WIND/BIGHORN RIVER BASIN PLAN FINAL REPORT PREPARED FOR THE: Wyoming Water Development Commission BY: BRS, Inc. IN ASSOCIATION WITH: MWH, Lidstone and Associates, TriHydro Corporation, Donnell and Allred Inc, Water Rights Services LLC October 2003 Table of Contents Chapter 1 Institutional Constraints 1.1 Wyoming Water Law .....................................................1 1.2 Compacts and Decrees ....................................................1 1.2.1 Introduction ............................................................1 1.2.2 Yellowstone Compact .....................................................1 1.2.3 Big Horn General Adjudication .............................................2 1.3 Institutional Considerations ................................................2 1.3.1 Introduction ............................................................2 1.3.2 Land Ownership .........................................................3 1.3.3 Wyoming Water Development ..............................................4 1.3.4 Impact of Environmental and Cultural Concern on Regulation and Legislation .......5 1.3.5 Environmental Legislation .................................................5 1.3.6 Water Development Projects and Proposals ...................................7 Chapter 2 Water Use 2.1 Wind/Bighorn Lands Mapping and Water Rights Data ...........................1 2.1.1 Introduction ............................................................1 2.1.2 Identification and Delineation of Irrigated Lands ...............................1 2.1.3 Attribution of Water Rights to Delineated Irrigated Lands ........................3 2.1.4 Creation of a Digital Irrigated Lands Map ....................................3 2.1.5 Verification of Delineated Irrigated Lands ....................................4 2.1.6 Explanation of the Irrigated Geographic Information System (GIS) ................4 2.1.7 Water Right Type of Supply Related Terminology ...............................4 2.2 Agricultural Water Use and Diversion Requirements ............................6 2.2. 1 Introduction ..........................................................6 2.2.2 Historical Diversions .....................................................6 2.2.3 Estimated Historical Diversions ............................................7 2.2.4 Full Supply Diversion Requirements .........................................8 2.2.5 Irrigated Lands .........................................................8 2.2.6 Theoretical Crop Irrigation Requirement ....................................10 2.2.7 Cropping Patterns ......................................................13 2.2.8 Full Supply Crop Irrigation Requirement ....................................15 2.2.9 Calculation of Full Supply Diversion Requirements ............................15 2.2.10 Overall Efficiencies .....................................................15 2.2.11 Full Supply Diversion Requirements ........................................16 2.2.12 Summary and Conclusions ................................................17 2.3 Municipal Water Use Profile ..............................................18 2.3.1 Introduction ...........................................................18 2.3.2 Ground Water Use ......................................................20 2.3.3 Surface Water Use ......................................................21 2.3.4 Conclusions ...........................................................22 2.4 Domestic Water Use Profile ..............................................22 2.4.1 Introduction ...........................................................22 2.4.2 Non-Municipal Public Water System Usage ..................................23 2.4.3 Rural Domestic Water Usage .............................................23 2.4.4 Conclusions ...........................................................24 2.5 Industrial and Mining Water Use ...........................................27 2.5.1 Introduction ...........................................................27 2.5.2 Industry in the WBHB ...................................................27 2.5.3 Manufacturing .........................................................27 2.5.4 Power Production ......................................................28 2.5.5 Mining: Oil and Gas, Coal, Uranium, Bentonite, and Gypsum ...................29 2.5.6 Summary of Consumptive Industrial Use ....................................29 2.6 Environmental and Recreational Water Uses .................................30 2.6.1 Introduction ...........................................................30 2.6.2 Institutional Considerations ..............................................30 2.6.3 Land Ownership ........................................................31 2.6.4 Threatened, Endangered, and Candidate Taxa ................................31 2.6.5 Wild and Scenic Rivers ..................................................31 2.6.6 Glaciers ..............................................................32 2.6.7 Yellowstone National Park ...............................................32 2.6.8 Wind River Indian Reservation ............................................33 2.6.9 Reservoir-Allocated Conservation Pools and Recreation Permits .................33 2.6.10 Instream and Maintenance Flows and Bypasses ...............................34 2.6.11 Wetlands and Riparian Areas .............................................34 2.6.12 Waterbodies with Water Quality Impairments ................................36 2.6.13 Summary of Consumptive Uses ............................................37 2.6.14 Recreation Demands ....................................................37 2.6.15 State Parks ............................................................38 2.6.16 Fishing ...............................................................38 2.6.17 Waterfowl .............................................................40 2.6.18 Adequacy of Present Recreational Resources .................................41 2.7 Water Use From Storage .................................................41 2.7.1 Major Reservoir Information ..............................................41 2.7.2 Reservoir Descriptions ..................................................41 2.7.3 Evaporation ...........................................................42 2.8 Wind River Range Glaciers ...............................................46 2.8.1 Introduction ...........................................................46 2.8.2 Glacial Recession and Paleoclimatic Research ...............................46 2.8.3 Potential Watershed Impacts of Glaciers ....................................47 2.8.4 Summary .............................................................49 2.9 Water Conservation .....................................................49 2.9.1 Overview .............................................................49 2.9.2 Agriculture ............................................................50 2.9.3 Public Water Systems ....................................................51 2.9.4 Environmental and Recreation Considerations ................................52 2.9.5 Summary .............................................................53 Chapter 3 Surface and Groundwater Availability 3.1 Surface Water Hydrology .................................................1 3.1.1 Introduction ............................................................1 3.1.2 Historical Streamflow Records .............................................3 3.1.3 Study Period Selection ....................................................4 3.1.4 Data Filling and Extension ................................................6 3.1.5 Ungaged Headwaters Site Data Estimation ...................................7 3.1.6 Hydrologic Year Classification .............................................8 3.2 Spreadsheet Model Development and Calibration .............................10 3.2.1 Introduction ...........................................................10 3.2.2 Model Development .....................................................12 3.2.3 Model Schematics ......................................................13 3.2.4 Differences from Previous Basin Planning Models .............................23 3.3 Available Surface Water Determination .....................................24 3.3.1 Introduction ...........................................................24 3.3.2 Diversion Shortages .....................................................24 3.3.3 Streamflow ............................................................27 3.3.4 Available Flow .........................................................27 3.4 Available Ground Water Determination .....................................33 3.4.1 Introduction ...........................................................33 3.4.2 Geological Setting ......................................................34 3.4.3 Hydrostratigraphy ......................................................38 3.4.4 Ground Water Quality ...................................................41 3.4.5 Ground Water Development ..............................................42 Chapter 4 Future Water Use Projections 4.1 Socioeconomic Factors and Water Demand ...................................1 4.1.1 Methodological Considerations .............................................1 4.1.2 Demographic Overview ...................................................2 4.1.2.1 Historical Demography ...................................................4 4.1.2.2 Population Forecasts .....................................................5