 332 335 868 0.25

Local Flow 3 Dam 341 Dam 332 to Dam 341 100 259 0.07

Local Flow 4 Dam 357/Westhope Dam 341 to Dam 357 370 958 0.28

96

A comparison of estimated and observed flows at Westhope, North Dakota is displayed in Figure

49.


6.2.4.5 Local Flow from Bantry to Westhope 1936 – 1945

In order to calculate local flows during this period of time, it is assumed that all the J. Clark

Salyer structures were established and completed by the end of water year 1935. Therefore, local

flows between Bantry and Westhope are estimated using drainage area ratios applied to the

adopted flows for the Deep River tributary. This is the same method that was applied as part of

the USACE 2013 Regional and Reconstructed Hydrology analysis (Attachment 1). Table 33

summarizes the drainage areas for the tributaries, the ungaged local drainage areas and the

overall drainage area ratio with Deep River. The total ungaged local area flow is distributed

according to the ratios provided in Table 32.

97

Table 33. Drainage area analysis Bantry to Westhope and Drainage Area Ratios with Deep River

Pertinent Drainage Areas between Bantry, ND and Westhope, ND

Period of Record


mi2 km2 mi2 km2

Souris River near Bantry, ND 1937-Active 12,300 31,857 4,700 12,173

Willow Creek near Willow City 1956-Active 1,160 3,004 730 1,891

Deep River near Upham 1957-Active 975 2,525 370 958

Cut Bank Creek at Upham 1974-2000 722 1,870 272 704

Stone Creek near Kramer* 1986-2000 168 435 671 1,738

Boundary Creek near Landa 1957-2000 230 595 170 440

Souris River near Westhope, ND 1939-Active 16,900 43,771 6,600 17,094

Total Intervening Drainage Area 1,900 4,921

Total Unaccounted for Intervening Drainage Area 291 754

Ungaged Local Area Drainage Area Ratio with Deep River 0.79 * The Contributing Drainage area for Stone Creek near Kramer was estimated based on the assumption that only 40% of

the drainage area contributes flow. This was consistent with the percentage of contributing drainage area within the Deep

River watershed and the overall contributing drainage area reported at Bantry and Westhope.

To check to make sure results are reasonable, the estimated local flows between Bantry and

Westhope are used as inputs to the HH6 HEC-ResSim model from 1936 to 1945. As mentioned

previously, it is assumed that all the J. Clark Salyer structures were completed in 1935, therefore,

the structures are assumed to be near empty at the beginning of the simulation (lookback

elevations as of Jan 1st 1935 are set to the invert elevations for all the structures). Two

simulations are carried out. The first simulation is from 1936 to 1939. For this initial simulation

period look back elevations for the refuge structures are set to be equal to their invert elevations

and no minimum flow rule is applied for Westhope. The second simulated period is from 1936 to

1945. For this second simulation, lookback elevations are assumed to be equivalent to guide

curve elevations and the 0.56 m3/s (20 ft3/s) minimum rule at Westhope is maintained. Simulated

flows at Westhope for both periods of time are compared to observed flows in Figure 50.

There are significant differences between simulated and recorded flows at Westhope. The

differences in flows are likely due to a number of factors that include the assumptions made to

carry out this simulation (i.e. all the structures in place and completed in 1935, starting water

levels in the different structures, operations, etc.) and the reconstructed data sets. As indicated by

the low Nash Sutcliffe coefficients computed in the previous sections, there is a large amount of

uncertainty in the flows estimated for the tributaries that reach their confluence with the Souris

between Bantry and Westhope. Between 1930 and 1945 there is not a lot of gaged data available

within the basin.

98


6.3 Summary of 2012 – 2017 Extension

To build on the analysis completed for the 2013 Regional and Reconstructed Hydrology Study

(Attachment 1), homogenous, continuous daily timeseries datasets representative of reservoir

inflows, local flow hydrographs, and tributary inflows are developed for the period from 2012

through 2017. These datasets, when combined with the existing 1946 to 2013 timeseries and the

back-extended 1930 to 1945 timeseries, make up a reconstructed hydrologic record of the Souris

River basin spanning the period of record used for the Plan of Study.

6.3.1 Products

Table 34 below describes each continuous daily flow timeseries estimated for the 2012 to 2017

extension.

99

Table 34. Timeseries Estimated for 2012-2017 Extension

Station ID

Description Period of

Recorded Data Estimation Technique

Other Gage Record(s) Used For Analysis

5123900 BOUNDARY CREEK NEAR LANDA 1957-2000 MOVE.3 DEEP RIVER NEAR UPHAM

5123750 CUT BANK CREEK AT UPHAM 1974-2000 Flow Duration & General Relations

DEEP RIVER NEAR UPHAM

- INFLOW TO BOUNDARY RESERVOIR - Reverse Routing

LONG CREEK NEAR ESTEVAN, BOUNDARY

DIVERSION

- INFLOW TO GRANT DEVINE RESERVOIR - Reverse Routing

MOOSE MOUNTAIN CREEK NEAR OXBOW

- INFLOW TO LAKE DARLING RESERVOIR - HEC-ResSim Routing

-

- INFLOW TO RAFFERTY RESERVOIR - Reverse Routing

SOURIS RIVER BELOW RAFFERTY RESERVOIR, BOUNDARY DIVERSION

05ND004 MOOSE MOUNTAIN CREEK NEAR OXBOW 1933-2014 Appended Nearby Records

MOOSE MOUNTAIN CREEK BELOW GRANT

DEVINE LAKE

05NB007 SOURIS RIVER NEAR ESTEVAN 1911-1970 HEC-ResSim Routing

-

05ND001 SOURIS RIVER NEAR GLEN EWEN 1970-1994 HEC-ResSim Routing

-

05ND003 SOURIS RIVER NEAR OXBOW 1928-1970 HEC-ResSim Routing

-

05NB009 SOURIS RIVER NEAR ROCHE PERCEE 1956-1995 HEC-ResSim Routing

-

- SOURIS RIVER NEAR VELVA - HEC-ResSim Routing

-

5123500 STONE CREEK NEAR KRAMER 1986-2000 MOVE.3 BOUNDARY CREEK NEAR LANDA

Local flow hydrographs are also estimated along the mainstem Souris and Des Lacs Rivers for

2012 to 2017. These local flows, listed in Table 35 below, are used as inputs to the HH6 HEC-

ResSim routing model used in this analysis as well as the HEC-ResSim model developed for the

Plan of Study.

100

Table 35. Local Flow Timeseries Estimated for 2012-2017 Extension

River Description Contributing Drainage Area

Estimation Technique mi2 km2

Souris River RESEVOIRS TO ROCHE PERCEE 76 196.8 HEC-ResSim Routing

Souris River ROCHE PERCEE TO OXBOW 166 429.9 HEC-ResSim Routing

Souris River OXBOW TO GLEN EWEN 39 101.0 HEC-ResSim Routing

Souris River GLEN EWEN TO SHERWOOD 85 220.2 HEC-ResSim Routing

Souris River SHERWOOD TO LAKE DARLING 210 543.9 General Relations

Des Lacs River FOXHOLM TO BURLINGTON 106.6 276.1 HEC-ResSim Routing

Souris River FOXHOLM TO DES LACS CONFLUENCE 26.1 67.6 HEC-ResSim Routing

Souris River DES LACS CONFLUENCE TO MINOT 10.4 26.9 HEC-ResSim Routing

Souris River MINOT TO VELVA 430 1,113.7 HEC-ResSim Routing

Souris River VELVA TO VERENDRYE 70 181.3 HEC-ResSim Routing

Souris River BANTRY TO DAM 320/326 540 1,398.6 HEC-ResSim Routing

Souris River DAM 320/326 TO DAM 332 335 867.7 HEC-ResSim Routing

Souris River DAM 332 TO DAM 341 100 259.0 HEC-ResSim Routing

Souris River DAM 341 TO DAM 357/WESTHOPE 370 958.3 HEC-ResSim Routing

6.3.2 Data Sources

Data sources used in this analysis include streamflow and stage gages operated by the U.S.

Geological Survey (USGS) and Environment and Climate Change Canada (ECCC), as well as

evaporation data collected by the National Oceanic and Atmospheric Administration (NOAA)

and the Saskatchewan Water Security Agency (SWSA). All stream gages used to produce the

daily timeseries datasets displayed in Section 6.3.1 are listed in Appendix A and displayed as

part of the topology diagram and map included as Appendices A and B. The gage nomenclature,

period of record, location, and drainage area information presented in Appendix A was compiled

from the USGS Nation Water Information System, “Water Data for the Nation (Reference 7),”

and the Government of Canada’s Water Level and Flow database (Reference 9) as part of the

USACE 2013 Regional and Reconstructed Hydrology Study.

101

6.3.3 Methodology

The methodology used to extend each daily timeseries for the period 2012 to 2017 consists of

MOVE.3 (Reference 10), a flow-duration algorithm (Reference 11), drainage area transfer

(general relations; Reference 2), reservoir reverse routing (mass balance approach), and

hydrologic routing. These methods are consistent with the methodology employed in the USACE

2013 Regional and Reconstructed Hydrology Study, save MOVE.3, which is used instead of

MOVE.1 was used in 2013. The following sections detail how daily flow timeseries are

estimated for each reach.

6.3.4 2012 – 2017 Canadian Dams to Sherwood, ND

Between 2012 and 2017 there are four active streamflow gages, four inactive streamflow gages,

and one partial gage record from the Canadian reservoirs (Rafferty, Boundary, and Grant

Devine) to the international crossing at Sherwood, North Dakota, as shown in

Figure 51.

Figure 51. Rafferty Reservoir to Sherwood Schematic

For this analysis, the following daily flow timeseries are estimated:

Souris River near Estevan, SK

Local flow between Estevan, SK and Roche Percee, SK

Souris River near Roche Percee, SK

Local flow between Roche Percee, SK and Oxbow, SK

Moose Mountain Creek near Oxbow, SK (Partial)

Souris River near Oxbow, SK

Local flow between Oxbow, SK and Glen Ewen, SK

Souris River near Glen Ewen, SK

Local flow between Glen Ewen, SK and Sherwood, ND

Long Creek-

Estevan

Sherwood

Roche

Percee –

Data Gap

1965-

Moose Mountain Creek- Oxbow

Short Creek-Roche

Percee

Rafferty

Reservoir

Oxbo

w

Souris River

Glen Ewen

Estevan

Key

No gage data

Gaged

Partial record

Junction

Direct Routing

Mod Puls

Local flow

102

6.3.4.1 Hydrologic Routing

The HH6 HEC-ResSim hydrologic routing model is used to develop local flow hydrographs

from the Canadian reservoirs to Sherwood, North Dakota between 2012 and 2017. To ensure

homogeneity with local flow hydrographs developed from 1946 to 2013 as part of the 2013

Regional and Reconstructed Hydrology Study (Attachment 1), the same methodology and

hydrologic routing parameters are used.

As described in further detail in Section 6 of the 2013 Regional and Reconstructed Hydrology

Study report in Attachment 1, Modified Puls routing parameters were developed in 2013 using a

calibrated unsteady HEC-RAS model of the Souris River between Rafferty Reservoir and

Sherwood, North Dakota and were calibrated utilizing 0.5, 0.75, 1, 1.25, 1.5, and 2 times the

2011 event. The adopted routing parameters are shown in Table 36. Corresponding storage-

discharge relationships can be found in Section 6 of the 2013 Regional and Reconstructed

Hydrology Study report.

Table 36. Rafferty Reservoir to Sherwood Routing Parameters

Reach Routing Method

Subreach Parameter Channel Slope

ft/mi m/km

Souris River: Rafferty Reservoir to Estevan Null Routing 1 0.96 0.18

Souris River: Estevan to Roche Percee Modified Puls Routing

1 1.38 0.26

Souris River: Roche Percee to Upstream of Moose Mountain Creek

Modified Puls Routing

<0.75 x 2011: 6

>0.75 x 2011: 2

0.87 0.16

Souris River: Oxbow to Glen Ewen Modified Puls Routing

1 1.26 0.24

Souris River Glen Ewen to Sherwood Crossing

Modified Puls Routing

2 1.24 0.23

6.3.4.2 Local Flow Estimation

Local flows from the Canadian reservoirs to Sherwood, North Dakota are estimated using the

hydrologic routing parameters from the HH6 HEC-ResSim model. The routing model is

developed by modifying the existing HEC-ResSim model (v. 3.1) for the Souris River from the

Canadian reservoirs to Minot, North Dakota. The model is modified by removing Rafferty,

Boundary, and Grant Devine (formerly Alameda) reservoirs, resulting in the network shown in

Figure 52.

103

Figure 52. HEC-ResSim Routing Model Network – Rafferty Reservoir to Sherwood

After the reservoirs are removed, the routing model is run for the 2012 to 2017 time period using

observed outflows from Rafferty, Boundary, and Grant Devine reservoirs and observed flows at

Short Creek near Roche Percee, Saskatchewan as inputs to the “Input Rafferty,” “Input

Boundary,” “Input Alameda,” and “Short Creek at Roche Percee” nodes, respectively, and no

local flows at any intermediate node. The selected alternative is “Natural Fl,” and the selected

simulation is “LF Raff-Sherw 10-17.”

These model inputs yield a computed flow hydrograph at Sherwood which includes no upstream

local flow contributions. To generate a total local flow hydrograph representative of all local

flows above Sherwood, the computed flow hydrograph at Sherwood is subtracted from the

observed hydrograph at Sherwood. Then, to compute the local flow contributions to each reach,

the resulting flow hydrograph is multiplied by each reach’s corresponding drainage area ratio

and lagged, as shown in Table 37.

Table 37. Rafferty Reservoir to Sherwood Local Flow Reach Parameters

Local Flow Reach Contributing Drainage Area Drainage Area

Ratio Lag

(days) mi2 km2

Reservoirs to Roche Percee 76 197 0.21 4

Roche Percee to Oxbow 166 430 0.45 3

Oxbow to Glen Ewen 39 101 0.11 1

Glen Ewen to Sherwood 85 220 0.23 0

104

Pertinent drainage areas are shown in

Table 38 for each local flow reach. Note the intervening drainage area from Rafferty and

Boundary reservoirs to Estevan is considered negligible and is added to the contributing drainage

area from Estevan to Roche Percee during the drainage area ratio computation.

Table 38. Rafferty Reservoir to Sherwood Drainage Areas

Gage Description Contributing Drainage Area

mi2 km2

1. Souris River below Rafferty Reservoir , SK 969 2,510

2. Long Creek near Estevan, SK 575 1,489

3. Souris River near Estevan, SK 1,579 4,090

Intervening Drainage Area Reservoirs to Estevan 35 91

4. Souris River near Roche Percee, SK 1,745 4,520

5. Short Creek near Roche Percee, SK 125 324

Intervening Drainage Area Estevan to Roche Percee 41 106

6. Moose Mountain Creek nr Oxbow, SK 838 2,170

7. Souris River at Oxbow, SK 2,749 7,120

Intervening D.A Roche Percee to just U/S MMCRK 166 430

8. Souris River at Glen Ewen, SK 2,788 7,221

Intervening D.A Oxbow to Glen Ewen 39 101

9. Souris River at Sherwood, ND 2,873* 7,441

Intervening D.A Glen Ewen to Sherwood 85 220 *This value is the most current estimate published by ECCC as of July 2018. The USGS estimate is slightly higher (3,040

square miles, or 7,874 square kilometers).

After each local flow from the Canadian reservoirs to Sherwood is computed, the local flows are

added to the HEC-ResSim model, and the model is recomputed. Then, to further improve the

estimate of each local flow hydrograph, the difference between the routed and observed

hydrograph at Sherwood, North Dakota is minimized by iteratively distributing the difference

between the routed and observed hydrographs utilizing the same drainage area ratios and lags

shown in Table 37. Figure 53 and Figure 54 show the resulting modeled and observed discharges

at Sherwood for the years 2013 and 2014, respectively.

105

Figure 53. Observed vs. Modeled Discharge - Sherwood, 2013

Nash-Sutcliffe

Coefficient = 0.999

106

Figure 54. Observed vs. Modeled Discharge - Sherwood, 2014

6.3.4.3 Record Extension

There is no gage data from 2012 to 2017 at the Souris River near Estevan, Roche Percee, Glen

Ewen, and Oxbow, and the Moose Mountain Creek near Oxbow, Saskatchewan gage was only

recording from 2012 to 2014. Records at these sites are estimated for the period 2012 to 2017

using hydrologic routing.

Moose Mountain Creek near Oxbow, SK

The Moose Mountain Creek near Oxbow, Saskatchewan gage is operated by ECCC and records

outflow from Grant Devine Reservoir. This gage was discontinued in 2014. A new streamflow

gage labelled Moose Mountain Creek below Grant Devine Lake (ENVCA 05ND013) started

recording Grant Devine outflows in 2015 and has a continuous period of record to the present

day. Since this gage is less than 3.2 km (2 miles) upstream of the discontinued site, the Moose

Mountain Creek below Grant Devine Lake record is directly appended to the Moose Mountain

Creek near Oxbow record using null routing to create a continuous record of Grant Devine

Reservoir outflows from 2012 to 2017. Several short gaps of one, two, five, and 16 days exist in

the Moose Mountain Creek near Oxbow gage in 2014 with the largest gap occurring in February.

Since these gaps are small and do not occur at critical points in the year, the linear interpolation

function in HEC-DSSVue is used to fill in the gaps and generate a continuous flow record.

107

Souris River near Estevan, Roche Percee, Glen Ewen, and Oxbow, SK

The HH6 HEC-ResSim model is used to compute local flows by hydrologically routing flows

from the Canadian reservoirs to Estevan, Roche Percee, Glen Ewen and Oxbow. Refer to Section

6.3.4.1 for the hydrologic routing parameters used in the model. While there is no gage data at

any of these sites to compare to, the modeled discharge correlates very well with observed

discharge at Sherwood, as shown in Figure 53 and Figure 54 above.

6.3.5 2012 – 2017 Sherwood, ND to Minot, ND

There are four active streamflow gages from Sherwood, North Dakota to Minot, North Dakota,

all of which have a continuous record from 2012 to 2017. The gage at the Des Lacs River at

Burlington has a continuous record from 2012 to 2017, but it records river stage only. These

gages are shown in Figure 55 below.

Figure 55. Sherwood to Minot Schematic

For this analysis, the following daily flow timeseries are estimated:

Local flow between Sherwood, ND and Lake Darling

Local flow between the Souris River near Foxholm, ND and the Souris-Des Lacs

confluence

Local flow between the Des Lacs River at Foxholm, ND and the Souris-Des Lacs

confluence

Local flow between the Souris-Des Lacs confluence and Minot, ND


The H6 HEC-ResSim hydrologic routing parameters are used to develop local flow hydrographs

from Lake Darling to Minot, North Dakota between 2012 and 2017. To ensure homogeneity with

local flow hydrographs developed from 1946 to 2013 as part of the 2013 Regional and

Reconstructed Hydrology Study, this analysis adopts the routing parameters and contributing

drainage areas identified as part of the Des Lacs River HEC-HMS model developed by West

Consultants, Inc.


Local flows from Sherwood, North Dakota to Minot, North Dakota are estimated using two

different techniques, general relations methodology and the hydrologic routing based holdout

method.

Des Lacs River-

Burlington Des Lacs River-

Foxholm

Sherwood Minot

Souris River

Foxholm

Lake Darling

Key

Ungaged

Gaged

Junction

Direct Routing

Mod Puls

Local flow

Reservoir

108

Sherwood to Lake Darling

To maintain homogeneity with the 2013 Regional and Reconstructed Hydrology (Attachment 1),

general relations methodology is used to estimate the local flow contributions from Sherwood,

North Dakota to Lake Darling. General relations methodology is based on the assumption that a

flow hydrograph representative of a hydrologically similar drainage area can be transferred to an

ungaged location utilizing a drainage area ratio (Reference 2). As described in Section 6.2.5 of

the 2013 Regional and Reconstructed Hydrology Report, Attachment 1, the drainage area

captured by the Des Lacs River at Foxholm, North Dakota gage (USGS 05116500) is most

hydrologically similar to the local drainage area between Sherwood and Lake Darling. Therefore,

to estimate the local flow from Sherwood to Lake Darling, flows recorded at the Des Lacs River

at Foxholm gage are multiplied by 0.39, the drainage area ratio between the two locations, as

shown in Table 39.

Table 39. Sherwood to Lake Darling Drainage Areas

Location Contributing Drainage Area

mi2 km2

Souris River near Sherwood, ND USGS 05114000 3,040* 7,874

Local Runoff Reach: Sherwood to Lake Darling 210 544

Lake Darling near Foxholm, ND, USGS 05115500 3,250 8,418

Des Lacs River at Foxholm, ND USGS 05116500 539 1,396

Drainage Area Ratio: 0.39

*This value is the current, updated USGS estimate of contributing Drainage Area.

Lake Darling Outlet to Minot, ND

Local flows from Lake Darling Reservoir to Minot, North Dakota are estimated using the HH6

hydrologic routing model within HEC-ResSim. The routing model is developed by modifying

the existing HEC-ResSim model from the Canadian reservoirs to Minot, North Dakota

(Reference 4). The model is modified by removing all network elements upstream of and

including Lake Darling, resulting in the network shown in Figure 56.

109

Figure 56. HEC-ResSim Routing Model Network – Lake Darling to Minot

After the upstream elements are removed, the routing model is run for the 2012 to 2017 time

period using observed outflows from Lake Darling Reservoir as inputs to the “Foxholm Souris”

node, observed inputs on the Des Lacs at Foxholm and no intermediate local flows. The selected

alternative is “LFFoxtoMin,” and the selected simulation is “LF FoxtoMinot 10-17.”

These model inputs yield a computed flow hydrograph at Minot with no upstream local flow

contributions. To generate a flow hydrograph representative of all ungagged local flows above

Minot, below the gage on the Des Lacs and below Lake Darling, the computed flow hydrograph

at Minot is subtracted from the observed hydrograph at Minot. Then, to compute the local flow

contributions of each reach, the resulting flow hydrograph is multiplied by each reach’s

corresponding drainage area ratio and lagged, as shown in Table 40. Then, to further improve the

estimate of each local flow hydrograph, the difference between the routed and observed

hydrograph at Minot, North Dakota is minimized by iteratively distributing the difference

between the routed and observed hydrographs utilizing the same drainage area ratios and lags

shown below.

Table 40. Lake Darling to Minot Local Flow Reach Parameters

Local Flow Reach Contributing Drainage Area Drainage

Area Ratio Lag

(Days) mi2 km2

Foxholm (Souris) to Souris-Des Lacs Confluence 26.1 67.5 0.18 0

Foxholm (Des Lacs) to Souris-Des Lacs Confluence 106.6 276.1 0.74 1

Souris-Des Lacs Confluence to Minot 10.4 26.9 0.073 0

110

Figure 57 and Figure 58 show the resulting modeled and observed discharges at Minot for the

years 2013 and 2014, respectively.

Figure 57. Observed vs. Modeled Discharge – Minot, 2013

111

Figure 58. Observed vs. Modeled Discharge - Minot, 2014

6.3.6 2012 – 2017 Minot, ND to Bantry, ND

The Wintering River is the major tributary to the Souris River between Minot, North Dakota and

Bantry, North Dakota. The Wintering River reaches its confluence with the Souris downstream

of Verendrye, North Dakota. Bonnes Coulee, which enters the Souris River just upstream of

Velva, North Dakota, is a dry run that can significantly contribute to mainstem flow during flood

events. The only streamflow data available for Bonnes Coulee is an annual maximum peak flow

record (intermittently record from 1965 to 2017). The 137 km2 (53 mi2) contributing drainage

area associated with Bonnes Coulee is small, and the average recorded annual maximum is only

approximately 9.3 m3/s (330 ft3/s). Consequently, Bonnes Coulee is not explicitly modeled as

part of this analysis.

Figure 59 below shows a schematic of the Souris River from Minot to Bantry, and Table 41 lists

pertinent drainage areas.

112

Figure 59. Minot to Bantry Schematic

Table 41. Minot to Bantry Drainage Areas

Location Total Drainage Area Contributing Drainage Area

mi2 km2 mi2 km2

Souris River above Minot, ND 10,600 27,454 3,900 10,101

Souris River near Velva, ND 11,000 28,490 4,330 11,215

Souris River near Verendrye, ND 11,300 29,267 4,400 11,396

For this analysis, the following daily flow timeseries are estimated from 2012 to 2017:

Local flow between Minot, ND and Velva, ND

Souris River near Velva, ND

Local flow between Velva, ND and Verendrye, ND


The hydrologic routing based methodology (holdout method) is used to develop local flow

hydrographs from Minot, North Dakota to Verendrye, North Dakota between 2012 and 2017. To

ensure homogeneity with local flow hydrographs developed from 1946 to 2013 as part of the

2013 Regional and Reconstructed Hydrology Study, this analysis adopts the Muskingum-Cunge

8-Point Cross Section routing parameters used in the 2013 study from Minot to Velva and Velva

to Verendrye. These are the same routing parameters adopted within the HH6 HEC-ResSim

model being used in support of the Plan of Study. A preliminary HEC-RAS unsteady hydraulic

model developed by Barr Engineering was used to develop those routing parameters. Detailed

information regarding the hydrologic routing parameters used in this analysis can be found in

Section 7.1 of the 2013 Regional and Reconstructed Hydrology Study report in Attachment A.


Local flows from Minot, North Dakota to Velva and Velva to Verendrye, are estimated using

gaged data and the hydrologic routing model applied within the HH6 ResSim model. The

reservoir network for this model is shown in Figure 60.

Bantry, ND

Bonnes Coulee

Minot, ND

Souris River

Velva, ND

Key

Ungaged

Gaged

Junction

Direct Routing

Mod Puls

Not Modeled

Local flow

Verendrye, ND

Wintering River - Karlsruhe

113

Figure 60. HEC-ResSim Routing Model Network - Minot to Verendrye

Local flow hydrographs representative of the flow contribution from the local area between

Minot and Velva and the local area between Velva and Verendrye are determined by inputting

observed streamflows at Minot and running the above model without local flow contributions

from Minot to Velva and Velva to Verendrye to compute flows at Verendrye. The resulting

hydrograph at Verendrye is subtracted from the observed record at Verendrye for 2012 to 2017.

The resulting holdout hydrograph is representative of the total local flow contributions for Minot

to Verendrye. This total local flow is then multiplied by drainage area ratios and lagged as shown

in Table 42 to compute the local flows for the two subreaches.

Table 42. Minot to Bantry Local Flow Reach Parameters

Local Flow Reach Contributing Drainage Area Drainage Area

Ratio Lag

(days) mi2 km2

Minot, ND to Velva, ND 430 1,114 0.86 1

Velva, ND to Verendrye, ND 70 181 0.14 0

After each local flow hydrograph is computed, the local flows are added to the HEC-ResSim

model, and the model is recomputed. Then, to further improve the estimate of each local flow

hydrograph, the difference between the routed and observed hydrograph at Verendrye is

minimized by iteratively distributing the difference between the routed and observed

hydrographs utilizing the same drainage area ratios and lags shown in Table 42. Figure 61 and

Figure 62 show the modeled and observed discharges at Verendrye for the years 2013 and 2014,

respectively.

114

Figure 61. Observed vs. Modeled Discharge - Verendrye, 2013

115

Figure 62. Observed vs. Modeled Discharge - Verendrye, 2014


After computing local flows, the flow hydrograph at Velva is computed by routing observed

flows at the Souris River above Minot, North Dakota to Velva with the aforementioned HEC-

ResSim routing model, this time including the estimated local flow hydrograph from Minot to

Velva. The selected simulation is “Minot_Westhope.”

6.3.7 2012 – 2017 Bantry, ND to Westhope, ND

The upstream extent of the J. Clark Salyer National Wildlife Refuge is near Bantry, North

Dakota and the refuge extends 120.7 km (75 mi) downstream to the international border at

Westhope, North Dakota. The refuge is made up of five pools created by five low-head dams

with water control structures. In total, the five pools make up 9,520 hectares (23,525 acres) of

impounded riverine marshes. More detailed information regarding the make-up of J. Clark Salyer

National Wildlife Refuge and its associated hydraulic structures can be found in Section 8 of the

2013 Regional and Reconstructed Hydrology report, Attachment 1.

There are four tributaries to the Souris River between Bantry and Westhope: Willow Creek, Cut

Bank Creek, Stone Creek, and Boundary Creek. The Deep River is a tributary to Cut Bank

Creek. While the Willow Creek near Willow City streamflow gage (USGS 5123400) spans the

116

period of record for this analysis, the streamflow gages on Cut Bank Creek, Stone Creek, and

Boundary Creek were discontinued in 2000. The Deep River gage is currently active. A

schematic of the HEC-ResSim routing model used to verify local flows estimated for this reach

is shown in Figure 63. Table 43 lists all pertinent streamflow gages from Bantry to Westhope

along with their corresponding drainage areas.

117

Figure 63. HEC-ResSim Routing Model (from the 2013 Souris River Feasibility Study)

Cut Bank Creek

Deep River

118

Table 43. Pertinent Streamflow Gages from Bantry to Westhope

Station ID Description Period of Record

Drainage Area

Gross Contributing

mi2 km2 mi2 km2

5123900 BOUNDARY CREEK NEAR LANDA 1957-2000 230 596 170 440

5123750 CUT BANK CREEK AT UPHAM 1974-2000 722 1,870 272 704

5123510 DEEP RIVER NEAR UPHAM 1957-Present 975 2,525 370 958

5122000 SOURIS RIVER NEAR BANTRY 1937-Present 12,300 31,857 4,700 12,173

05NF012/ 05124000

SOURIS RIVER NEAR WESTHOPE 1929-Present 16,900 43,771 6,600 17,094

5123500 STONE CREEK NEAR KRAMER 1986-2000 168 435 N/A N/A

5123400 WILLOW CREEK NEAR WILLOW CITY 1956-Present 1,160 3,004 730 1,891


All hydrologic routing used in the HEC-ResSim routing model from Bantry to Westhope is null

routing, except for the Souris River from Bantry to Willow Creek’s confluence with the Souris

River. For this reach, the Muskingum-Cunge 8-Point Cross Section routing parameters used in

the 2013 Regional and Reconstructed Hydrology Study and the HH6 HEC-ResSim model are

adopted. See Section 7.4 of the 2013 report (Attachment 1) for more details regarding the

development of those routing parameters.


All five of the tributaries that contribute to the Souris River between Bantry and Westhope are at

minimum partially gaged. The gross and contributing drainage areas associated with these gage

sites are displayed in

119

Table 44. As shown in

120

Table 44, there is approximately 291 square miles of unaccounted for local drainage area

between Bantry, North Dakota and Westhope, North Dakota. Due to the presence of the J. Clark

Salyer National Wildlife Refuge pools, the methodology used to compute local flows upstream

of Bantry cannot be used to compute local flows through the refuge. Instead, the total local area

flow between Bantry and Westhope is estimated utilizing a drainage area ratio applied to the

adopted flow hydrograph for the Deep River near Upham, North Dakota. The total local flow

hydrograph is then distributed throughout the river reach between Bantry and Westhope based on

drainage area ratios in accordance with Table 45.

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Table 44. Drainage Areas between Bantry, ND and Westhope, ND

Pertinent Drainage Areas between Bantry, ND and Westhope, ND

Period of Record


mi2 km2 mi2 km2

Souris River near Bantry, ND 1937-Active 12,300 31,857 4,700 12,173

Willow Creek near Willow City 1956-Active 1,160 3,004 730 1,891

Deep River near Upham 1957-Active 975 2,525 370 958

Cut Bank Creek at Upham 1974-2000 722 1,870 272 704

Stone Creek near Kramer* 1986-2000 168 435 671 1,738

Boundary Creek near Landa 1957-2000 230 496 170 440

Souris River near Westhope, ND 1939-Active 16,900 43,771 6,600 17,094

Total Intervening Drainage Area 1,900 4,921

Total Unaccounted for Intervening Drainage Area 291 754

Ungaged Local Area Drainage Area Ratio with Deep River 0.79 * The Contributing Drainage area for Stone Creek near Kramer was estimated based on the assumption that only 40% of

the drainage area contributes flow. This was consistent with the percentage of contributing drainage area within the Deep

River watershed and the overall contributing drainage area reported at Bantry and Westhope.

Table 45 - Ungaged Local Flow Distribution between Bantry, ND and Westhope, ND

Distribution of Ungaged Local Flow Hydrograph

Total Unaccounted for Drainage Area Percent of Total Intervening Area mi2 km2

Souris River near Bantry, ND 12,300 31,857

Total Unaccounted for Drainage Area 540 1,399 40%

Souris River to Dam 320/326 14,000 36,260

Total Unaccounted for Drainage Area 335 868 25%

Souris River to Dam 332 16,200 41,958


Souris River to Dam 341 16,300 42,217


Souris River to Dam 357/ Westhope, ND 16,900 43,771

Unaccounted for Gross Area Bantry, ND to Westhope, ND 1,345 mi2 3,484 km2


In order to compute local flows from Bantry to Westhope, the daily streamflow records for

Boundary Creek near Landa, Stone Creek near Kramer, and Cut Bank Creek near Upham must

first be estimated. Daily flow timeseries for each of these sites are estimated using MOVE.3,

General Relations, and the Flow Duration methodology. The record extension technique used for

each site is consistent with the methodology used in the 2013 Regional and Reconstructed

Hydrology Study, except MOVE.1 is replaced in all instances with MOVE.3. When compared to

MOVE.1 results, MOVE.3 flows are nearly identical, but are consistently one to five percent

lower in magnitude. MOVE.3 is ultimately used for this analysis to comply with the most current

guidance issued by the USGS regarding statistical daily flow estimation techniques (Reference

10).

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Boundary Creek near Landa, ND

MOVE.3 is used to estimate the daily flow timeseries at Boundary Creek near Landa, North

Dakota for the period 2012 to 2017. Boundary Creek near Landa has a period of record from

1957 to 2000. The long-term station used in this analysis is the Deep River near Upham, North

Dakota, which has a period of record from 1957 to present. Both of these sites have several gaps

in their periods of record, resulting in 36 years of concurrent record between short-term

(Boundary Creek) and long-term (Deep River) sites. Also, the gages at both of these sites are

seasonal gages, meaning there is no streamflow record during the winter months. For the purpose

of this analysis, the daily flow hydrograph at the Deep River near Upham is linearly decreased to

0 m3/s (0 ft3/s) once the gage stops recording in the late fall or winter and kept at 0 m3/s (0 ft3/s)

until the gage starts recording again in the spring.

To maintain homogeneity with the 2013 Regional and Reconstructed Hydrology Study, observed

annual spring (March through May) maximum flows are compared between the two sites. As

seen in Figure 64 there is adequate correlation between flows on Boundary Creek and flows on

Deep River (R2 = 0.76).

Figure 64. Annual Spring Maximum Flows - Boundary Creek vs. Deep River

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For some years in the concurrent period of record, the annual spring maximum flow at Boundary

Creek was 0 m3/s (0 ft3/s). To avoid errors computing MOVE.3 statistics (which are computed in

log space), all years with 0 m3/s (0 ft3/s) in normal space are assumed to be equivalent to 0 m3/s

(0 ft3/s) of flow at both sites.

After MOVE.3 statistics are computed for the concurrent period of record, the MOVE.3

equations are applied to the annual spring maximum flows at Boundary Creek near Landa.

Figure 65 shows observed spring maximums compared to modeled spring maximums at

Boundary Creek for the concurrent period of record.

Figure 65. Observed vs. Modeled Spring Maximums - Boundary Creek near Landa, ND

Since the resulting Nash-Sutcliffe coefficient of 0.773 is greater than 0.7, the same MOVE.3

statistics are used to estimate daily flows on Boundary Creek using the Deep River near Upham

daily flow record. Figure 66 and Figure 67 show estimated daily flow hydrographs compared to

the observed record for 1974 and 1999, respectively.

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Figure 66. Observed vs. Modeled Discharge, Boundary Creek near Landa, 1974

125

Figure 67. Observed vs. Modeled Discharge, Boundary Creek near Landa, 1999

Stone Creek near Kramer, ND

MOVE.3 is used to estimate the daily flow timeseries at Stone Creek near Kramer, North Dakota

for the period 2012 to 2017. Stone Creek near Kramer has a period of record from 1986 to 2000.

The long-term station used in this analysis is Boundary Creek near Landa, North Dakota, which

has a period of record from 1957 to present. Both of these sites have several gaps in their periods

of record, resulting in 10 years of concurrent record between short-term (Stone Creek) and long-

term (Boundary Creek) sites. Also, the gages at both of these sites are seasonal gages, meaning

there is no streamflow record during the winter months. For the purpose of this analysis, the

daily flow hydrograph at Boundary Creek near Landa is linearly decreased to 0 m3/s (0 ft3/s)

once the gage stops recording in the late fall or winter and kept at 0 m3/s (0 ft3/s) until the gage

starts recording again in the spring.

To maintain homogeneity with the 2013 Regional and Reconstructed Hydrology Study, observed

annual spring (March through May) maximum flows are compared between the two sites. As

seen in Figure 68, there is a high degree of linear correlation between flows on Stone Creek and

flows on Boundary Creek (R2 = 0.95).

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Figure 68. Annual Spring Maximum Flows - Stone Creek vs. Boundary Creek

After MOVE.3 statistics are computed for the concurrent period of record, the MOVE.3

equations are applied to the annual spring maximum flows at Stone Creek near Kramer.

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Figure 69 shows observed spring maximums compared to modeled spring maximums at Stone

Creek for the concurrent period of record.

128

Figure 69. Observed vs. Modeled Spring Maximums - Stone Creek near Kramer, ND

Since the resulting Nash-Sutcliffe coefficient of 0.89 is greater than 0.7, the same MOVE.3

statistics are used to estimate daily flows on Stone Creek using the adopted Boundary Creek

daily flow record. The adopted Boundary Creek daily flow record is a continuous daily

timeseries consisting of the 1945 to 2012 record estimated in the 2013 Regional and

Reconstructed Hydrology Study and the 2012 to 2017 record estimated in this analysis. Figure

70 and Figure 71 show estimated daily flow hydrographs compared to the observed record for

1987 and 1999, respectively.

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Figure 70. Observed vs. Modeled Discharge - Stone Creek, 1987

130

Figure 71. Observed vs. Modeled Discharge - Stone Creek, 1999

Cut Bank Creek at Upham, North Dakota

To maintain homogeneity with the 2013 Regional and Reconstructed Hydrology Study, two

different record extension techniques are used to estimate daily flow timeseries for Cut Bank

Creek at Upham, North Dakota, flow duration for the months April through August, and general

relations for the months September through March. This methodology was originally chosen

because there are two lakes just upstream of the Cut Bank Creek gage, North Lake and Buffalo

Lodge Lake, as shown in Figure 72.

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Figure 72. Cut Bank Creek at Upham, ND Map

Since these lakes attenuate flows observed at the gage site, Cut Bank Creek is not hydrologically

similar to other gage sites in the basin and cannot be extended using a regression based

methodology (such as MOVE.3). Furthermore, judging by the observed record at Cut Bank

Creek, it is likely that very little flow exits North and Buffalo Lodge lakes in the fall and winter

months (September through March). Therefore, during the fall and winter months, flows are

approximated based on the assumption that only the local runoff downstream of North and

Buffalo Lodge lakes contributes to flows observed at the Cut Bank Creek gage site.

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General relations methodology is used to estimate that local runoff for September through

March, 2012 to 2017, utilizing the Deep River near Upham, North Dakota gage. To compute

flows at Cut Bank Creek, the Deep River near Upham record is multiplied by a drainage area

ratio of 0.076. If no flow was recorded at Deep River, a flow of 0 m3/s (0 ft3/s) is assumed at Cut

Bank Creek. This is a valid assumption since the Deep River gage is a seasonal gage and does

not record over the winter months when flow is at or near 0 m3/s (0 ft3/s). Pertinent drainage

areas are shown in Table 46.

Table 46. Cut Bank Creek Contributing Drainage Areas (ContributingD.A)

Location Contributing Drainage Area

mi2 km2

Deep River near Upham, ND 370 958

Cut Bank Creek at Upham, ND 272 704

Cut Bank Creek at North Lake Outlet 244 632

Local Drainage from North Lake Outlet to Upham, ND 28 73

Drainage Area Ratio between Deep River and Local Drainage: 0.076

Flow duration methodology is utilized to estimate flows for April through August, 2011 to 2017.

The Deep River near Upham, North Dakota gage is used as the long-term site. Duration curves

are generated using the adopted Deep River near Upham record, which consists of the adopted

record from the 2013 Regional and Reconstructed Hydrology Study (1946-2012) and additional

observed records through 2017, as well as the duration curves utilized in the 2013 study for Cut

Bank Creek at Upham, which are generated using the extended record from 1956 to 2000. More

information regarding the methodology used to estimate the streamflow record at these sites

prior to 2012 can be found in the 2013 Regional and Reconstructed Hydrology Study report in

Attachment 1. Resulting flows are lagged one day, such that the timing of the estimated peak

matched the timing of the observed peak in 1976, the highest recorded discharge.

The adopted Cut Bank Creek daily flow record is a continuous daily timeseries consisting of the

1946 to 2011 record estimated in the 2013 Regional and Reconstructed Hydrology Study and the

2011 to 2017 record estimated in this analysis. In this case, the adopted record includes the

newly estimated record for the year 2011, because the 2013 study did not adequately account for

flows at Deep River near Upham, North Dakota in April 2011. Figure 73, Figure 74, Figure 75

and Figure 76 show estimated daily flow hydrographs compared to the observed record for 1975,

1976, 1979 and 1999, respectively. Some years are estimated better than others, as shown by the

wide range of Nash-Sutcliffe coefficients in the figures below.

133

Figure 73. Observed vs. Modeled Discharge - Cut Bank Creek, 1975

134


135


136


J. Clark Salyer National Wildlife Refuge Pools

There are five low-head dams across the mainstem Souris River within the refuge creating pools

operated for wildlife management. Each dam consists of a low earthen dike, a gated outlet

structure, and an uncontrolled spillway. Pertinent structure data related to the five major control

structures is listed in the 2013 Regional and Reconstructed Hydrology Report (Attachment 1,

Section 8).

The HEC-ResSim model shown previously in Figure 63, as well as the ResSim model developed

for the Plan of Study, simulates operation of the J. Clark Salyer pools by modeling the pools as

connected reservoirs. Evaporation is modeled using an approximation of total monthly

evaporation. Evaporation is acquired from the National Oceanic and Atmospheric

Administration’s (NOAA) National Climate Data Center (NCDC). Pan evaporation is measured

by Minot Experiment station GHCND: USC00325993 near Minot, ND. The class A pan

evaporation factor is used to adjust recorded pan evaporation numbers to gross evaporation (see

section 5.3 of Attachment 1 for more information. The same total monthly evaporation

relationship is used for each of the five refuge pools.

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Table 47. Monthly Total Evaporation J. Clark Salyer Refuge Structures

Month Total Evaporation

in mm

Jan 0 0

Feb 0 0

Mar 0 0

Apr 2.4 61

May 4.68 119

Jun 4.45 113

Jul 5.26 134

Aug 5.11 130

Sep 3.61 92

Oct 2.92 74

Nov 0 0

Dec 0 0

Each reservoir is assigned a guide curve that approximates the seasonal operation of the pool.

For this analysis, guide curves for each dam in the refuge (Dam 320, 326, 332. 341, 357) are

extended for the period 2012 to 2017 following the same pattern as the guide curves developed

for the 2013 Regional and Reconstructed Hydrology Study (Attachment 1, Section 8). The guide

curves mimic the five-year water management plan shown in

138

Table 48. For a more detailed description of the J. Clark Salyer National Wildlife Refuge

structures, modeling assumptions, and development of the drawdown schedule, see Section 8 of

the 2013 Regional and Reconstructed Hydrology Study report in Attachment 1.

139

Table 48. J. Clark Salyer National Wildlife Refuge Water Management Plan

Pool Year

1 2 3 4 5 HF

320 1417.7 (432.1)

1422.7 (433.6)

1423.7 (433.9)

1423.7 (433.9)

1425.8 (434.6)

1425.8 (434.6)

326 1417.1 (431.9)

1420.2 (432.9)

1420.7 (433.0)

1420.7 (433.0)

1421.2 (433.2)

1421.2 (433.2)

332 1417.1 (431.9)

1418.1 (432.2)

1418.1 (432.2)

1419.1 (432.5)

1415.6 (431.5)

1419.1 (432.5)

341 1415.6 (431.5)

1416.6 (431.8)

1407.2 (428.9)

1414.6 (431.1)

1415.6 (431.5)

1416.6 (431.8)

357 1413.0 (430.7)

1415.8 (431.5)

1407.2 (428.9)

1412.4 (430.5)

1413.0 (430.7)

1415.8 (431.5)

Notes

1) Entries are pool elevations

2) Pool Drawdown conditions are underlined

3) HF Option used during high flow years (Flood Recurrence Interval > 10 years)

4) Boxed Entries Reflect High Flow Conditions or Management to Control Cattail

5) Grey entries are in feet, (black entries are in meters)

Figure 77, Figure 78, Figure 79, Figure 80, and Figure 81 show the extended guide curves for

each refuge pool. These guide curves follow the operating patterns established in the 2013

analysis. The high flow (HF) option is used in 2013 and 2017 for each pool since those years

were flood years per Annex A of the 1989 International Agreement.

140

Figure 77. Pool 320, Extended Guide Curve

141


142


143


144


After extending the guide curve for each refuge pool, estimating tributary inflows, and

estimating ungaged local flow inputs, the ResSim routing model is run, and flows are computed

at Westhope, North Dakota. Figure 82, Figure 83, Figure 84, and Figure 85 show the modeled

and observed discharges at Westhope, North Dakota for the years 2011, 2014, 2015, and 2017,

respectively. With the adopted local flow inputs, the model approximates most years reasonably

well.

145

Figure 82. Observed vs. Modeled Discharge - Westhope, 2011

146


147


148


7. Data Limitations & Recommendations for Future Study

As with any analysis the methods and datasets used to execute this assessment have their

strengths and weakness. As a result of the limitations and assumptions made in generating the

regional and reconstructed hydrologic datasets (inflows to reservoirs, local flow records and

tributary flow records for 1930 to 2017) there is an embedded degree of uncertainty that varies

with flow magnitude, location and water year in the streamflow datasets produced. Uncertainty is

greatest for timeseries generated for portions of the period of record where observed streamflow

measurements are scarce. There is more uncertainty related to the approximation of low flows

then moderate or high flows. Key data limitations and potential recommendations for

improvement as part of future study efforts are highlighted in the subsequent subsections.

7.1 Hydrologic Routing

Hydrologic routing is relied upon to generate local flow timeseries. Four different hydrologic

routing techniques are applied to model the Souris River Basin: Direct (null) routing, Mod Puls,

Muskingum Cunge and Muskingum routing. Mod Puls relies on the use of storage – discharge

relationships, Muskingum Cunge routing requires channel cross section data as well as channel

149

slope, reach length and Manning’s n, Muskingum is a simple, two parameter routing method that

roughly accounts for flood wave timing and attenuation.

7.1.1 Identified Limitations

Hydrologic routing does not capture the attenuation and timing of the flood wave as accurately

as a hydraulic routing. The advantage of using hydrologic routing versus hydraulic routing is that

it minimizes run times. The routing reaches between Sherwood and Lake Darling, as well as

between Verendrye and Towner apply Muskingum two parameter routing. Muskingum routing

does not account for the variability in timing and attenuation as the quantity of flow changes.

7.1.2 Recommendation for Future Study

Ideally, a hydraulic model would be used to develop modified puls routing relationships for the

portions of the system currently modeled using Muskingum Routing. At minimum, river cross

section data should be collected so that these reaches could be modeled using physically based

Muskingum Cunge Routing.

7.2 J. Clark Salyer Refuge Structures

Routing flows through the J. Clark Salyer Refuge structures is necessary to augment tributary

input records and define local flow hydrographs. The hydrologic routing model applied in the

HEC-ResSim model incorporates the U.S Fish and Wildlife Service’s (USFWS) five-year

operating cycle (pools are alternately drawdown or raised) and elevation-storage discharge

relationships to mimic operation of the refuge pools (pools 320, 326, 332, 342, and 357).

7.2.1 Identified Limitations

Simplifying assumptions are used to model the J. Clark Salyer National Wildlife structures in

HEC-ResSim. The pool outlets are modeled using a broad crested weir equation. Without an

observed, continuous tailwater timeseries dataset HEC-ResSim is not able to account for

tailwater effects on refuge structure releases. Consequently, flows through the Refuge structures

might be overestimated.


Ideally, a HEC-RAS model would be used to better inform the tailwater limitations at each of the

J. Clark Refuge structures. To improve future modeling of the J. Clark Structures it would be

beneficial to establish pool and outflow gages at the impoundments. Modeling assumptions

related to the structures could be further refined by carrying out a detailed study of real-time

operations over an extended period. Updated physical capacity curve data and more accurate

evaporation data could be obtained and incorporated into the model.

7.3 Negative Flows

Grant Devine and Rafferty Reservoir inflows are developed using a reverse routing computation

procedure to estimate the inflow based on observed changes in pool elevation (changes in

volume) and observed outflows. Many of the local flow timeseries generated as part of this effort

150

are estimated using the holdout hydrograph computation procedure. The holdout hydrograph

calculation involves routing a hydrograph from an upstream junction to a downstream junction

which has an observed hydrograph. The difference between the observed hydrograph at the

downstream junction and the routed hydrograph represents the local flow contributions from the

intervening drainage area along the routing reach.

Reverse routing and local flow computations rely on a mass balance approach, and thus the

resulting flow record will include any errors in observed data, errors in the adopted routing

relationships and the cumulative effect of any losses or gains that are not explicitly accounted for

in the calculation. When the cumulative impact of net losses not directly accounted for or

negative error is greater than the amount of runoff which reaches the reservoir or element in the

model, this results in a negative computed flow. The negative flows are still valid and need to be

carried forward and applied, because they satisfy conservation of mass.

7.3.1 Identified Limitation

When reservoir inflows and local flow hydrographs are applied to approximate flows

representative of scenarios where the original, mainstem flow contributions have been altered

from the observed records used to produce the reservoir inflow and local flow timeseries, there

are cases where the negative flows cannot be handled by the ResSim model and are omitted. This

results in a violation of the conservation of mass within the ResSim network.

Negative inflows to reservoir elements are not an issue, because the storage volume of each

reservoir element is significantly larger than the negative inflows, and conservation of mass is

maintained when flows are routed through the reservoir even if the inflow records contain

negative values. Conservation of mass can be an issue for routing reaches which use any routing

method other than null routing. Negative flows which are routed through non-null routing

reaches are assumed to be zero during the routing operations carried out by ResSim. When

negative flows are zeroed out in a routing reach, negative volume is not accounted for in the

system, and the model ends up with a higher volume than it would have if conservation of mass

were maintained.

The amount of negative flow volume zeroed out of the reservoir network depends on the

magnitude of negative flows in the local flow records added to the system and the overall,

magnitude of flow being routed through the reservoir system. When the magnitude of the

negative local flow for a time-step is greater than the positive flow magnitude being applied from

the upstream reach for that same time step, the result is a negative flow for that time step at the

junction. When the negative flows computed for the junction are routed through a non-null

routing reach below the junction, the negatives are zeroed out and negative volume is not

accounted for in the system. The model ends up overestimating volume. The impact of this

limitation has been evaluated in depth within the HH6 ResSim report (see Section 3.3.2 of the

HH6 Report).

As part of the HH6 ResSim model development, a sensitivity analysis was performed at

Sherwood and Minot to approximate how much negative volume was unaccounted for during

four trial events. Events selected were 1976 (a high flow event), 1978 (an average magnitude

event), 2003 (a low flow event), and 2011 (a high flow event). A range of event magnitudes were

selected to show the effect that flow in the system has on the amount of volume lost. To assess

151

the magnitude of negative flows unaccounted for within the model, flow hydrographs were

compared at the upstream and downstream ends of the routing reaches. The sensitivity analysis

was performed for Sherwood and Minot for the regulated case and the unregulated case since

different model calculations and decisions depend on these different types of timeseries.

For regulated flow conditions, negative inflows do not significantly impact high, average or low

flow events. Only a small amount of negative flow is being unaccounted for, and this is unlikely

to have a significant impact on results for the regulated case. For the unregulated case, the

amount of volume lost during the high and average flow years is not significant. During the low

flow event analysed, the missing volume represents a 15% difference in volume at Sherwood.

This indicates that the apportionment calculation could be impacted during low flow events. The

apportionment may overestimate how much water would have reached Sherwood.

It is not anticipated that the negative flow values will have a significant impact on the results for

the regulated case at Sherwood or Minot or for unregulated cases when high or moderate flows

are present in the system. The cumulative, unregulated volume at Sherwood is used to trigger

flood operations, maximum downstream release rules at Sherwood and Minot, and to initiate an

extended drawdown at Lake Darling. A minimal amount of negative flow may not be accounted

for within the computation of cumulative unregulated flow at Sherwood. Because these

computations are only carried out for high flow conditions, it can be assumed that the impact of

not accounting for negative flows will have a negligible impact on modeled flood operations.

The error in model results at Sherwood or Minot is likely to be highest for the unregulated case,

under low flow conditions. This would directly affect how the model carries out the

apportionment calculation, because apportionment releases are reliant on the determination of the

unregulated record at Sherwood. The effect on the apportionment estimate is that the modeled

volumes will be higher than they should be because negative flow volume is not accounted for in

the system. For the Souris River Plan of Study, the ResSim model will be used to compare

reservoir management alternatives. Since the model is being used as a comparative tool, it is not

anticipated that the lost negative flow volume will impact how alternatives are ranked, because

the impact of zeroing out the negative flow volumes should be relatively consistent from

alternative to alternative. However, because the model may not accurately replicate reservoir

operation at very low flows, model results should be interpreted in a relative rather than absolute

sense during drought conditions. During these conditions, results should be viewed as more

qualitative than quantitative.

7.3.2 Recommendation for future study

To improve the current analysis errors in observed data, errors in the adopted routing

relationships and the cumulative effect of any losses or gains that are not explicitly accounted for

in the calculations could be minimized by improving hydrologic routing methods and further

investigating direct loses or gains to the system (evaporation, seepage loss, consumptive water

use etc.). Improvements and expansion of the gaged streamflow network could also offer

opportunities to better inform the computation of hydrologic forcings in the basin.

Another avenue that could be pursued would be more extensive precipitation-runoff modeling to

produce inputs to the ResSim model. Defining local flow contributions and filling in missing

tributary and reservoir inflow records using output from precipitation-runoff models would

152

resolve the issue of negative inflows, but would present other limitations and sources of

uncertainty. Weakness associated with relying on precipitation runoff models include limitations

on computational resources, lack of available input datasets to force the hydrologic model, lack

of reliable data to support calibration/validation, weakness associated with historic

meteorological records and uncertainty with regards to hydrologic model calibration and

performance.

7.4 Streamflow Data Availability & Quality

Between 1930 and 2017, the coverage provided by daily, streamflow recording gages varies

considerably.


There is very limited streamflow data available prior to 1946 downstream of Minot, North

Dakota. Even upstream of Minot, data collected during the 1930s is relatively scarce. Many

streamflow gages in the Souris River Basin have been discontinued or have significant portions

of missing data. In general, streamflow gages tend to more accurately capture moderate to high

flows and are less accurate at capturing quantities of low flows. Some of the gages in the Souris

River Basin only record flows ephemerally. Lack of available observed, streamflow data in the

drier 1930s period as well as general limitations on low flow measurements make the low flow

records used as part of this assessment more suspect.


Emphasis on the importance of continued data collection and expanded data collection networks

should be communicated to decision makers within the basin. Monetary resources should be

secured in the long-term to support maintaining high quality and continuous instrumental

records. Locations where additional data would benefit analyses such as this one should be

identified, and gages should be installed and maintained. Gage metadata should be catalogued,

kept up-to-date and should highlight data quality issues and data collection thresholds.

Attempting to reconstitute and evaluate flows at a daily time step during low flow periods using

the same models, techniques for record generation, and metrics as are used for the more

moderate and high flow regimes has its shortcomings. Resources were limited for the Souris

River Plan of Study, so it was necessary to adopt an approach that could be used to reasonably

evaluate a variety of data using a consistent and comparative methodology. Future study could

be dedicated to identifying alternate means of analysis specifically targeted at evaluating

operations under low flow/drought conditions. This would likely involve tapping into additional

data sources like ground water records, temperature records, and datasets representative of soil

moisture and evapotranspiration. Models specifically designed to simulate drought conditions

could be researched and applied.

153

7.5 Characterization of Direct System Loses and Gains

Limited data is readily available characterizing direct loses from reservoirs and riverine reaches.

Although daily precipitation records are readily available throughout the basin, daily evaporation

records are scarce. Being able to accurately characterize direct loses from the system becomes

particularly important when attempting to analyse system response during dry conditions.


Daily evaporation records (or alternative timeseries which could be used to generate a daily

evaporation record) were not found to be available for the study area for the period of analysis

1930 to 2017. Monthly gross evaporation records generated using the Meyer’s Equation are

adopted in support of this analysis. Gross evaporation records are not available at a lot of

locations within and nearby the study area. Consequently, there is a lot of uncertainty associated

with how evaporative loses vary spatially throughout the basin. The dataset used does not

account for sub-monthly variation in evaporation throughout the period of record.

Simplifying assumptions are applied to account for consumptive water uses from Boundary

Reservoir, pumped releases from Rafferty to Boundary Reservoir and from riverine reaches

downstream of Lake Darling in support of the Eaton Irrigation District. Additional consumptive

water usage directly from Rafferty, Grant Devine, Lake Darling and riverine reaches are

assumed to be negligible.

The effects of seepage on reservoir pools and riverine reaches is unknown. It is apparent that a

significant accounted for loss occurs form Rafferty Reservoir. Based on the magnitude and

timing of the identified loss it is assumed that this can be attributed to a seepage loss.

Consequently, seepage losses are coarsely approximated and accounted for from Rafferty

Reservoir. Seepage loses are assumed to be negligible at the other reservoirs and along riverine

reaches.


To better understand system response during dry conditions, further investigation could be

carried out to identify finer scale evaporation records. If daily evaporation datasets are available

for a portion of the period of record and/or at a finer spatial resolution, an evaluation could be

carried out to assess the impact of using the coarser scale evaporation datasets versus the finer

scale datasets. If necessary, a study could be conducted to measure evaporation at each reservoir

directly.

More research could be conducted to better understand direct loses from the reservoirs and the

riverine reaches. This could include an in-depth study of seepage in the basin as well as a long-

term study of consumptive water use in the basin.

8. Application

The objective of performing a regional assessment of the hydrology of the Souris River Basin is

to generate a frame of reference that can be used to review the operation of water management

structures in the Souris River Basin. This assessment provides for a best practical understanding

154

of how the basin responds to hydrologic forcings at key basin locations. As part of this analysis,

flows are approximated at the head of important reservoirs in the Souris River Basin. Observed

daily flow data is inventoried and compiled from all streamflow gages in the basin. Daily

streamflow records are estimated, filled in and extended in order to produce consistent timeseries

at all critical locations in the Souris River Basin.

The datasets generated as part of HH1 have several applications for the Plan of Study. Data

produced as part of the 2019 and 2013 Regional and Reconstructed Hydrology Studies will be

used as boundary conditions to hydrologic and hydraulic models like HEC-ResSim, HEC-RAS

and MESH. The datasets compiled as part of the 2013 study (Attachment 1) have already been

used to validate the USGS’s stochastic hydrology model and the HH6 HEC-ResSim model. The

2019 Regional and Reconstructed Hydrology will be used as a calibration/validation dataset for

MESH.

Knowledge of key hydrologic forcings in the basin can help inform the selection of water

management alternatives taken under consideration as part of the Plan of Study. The 2019

Regional and Reconstructed Hydrology will serve to provide reservoir inflows, tributary

contributions and local flow inputs that will be used as model inputs for modeling historic events

in HEC-ResSim and HEC-RAS. Reservoir inflow, tributary contributions and local flow inputs

for HEC-ResSim, and HEC-RAS will support the establishment of baseline conditions in the

Souris River Basin and will aid in the assessment of model results for proposed management

alternatives.

155

9. References

1. Canada and U.S.A (1989). “Agreement between the Government of Canada and the

United States for Water Supply and Flood Control in the Souris River Basin.”

2. Department of Defense, U.S. Army Corps of Engineers, Hydrologic Engineering Center

(2016). “HEC-DSSVue Data Storage System Visual Utility Engine, Version 2.6,” Davis, CA.


(2008). “HEC-RAS, River Analysis System,” Davis, CA


(2018). “HEC-ResSim, Reservoir System Simulation, Version 3.3,” Davis, CA.

5. Department of Defense, U.S. Army Corps of Engineers, St. Paul District (2012). “Lake

Darling Water Control Manual: Lake Darling Dam and Reservoir Souris River Basin Flood

Control,” St. Paul, MN.

6. Department of the Interior, United States Geological Survey, Advisory Committee on

Water Information (2018). “Bulletin #17C Guidelines for Determining Flood Flow

Frequency,” Reston, VA.

7. Department of Interior, United States Geological Survey, Water Information System

(Accessed 2013). “USGS Surface-Water Data for the USA,”

https://waterdata.usgs.gov/nwis/sw?.

8. Emerson, Vecchia, and Dahl, United States Geological Survey (2005). “Evaluation of

Drainage-Area Ratio Method Used to Estimate Streamflow for the Red River of the North

Basin, North Dakota and Minnesota Scientific Investigations Report 2005–5017.”

9. Government of Canada, Environment and Natural Resources (Accessed 2013). “Water

Level and Flow,” https://wateroffice.ec.gc.ca/index_e.html

10. Hirsch, R. (1982). “A Comparison of Four Streamflow Record Extension Techniques,”

Water Resources Research.

11. Hughes, D.A. and V. Smakhtin (1996). “Daily flow time series patching or extension: a

spatial interpolation approach based on flow duration curves,” Hydrological Sciences,

41:6.

12. International Joint Commission (2020). “IJC Canada-U.S. Transboundary Hydrographic

Data Harmonization,” https://ijc.org/en/what/iwi/data

13. ISRB, 2018a. Procedures for the Apportionment of Flows on the Souris River. Version

1.00, June 2018.

14. ISRB, 2018b. Draft Work Plan for the Souris River Basin. Submitted to the International

Joint Commission, October 2018.

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15. Martin, F.R.J, Agriculture and Agri-Food Canada Prairie Farm Rehabilitation

Administration Technical Service (2002). “Gross Evaporation for the 30-year Period

1971-200 in the Canadian Prairies, Hydrology Report #143,” Regina, Saskatchewan.

16. NOAA, (1982). “NOAA Technical Report NWS 34, Mean Monthly, Seasonal, and Annual

Pan Evaporation for the United States,” Washington, DC.

17. Prairie Farm Rehabilitation Administration (1988). “Determination of Gross Evaporation

for Small to Moderate-Sized Water Bodies in the Canadian Prairies Using the Meyer

Formula, Hydrology Report #113,” Hydrology Division, Agriculture Canada.

18. Prairie Farm Rehabilitation Administration, (1995). “Determination of Coefficients for

Use in the Meyer Formula, Hydrology Report #139,” Hydrology Division, Agriculture and

Agri-Food Canada.

19. PRISM Climate Group, Oregon State University, (2004). http://prism.oregonstate.edu,

(accessed 7/3/2019).

20. WSA. 2018. Personal conversation. Saskatchewan Water Security employee.

21. WSA, 2019. Email Correspondence about water use at Reservoirs with WSA employee.

hh1: 2019 regional & reconstructed hydrology

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