RECLAMATION Managing Water in the West
Yellowtail Dam & Bighorn Lake Long Term Issues Group
Boysen Buffalo Bill Bull Lake YELLOWTAIL DAM, BIGHORN LAKE and AFTERBAY
Yellowtail Afterbay Dam
Substation
Visitor Center
Yellowtail Dam YELLOWTAIL DAM, BIGHORN LAKE AND AFTERBAY
Yellowtail Unit
• Authorization: Flood Control Act of Dec. 22, 1944 (ch.665 Stat. 887)
Senate Document 191—USACE/Reclamation plan for Missouri River Basin Development
• Project Purposes – Flood Control – Hydropower – Irrigation – Recreation – Fish & Wildlife – Sediment storage
Yellowtail Unit Project Purposes- Flood Control (Exclusive flood storage = 259K af), Coordinated with U.S. Army Corps of Engineers
Bighorn Canyon National Recreation Area
Authorization: Public Law 89-664, October 15, 1966
Purpose
“In order to provide for public outdoor recreation use and enjoyment of the proposed Yellowtail Reservoir and lands adjacent thereto in the States of Wyoming and Montana by the people of the United States….” BIGHORN RESERVOIR ALLOCATIONS Dam Crest Maximum Water Surface or Top of Surcharge Elev. 3660.00 (1,381,189 Acre-Feet) Elev. 3660.0 SURCHARGE - 52,829 Acre-Feet Top of Exclusive Flood Elev. 3657.00 (1,328,360 AF) EXCLUSIVE FLOOD CONTROL - 258,331 Acre-Feet Top of Joint Use Elev. 3640.00 (1,070,029 Acre-Feet) JOINT USE - 240,342 Acre-Feet
Top of Active Conservation Elev. 3614.00 (829,687 Acre-Feet) Spillway crest Elev. 3593.00 ACTIVE CONSERVATION - 336,103 Acre-Feet
FISH WILDLIFE RECREATION AGRICULTURE POWER MUNICIPAL INDUSTRIAL
Top of Inactive Elev. 3547.00 (493,584 Acre-Feet)
Powerplant Penstock Elev. 3450.00 INACTIVE CONSERVATION - 477,576 Acre-Feet Irrigation Outlet Elev. 3400.00
River Outlet Elev. 3300.0 Top of Dead Elev. 3296.50 (16,008 Acre-Feet)
DEAD - 16,008 Acre-Feet
Streambed Elev. 3166.0
Record Drought Water Years
• Average Bighorn Lake Inflow 1967-2006 2,373 kaf
• DPR avg. 1934-1940 Drought: 1,558 kaf
• Average Inflow Drought 2000-2006 1,384 kaf
• Lowest annual inflow of record 2002 1,030 kaf Bighorn Lake Annual Inflow Trend
4000000 3500000 3000000 2500000 2000000 1500000 1000000 Inflow acre-feet Inflow 500000 0
1967 1969 1971 1973 1975 1977 1979 1981 1983 1985 1987 1989 1991 1993 1995 1997 1999 Lake Level Versus Current Safe Launch Levels
Bighorn Lake Elevation May 20 - September 5 1997-2006
3650
Recreation periods in red 3640
3630
3620 Horseshoe Bend Safe Boat Launch
3610
Elevation (ft) Elevation 3600 Non-recreation periods in blue
3590
Ok-A-Beh & Barry’s Landing Safe Boat Launch 3580
3570 10/01/1997 02/01/1998 06/01/1998 10/01/1998 02/01/1999 06/01/1999 10/01/1999 02/01/2000 06/01/2000 10/01/2000 02/01/2001 06/01/2001 10/01/2001 02/01/2002 06/01/2002 10/01/2002 02/01/2003 06/01/2003 10/01/2003 02/01/2004 06/01/2004 10/01/2004 02/01/2005 06/01/2005 10/01/2005 02/01/2006 06/01/2006 10/01/2006 Date HORSESHOE BEND RAMP
July 27, 2001 July 17, 2002 Lake Elevation 3614.43 Lake Elevation 3588.36 Horseshoe Bend Area AUGUST 31, 2001 3603.00 LAKE ELEVATION
View Downstream of Bighorn River at Bighorn Access August 20, 2002 1536 CFS River Flow
MFWP estimates fish populations have declined from 7500 fish per mile to as low as 2200 fish per mile as minimum flows have been reduced from 2500 to 1500 cfs. View of Bighorn River at Bighorn Access August 20, 2002 1536 CFS River Flow
MFWP estimates fish populations have declined from 7500 fish per mile to as low as 2200 fish per mile as minimum flows have been reduced from 2500 to 1500 cfs. RECLAMATION Managing Water in the West
Yellowtail Dam & Bighorn Lake
Lovell, Wyoming
February 17, 2007 RECLAMATION Managing Water in the West
Yellowtail Dam & Bighorn Lake Long Term Issues Group
Bighorn River System Long-Term Issues Group
Montana: Fish Wildlife & Parks, Department of Natural Resources and Conservation
Wyoming: Fish and Game, State Engineer
Crow & Northern Cheyenne Tribes
Bighorn County Wyoming
Bighorn County Montana
Congressional Representatives
Passionate Public: Friends of Bighorn Lake, Friends of Bighorn River
Bighorn River System Long-Term Issues Group
Montana: Fish Wildlife & Parks, Department of Natural Resources and Conservation
Wyoming: Fish and Game, State Engineer
Crow & Northern Cheyenne Tribes
Bighorn County Wyoming
Bighorn County Montana
Congressional Representatives
Passionate Public: Friends of Bighorn Lake, Friends of Bighorn River
Bighorn River System Long-Term Issues Group
Montana: Fish Wildlife & Parks, Department of Natural Resources and Conservation
Wyoming: Fish and Game, State Engineer
Crow & Northern Cheyenne Tribes
Bighorn County Wyoming
Bighorn County Montana
Congressional Representatives
Passionate Public: Friends of Bighorn Lake, Friends of Bighorn River
National Park Service
3645
3640
3635
3630
3625
3620
3615
3610
3605
3600
3595 Reservoir Elevations (feet)
3590
3585
3580
3575 October November December January February Mar c h April May June July August September NPS Recreation Minimal NPS Recreation Op
BIGHORN FLOW RECOMMENDATIONS (MT FW&P) Optimal Flow - 3,500 cfs
Target Minimum Flow – 2,500 cfs
Preferred Min. Fisheries Flow – 2,000 cfs
Absolute Min. Fisheries Flow - 1,500 cfs
Rule Curves (Forecast & Reservoir Levels) Reservoir Level Targets
Date Revised Criteria Old Criteria ______Target Elevation Targets
Oct 31 3638-3640 3630-3635 (Revised Fall/Winter Inflow Formulas, On Web-Site) Mar 31 3616.7-3620.6 3605-3614
Apr-July Rule Curve
July 31 3640 3640 Rule Curve Example
Bighorn Lake Rule Curves
3640.0
3630.0
3620.0
Lake Elev. feet 3610.0
3600.0 4/7 5/5 6/2 6/9 7/7 3/31 4/14 4/21 4/28 5/12 5/19 5/26 6/16 6/23 6/30 7/14 7/21 7/28
Min Fill 28% Medium UQ UD Max Yellowtail Dam Power Generation Modified Criteria vs. Historic 1988-2008 100.0 90.0 80.0 70.0 60.0 50.0 Generation GWH 40.0 Nov Dec Jan Feb Mar Apr May Jun Jul Aug Sep Oct
Modified Criteria Historic Bighorn Lake Elev. Modified Criteria vs. Historic 1988-2008 Averages 3640 3635 3630 3625 3620 3615 3610 Lake Level feet 3605 3600 Oct Nov Dec Jan Feb Mar Apr May Jun Jul Aug Sep Oct
Modified Criteria Historic River Release Targets Existing SOP Criteria • Optimum Instream Flow 2,500 cfs • Standard Instream Flow 2,000 cfs • Minimum Instream Flow 1,500 cfs • Absolute Minimum 1,000 cfs
Revised Criteria • Prefered Instream Flow 3,500 cfs • Optimum Instream Flow 2,500 cfs • Standard Instream Flow 2,000 cfs • Minimum Instream Flow 1,500 cfs • Absolute Minimum 1,000 cfs
(Prefered fishery flow provided by Montana FW&P during issued group meetings.) Bighorn River Flows Revised Criteria vs. Historic
Bighorn River Fishery Flows 1988-2008 % of of Time above Fishery Flow Targets
100 80 60 40 20 Percent of Time 0 1300 1500 2000 2500 3500
Historic Modified Criteria Expected Benefits of Revised Operating Criteria Values Compared to Historic Operation
Lake Levels
January-April 7-8 feet higher
May-June 3 feet higher
July-December 4-5 feet higher
Expected Benefits of Revised Operating Criteria Values Compared to Historic Operation
River Flows Improvement in Percent of Time Provided
1500 cfs +8% (met 100% of time for study period) 2000 cfs +5% 2500 cfs +5% 3500 cfs -3%
Expected Benefits of Revised Operating Criteria Values Compared to Historic Operation
Power Generation Increased Generation GWHs Percent Increase
Annual +17.9 2% Dec-Feb - 2.2 -1% July-Aug - 1.8
Expected Benefits of Revised Operating Criteria Values Compared to Historic Operation
Flood Control
June Slight decrease in peak release rate
Decrease in peak reservoir level for most high runoff years
Statement of problem • Progressive side channel abandonment • Loss of habitat in side channels – Changes from 1939 to 1974 (from Koch et al 1977): • Vegetated Islands 23.1% • Island Gravel Bars 77.2% • Lateral Gravel Bars 34.0% • Water Area 7.8% – Side channel loss appears to be continuing today (based on field observations) – Side channel loss attributed to the construction of Yellowtail Dam
Bighorn River near St. Xavier, MT (#06287000)
Klines Channel Bighorn Alliance side channel work salt cedar and Russian olive removal
Water dam at head of Side Channel
Invasive Russian Olive Salt Cedar holding sediment Slated for Removal What did it look like in Feb 2012?
3,130 CFS
Big Horn Lake Sediment Management Study
Dan Pridal Omaha District Corps of Engineers Range Line 15 - Station 246853 with 40 Year Future Base Condition 3640 Average Bed for Section 3630
3620 Average Bed Change
3610
3600
3590 Elevation Feet - Original 1982 2000 2007 Base 40 Year 3580
3570 Historical model simulation period from Oct 1965 through July 2007. Observed survey data from Bureau of Reclamation rangeline surveys. 3560
3550 0 200 400 600 800 1,000 1,200 1,400 1,600 1,800 2,000 Distance - Feet Construct spaced berms to increase travel time and sediment retention within basin. Size and extent to be determined in next design phase. Sediment trap efficiency decreases for higher flow as travel time reduces.
Second option to restrict Causeway opening and use as dam. May be WY DOT issues with unequal water elevation for embankment.