Largest Reservoirs in Wyoming

Wyoming has 1372 dams with recorded storage capacity. The largest is Boysen Dam with 1,473,118 acre-feet of maximum storage. One acre-foot equals about 326,000 gallons — enough to supply roughly two households for a year.

#	Dam	County	Max Storage (acre-ft)	Height (ft)	Purpose	Year
1	Boysen Dam	Fremont	1,473,118	220	Flood Risk Reduction	1952
2	Glendo Dam	Platte	1,118,653	196	Flood Risk Reduction	1958
3	Glendo Dike 2	Platte	1,118,653	63	Flood Risk Reduction	1959
4	Glendo Dike 3	Platte	1,118,653	94	Flood Risk Reduction	1959
5	Seminoe Dam	Carbon	1,017,279	295	Hydroelectric	1938
6	Pathfinder Dam	Natrona	1,016,500	214	Hydroelectric	1909
7	Pathfinder Dike	Natrona	1,016,500	38	Fish and Wildlife Pond	1911
8	Jackson Lake Dam	Teton	872,700	84	Flood Risk Reduction	1911
9	Buffalo Bill-diamond Creek Dike	Park	646,565	136	Fish and Wildlife Pond	1905
10	Buffalo Bill-north Fork Dike	Park	646,565	30	Fish and Wildlife Pond	1905
11	Keyhole Dam	Crook	629,025	168	Flood Risk Reduction	1952
12	Fontenelle Dam	Lincoln	334,411	139	Fish and Wildlife Pond	1964
13	Lake Desmet (north Dam)	Johnson	234,987	120	Water Supply	1975
14	Lake Desmet (south Dam)	Johnson	234,987	120	Water Supply	1975
15	Lake Desmet (a,b,c & Spillway Dikes)	Johnson	234,987	120	Water Supply	1975
16	Grayrocks	Platte	194,000	95	Other	1980
17	Alcova Dam	Natrona	184,405	265	Hydroelectric	1938
18	Bull Lake Dam	Fremont	163,976	81	Flood Risk Reduction	1938
19	Wheatland No. 2	Albany	144,877	37	Irrigation	1901
20	Lake Hattie	Albany	130,182	43	Irrigation	1912
21	Woodruff Narrows	Uinta	102,000	68	Irrigation	1962
22	Wheatland No. 3	Albany	100,271	28	Irrigation	1964
23	Lower Sunshine	Park	71,800	162	Irrigation	1972
24	Upper Sunshine	Park	65,100	160	Irrigation	1942
25	Big Sandy Dike	Sweetwater	54,400	22	Flood Risk Reduction	1952
26	Big Sandy Dam	Sweetwater	54,400	85	Flood Risk Reduction	1952
27	Greybull Valley (1st Enl.)	Park	53,200	207	Irrigation	2000
28	Guernsey Dam	Platte	45,612	137	Hydroelectric	1927
29	Rob Roy	Albany	42,264	150	Water Supply	1986
30	James Lake	Albany	41,100	40	Irrigation	1908
31	Lower Snake Draw (4th Enl.)	Sweetwater	38,938	85	Tailings	1998
32	Meeks Cabin Dam	Uinta	38,720	185	Irrigation	1971
33	Boulder Lake	Sublette	37,800	25	Irrigation	1964
34	Pilot Butte Embankment 3	Fremont	36,900	12	Irrigation	1926
35	Willow Lake	Sublette	32,125	20	Irrigation	1955
36	High Savery	Carbon	30,387	165	Irrigation	2003
37	Bush Creek	Sweetwater	28,290	22	Irrigation	1945
38	Laprele	Converse	26,850	135	Irrigation	1909
39	New Fork Lake	Sublette	25,700	37	Irrigation	1925
40	Hog Park Main Dam	Carbon	24,987	118	Water Supply	1986
41	Hog Park Saddle Dam No. 1	Carbon	24,987	26	Water Supply	1986
42	Hog Park Saddle Dam No. 2	Carbon	24,987	34	Water Supply	1986
43	Hawk Springs	Goshen	24,500	64	Irrigation	1925
44	Glendo Dike 1	Platte	23,320	50	Flood Risk Reduction	1959
45	Anchor Dam	Hot Springs	22,390	208	Irrigation	1960
46	Fmc Granger Tailings Pond Phases 1e -1j	Sweetwater	21,800	28	Tailings	2013
47	Sulphur Creek	Uinta	19,775	85	Irrigation	1964
48	Texas Gulf Tailings (phase 1e & 1f Enl.)	Sweetwater	19,263	30	Other	1976
49	Grassy Lake Dam	Teton	16,210	118	Irrigation	1939
50	Eden West Dike	Sweetwater	14,421	25	Irrigation	1907

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