Report Created: 9/15/2021 11:29:26 AM Basinwide Summary: September 1, 2021 Reservoir Storage Summary for the end of August 2021 (averages based on 1981-2010 reference period) Current Last Year Average Capacity Current % Last Year % Average % Current % Last Year % ARIZONA (KAF) (KAF) (KAF) (KAF) Capacity Capacity Capacity Average Average Lyman Reservoir 5.5 9.6 10.1 30.0 18% 32% 34% 55% 95% Salt River Reservoir System 1179.2 1188.0 2025.8 58% 59% 99% San Carlos Reservoir 27.4 58.1 261.4 875.0 3% 7% 30% 10% 22% Verde River Reservoir System 167.0 147.8 287.4 58% 51% 113% Basin-wide Total 32.9 67.7 271.5 905.0 4% 7% 30% 12% 25% # of reservoirs 2 2 2 2 2 2 2 2 2 Current Last Year Average Capacity Current % Last Year % Average % Current % Last Year % COLORADO (KAF) (KAF) (KAF) (KAF) Capacity Capacity Capacity Average Average Adobe Creek Reservoir 11.9 11.2 27.2 62.0 19% 18% 44% 44% 41% Antero Reservoir 20.1 19.6 15.5 19.9 101% 98% 78% 130% 126% Barr Lake 10.7 4.5 12.2 30.1 36% 15% 41% 88% 37% Beaver Reservoir 3.4 3.6 3.7 4.5 75% 81% 82% 91% 98% Black Hollow Reservoir 2.9 3.5 2.8 6.5 45% 54% 43% 104% 125% Blue Mesa Reservoir 310.4 495.3 670.8 830.0 37% 60% 81% 46% 74% Boyd Lake 35.7 32.4 26.0 48.4 74% 67% 54% 137% 125% Cache La Poudre 3.7 2.6 3.3 10.1 37% 26% 33% 112% 79% Carter Lake 92.2 91.5 60.7 108.9 85% 84% 56% 152% 151% Chambers Lake 4.5 6.4 2.7 8.8 51% 73% 31% 167% 237% Cheesman Lake 77.8 65.4 71.6 79.0 98% 83% 91% 109% 91% Clear Creek Reservoir 5.9 4.6 6.5 11.4 52% 41% 57% 91% 71% Cobb Lake 19.1 16.1 11.2 22.3 86% 72% 50% 171% 144% Continental Reservoir 8.0 6.6 3.2 27.0 30% 24% 12% 250% 206% Crawford Reservoir 1.7 2.6 6.5 14.0 12% 19% 46% 26% 40% Crystal Reservoir 8.9 8.4 8.0 17.5 51% 48% 46% 111% 105% Cucharas Reservoir 5.1 40.0 13% Dillon Reservoir 235.6 235.7 238.3 249.1 95% 95% 96% 99% 99% Elevenmile Canyon Reservoir 100.2 94.8 96.9 98.0 102% 97% 99% 103% 98% Elkhead Reservoir 20.2 22.8 25.6 79% 89% 89% Empire Reservoir 10.2 6.0 9.7 36.5 28% 17% 27% 105% 62% Fossil Creek Reservoir 7.0 4.4 3.5 11.1 63% 39% 32% 200% 125% Fruitgrowers Reservoir 0.5 0.2 1.2 3.6 15% 5% 34% 44% 15% Fruitland Reservoir 0.4 0.3 1.1 9.2 5% 3% 12% 40% 27% Great Plains Reservoir 0.0 36.9 150.0 0% 25% 0% Green Mountain Reservoir 80.1 111.8 128.6 146.8 55% 76% 88% 62% 87% Gross Reservoir 25.3 21.2 23.4 29.8 85% 71% 79% 108% 91% Groundhog Reservoir 4.1 10.9 14.2 26.3 16% 41% 54% 29% 77% Halligan Reservoir 4.5 1.9 3.6 6.4 70% 30% 56% 125% 53% Holbrook Lake 0.4 0.1 2.3 7.0 5% 1% 33% 15% 5% Homestake Reservoir 31.2 42.4 34.1 42.6 73% 100% 80% 92% 124% Horse Creek Reservoir 0.1 5.8 27.0 0% 21% 2% Horsecreek Reservoir 3.5 -0.8 4.7 14.7 24% -5% 32% 74% -16% Horsetooth Reservoir 117.7 82.7 82.1 149.7 79% 55% 55% 143% 101% Jackson Gulch Reservoir 3.8 2.9 5.6 10.0 38% 29% 56% 68% 52% Jackson Lake Reservoir 15.0 4.7 14.2 26.1 57% 18% 54% 106% 33% John Martin Reservoir 19.9 40.5 109.9 616.0 3% 7% 18% 18% 37% Julesburg Reservoir 9.9 4.1 7.8 20.5 48% 20% 38% 127% 53% Lake Granby 354.6 412.2 382.9 465.6 76% 89% 82% 93% 108% Lake Henry 6.3 3.5 4.9 9.4 67% 37% 52% 128% 71% Lake Loveland Reservoir 7.0 3.5 6.7 10.3 68% 34% 65% 104% 53% Lemon Reservoir 12.3 10.9 22.6 40.0 31% 27% 57% 54% 48% Lone Tree Reservoir 4.0 -0.3 3.5 8.7 46% -4% 40% 114% -9% Mariano Reservoir 1.4 0.8 1.2 5.4 26% 16% 22% 116% 70% Marshall Reservoir 5.8 5.4 6.3 10.0 58% 54% 63% 92% 86% Marston Reservoir 10.9 7.0 7.3 13.0 84% 53% 56% 149% 95% Mcphee Reservoir 164.2 198.6 292.1 381.0 43% 52% 77% 56% 68% Meredith Reservoir 12.9 12.3 19.1 42.0 31% 29% 45% 67% 64% Milton Reservoir 11.0 6.9 9.4 23.5 47% 29% 40% 117% 73% Morrow Point Reservoir 109.8 110.1 112.7 121.0 91% 91% 93% 97% 98% Mountain Home Reservoir 4.1 1.0 3.3 18.0 23% 5% 18% 124% 29% Narraguinnep Reservoir 1.2 5.0 12.3 19.0 6% 26% 65% 10% 40% Paonia Reservoir 1.0 0.3 7.3 15.4 6% 2% 47% 13% 4% Platoro Reservoir 15.1 14.6 27.5 60.0 25% 24% 46% 55% 53% Point Of Rocks Reservoir 17.3 11.1 16.4 70.6 25% 16% 23% 105% 68% Prewitt Reservoir 12.1 7.3 12.1 28.2 43% 26% 43% 100% 60% Pueblo Reservoir 186.3 161.9 154.9 354.0 53% 46% 44% 120% 105% Ralph Price Reservoir 16.2 16.2 16.2 100% 100% Ridgway Reservoir 65.4 53.8 68.5 83.0 79% 65% 83% 95% 79% Rio Grande Reservoir 14.2 12.8 10.5 51.0 28% 25% 21% 136% 122% Riverside Reservoir 9.8 3.9 15.2 55.8 18% 7% 27% 64% 25% Ruedi Reservoir 75.7 83.9 93.9 102.0 74% 82% 92% 81% 89% Sanchez Reservoir 5.9 2.5 26.7 103.0 6% 2% 26% 22% 9% Santa Maria Reservoir 11.9 13.7 9.1 45.0 26% 30% 20% 131% 150% Shadow Mountain Reservoir 16.3 17.4 17.2 18.4 89% 94% 93% 95% 101% Silverjack Reservoir 5.3 3.4 6.8 12.8 41% 27% 53% 78% 50% Spinney Mountain Reservoir 43.8 32.6 40.3 49.0 89% 67% 82% 109% 81% Stagecoach Reservoir nr Oak Creek 31.1 34.1 31.8 36.5 85% 93% 87% 98% 107% Standley Reservoir 39.0 35.6 37.6 42.0 93% 85% 90% 104% 95% Taylor Park Reservoir 64.3 72.8 83.2 106.0 61% 69% 78% 77% 88% Terrace Reservoir 3.3 2.9 4.4 18.0 18% 16% 24% 75% 66% Terry Reservoir 4.8 3.1 5.3 8.0 60% 39% 66% 91% 58% Trinidad Lake 26.2 16.0 24.3 167.0 16% 10% 15% 108% 66% Trout Lake Reservoir 2.7 2.6 3.0 3.2 85% 80% 94% 90% 85% Turquoise Lake 81.8 103.1 114.3 127.0 64% 81% 90% 72% 90% Twin Lakes Reservoir 44.1 28.7 61.7 86.0 51% 33% 72% 72% 47% Union Reservoir 11.7 11.3 9.2 13.0 90% 87% 71% 127% 123% Vallecito Reservoir 42.5 54.5 77.7 126.0 34% 43% 62% 55% 70% Vega Reservoir 3.9 5.7 14.0 32.9 12% 17% 43% 28% 40% Williams Fork Reservoir 73.9 86.2 83.6 97.0 76% 89% 86% 88% 103% Willow Creek Reservoir 5.3 7.9 8.2 9.1 58% 87% 90% 65% 96% Windsor Reservoir 4.9 5.3 3.1 15.2 32% 35% 20% 158% 170% Wolford Mountain Reservoir 56.2 59.8 53.4 65.9 85% 91% 81% 105% 112% Yamcolo Reservoir 2.6 2.3 4.3 8.7 30% 26% 49% 61% 53% Basin-wide Total 2962.5 3167.1 3714.7 5956.9 50% 53% 62% 80% 85% # of reservoirs 77 77 77 77 77 77 77 77 77 Current Last Year Average Capacity Current % Last Year % Average % Current % Last Year % IDAHO (KAF) (KAF) (KAF) (KAF) Capacity Capacity Capacity Average Average American Falls Reservoir 221.8 599.6 563.7 1672.6 13% 36% 34% 39% 106% Anderson Ranch Reservoir 197.5 297.7 293.2 450.2 44% 66% 65% 67% 102% Arrowrock Reservoir 62.7 61.6 49.9 272.2 23% 23% 18% 126% 123% Bear Lake 567.2 855.1 635.5 1302.0 44% 66% 49% 89% 135% Blackfoot Reservoir 254.6 167.9 337.0 76% 50% 152% Brownlee Reservoir 1100.7 1205.0 1420.0 78% 85% 91% Cascade Reservoir 409.7 474.4 505.5 693.2 59% 68% 73% 81% 94% Lake Coeur d' Alene 223.9 230.9 238.5 94% 97% 97% Deadwood Reservoir 56.9 75.8 82.4 161.9 35% 47% 51% 69% 92% Dworshak Reservoir 2504.0 2701.0 3468.0 72% 78% 93% Henrys Lake 81.3 81.6 76.9 90.4 90% 90% 85% 106% 106% Island Park Reservoir 58.1 75.5 65.0 135.2 43% 56% 48% 89% 116% Lake Lowell 77.1 88.0 58.4 165.2 47% 53% 35% 132% 151% Little Wood Reservoir 0.1 7.6 8.5 30.0 0% 25% 28% 1% 90% Lucky Peak Reservoir 96.6 242.1 217.5 293.2 33% 83% 74% 44% 111% Mackay Reservoir 1.6 13.1 10.5 44.4 4% 29% 24% 16% 124% Magic Reservoir 9.9 68.1 191.5 5% 36% 15% Mann Creek Reservoir 1.4 4.2 3.0 11.1 12% 38% 27% 45% 140% Montpelier Reservoir 1.8 1.4 4.0 44% 35% 126% Oakley Reservoir 20.2 18.7 75.6 27% 25% 108% Palisades Reservoir 437.5 974.0 845.7 1400.0 31% 70% 60% 52% 115% Lake Pend Oreille 1534.9 1541.0 1561.3 98% 99% 100% Priest Lake 121.8 119.6 119.3 102% 100% 102% Ririe Reservoir 47.1 73.5 58.5 80.5 59% 91% 73% 81% 126% Salmon Falls Reservoir 53.2 38.7 182.6 29% 21% 137% Basin-wide Total 2316.5 3923.7 3474.2 6802.1 34% 58% 51% 67% 113% # of reservoirs 15 15 15 15 15 15 15 15 15 Current Last Year Average Capacity Current % Last Year % Average % Current % Last Year % MONTANA (KAF) (KAF) (KAF) (KAF) Capacity Capacity Capacity Average Average Ackley Lake 3.0 4.0 3.2 7.0 42% 57% 46% 92% 125% Bair Res 2.1 3.8 2.8 7.0 30% 54% 40% 76% 136% Bighorn Lake 831.2 923.7 929.1 1356.0 61% 68% 69% 89% 99% Camas (4) 18.8 45.2 42% Canyon Ferry Lake 1441.3 1650.1 1670.0 2043.0 71% 81% 82% 86% 99% Clark Canyon Res 54.1 98.5 92.7 255.6 21% 39% 36% 58% 106% Cooney Res 16.3 18.9 17.1 27.4 59% 69% 62% 95% 110% Deadman's Basin Res 34.0 54.7 34.0 72.2 47% 76% 47% 100% 161% East Fork Rock Creek Res 4.7 8.1 5.2 16.0 29% 51% 32% 90% 156% Ennis Lake 35.8 38.0 36.3 41.0 87% 93% 89% 99% 105% Flathead Lake 1751.9 1682.6 1758.0 1791.0 98% 94% 98% 100% 96% Fort Peck Lake 13972.8 16008.4 13679.0 18910.0 74% 85% 72% 102% 117% Four Horns Lake 8.8 9.3 19.2 46% 48% 94% Fresno Res 33.2 21.6 44.9 127.0 26% 17% 35% 74% 48% Georgetown Lake 26.5 29.6 28.3 31.0 85% 96% 91% 94% 105% Gibson Res 5.8 18.8 26.8 99.1 6% 19% 27% 21% 70% Hauser Lake & Lake Helena 74.4 74.2 73.5 74.6 100% 99% 99% 101% 101% Hebgen Lake 286.2 346.3 356.3 378.8 76% 91% 94% 80% 97% Helena Valley Reservoir 8.2 7.2 7.1 9.2 89% 78% 77% 116% 101% Holter Lake 80.9 81.2 80.8 81.9 99% 99% 99% 100% 101% Hungry Horse Lake 3279.9 3276.7 3015.0 3451.0 95% 95% 87% 109% 109% Lake Como 6.8 13.6 8.6 34.9 20% 39% 25% 80% 158% Lake Elwell (Tiber) 823.0 837.4 800.5 1347.0 61% 62% 59% 103% 105% Lake Frances 56.4 77.3 57.6 112.0 50% 69% 51% 98% 134% Lake Helena 11.0 11.0 10.9 12.7 87% 86% 86% 101% 101% Lake Koocanusa 5486.4 5318.2 5230.0 5748.0 95% 93% 91% 105% 102% Lima Reservoir 20.0 40.3 28.6 84.0 24% 48% 34% 70% 141% Lower Jocko Lake 0.8 6.4 12% Lower Two Medicine Lake 5.7 6.6 11.9 48% 55% 86% Lower Willow Creek Reservoir 1.7 4.9 34% Martinsdale Res 9.2 15.8 9.2 23.1 40% 69% 40% 100% 172% Middle Creek Res 7.0 6.8 5.7 10.2 69% 67% 56% 123% 119% Mission Valley (8) 32.2 100.0 32% Mystic Lake 17.8 19.5 19.4 21.0 85% 93% 92% 92% 100% Nelson Res 24.9 40.7 31.8 66.8 37% 61% 48% 78% 128% Nevada Creek Res 4.6 6.1 6.1 12.6 37% 48% 48% 76% 100% Nilan Reservoir 5.6