Upper Missouri River Basin Water Year 2017 Summary of Actual Operations U.S. Department of Interior Bureau of Reclamation Great Plains Region TABLE OF CONTENTS SUMMARIES OF OPERATION FOR WATER YEAR 2017 FOR RESERVOIRS IN MONTANA, WYOMING AND THE DAKOTAS TABLE OF CONTENTS ................................................................................................................. i INTRODUCTION ......................................................................................................................... iv MONTANA AREA OFFICE WY 2017 SUMMARY ................................................................................................................... 1 October through December ......................................................................................................... 1 January through March ............................................................................................................... 8 April through June .................................................................................................................... 10 July through September ............................................................................................................ 13 FLOOD BENEFITS...................................................................................................................... 16 UNIT OPERATIONAL SUMMARIES FOR WY 2017 .............................................................. 19 Clark Canyon Reservoir ............................................................................................................ 19 Important Events – WY 2017 ............................................................................................... 22 Canyon Ferry Lake and Powerplant ......................................................................................... 25 Important Events -WY 2017 ................................................................................................. 28 Helena Valley Reservoir ........................................................................................................... 33 Sun River Project ...................................................................................................................... 35 Important Events – WY 2017 ............................................................................................... 39 Lake Elwell (Tiber Dam) .......................................................................................................... 47 Important Events – WY 2017 ............................................................................................... 49 Milk River Project..................................................................................................................... 54 Important Events – WY 2017 ............................................................................................... 60 Bighorn Lake and Yellowtail Powerplant ................................................................................. 68 Important Events - WY 2017 ................................................................................................ 72 WYOMING AREA OFFICE WIND RIVER AND SHOSHONE RIVER BASIN CLIMATE SUMMARIES ......................... 79 Fall: October through November ............................................................................................. 79 Winter: December through February ....................................................................................... 79 Spring/Summer: March through September ............................................................................ 81 Reservoir Summary: Riverton Unit ......................................................................................... 84 i Bull Lake Reservoir .................................................................................................................. 84 Pilot Butte Reservoir ................................................................................................................. 86 Boysen Reservoir and Powerplant ............................................................................................ 92 2017 Summary ...................................................................................................................... 92 Important Events – WY 2017 ............................................................................................... 96 Anchor Reservoir ...................................................................................................................... 99 Shoshone Project and Buffalo Bill Unit.................................................................................. 102 Important Events - 2017...................................................................................................... 106 SUMMARY OF RESERVOIR OPERATIONS FOR BENEFIT OF FISH AND WILDLIFE, ENVIRONMENT, AND RECREATION .................................................................................. 109 Bull Lake Reservoir ................................................................................................................ 109 Boysen Reservoir .................................................................................................................... 109 Buffalo Bill Reservoir ............................................................................................................. 109 DAKOTAS AREA OFFICE WEATHER SUMMARY FOR NORTH AND SOUTH DAKOTA .......................................... 111 FLOOD BENEFITS.................................................................................................................... 113 Reservoirs in North and South Dakota and Northeastern Wyoming ...................................... 113 UNIT OPERATIONAL SUMMARIES FOR WY 2017 ............................................................ 115 Dickinson Reservoir................................................................................................................ 115 Background ......................................................................................................................... 115 WY 2017 Operations Summary .......................................................................................... 115 Monthly Statistics for WY 2017 ......................................................................................... 116 Heart Butte Reservoir ............................................................................................................. 118 Background ......................................................................................................................... 118 WY 2017 Operations Summary .......................................................................................... 118 Monthly Statistics for WY 2017 ......................................................................................... 118 Jamestown Reservoir .............................................................................................................. 121 Background ......................................................................................................................... 121 WY 2017 Operations Summary .......................................................................................... 121 Monthly Statistics for WY 2017 ......................................................................................... 121 ii Deerfield Reservoir ................................................................................................................. 124 Background ......................................................................................................................... 124 WY 2017 Operations Summary .......................................................................................... 124 Monthly Statistics for WY 2017 ......................................................................................... 125 Pactola Reservoir .................................................................................................................... 127 Background ......................................................................................................................... 127 WY 2017 Operations Summary .......................................................................................... 127 Monthly Statistics for WY 2017 ......................................................................................... 128 Angostura Reservoir ............................................................................................................... 130 Background ......................................................................................................................... 130 WY 2017 Operations Summary .......................................................................................... 128 Monthly Statistics for WY 2017 ......................................................................................... 131 Keyhole Reservoir .................................................................................................................. 133 Background ......................................................................................................................... 133 WY 2017 Operations Summary .......................................................................................... 133 Monthly Statistics for WY 2017 ......................................................................................... 134 Shadehill Reservoir ................................................................................................................