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The Grassy Lake Dam and the Island Park
Reservoir in Idaho were the outcome of an ambitious plan to use the abundant waters of Yellowstone National Park for irrigation in Idaho, Montana and Wyoming. A variety of projects were proposed starting in 1919, the most advanced of which involved a proposed
262:
The dam provides only water storage, impounding 15,200 acre-feet (0.0187 km). Given the small catchment area of Grassy Creek, inflow is augmented by a 0.7-mile (1.1 km) ditch that moves water from
Cascade Creek into the reservoir.
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proposed the withdrawal of the
Bechler area from the park for construction of a reservoir to collect water for use in Idaho. The backlash from conservationists, who compared the proposed reservoir to the
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reservoir in the
Bechler Meadows and Falls River regions of the southwest corner of the park, immediately to the north of the Grassy Lake site. In 1926 Idaho politicians led by Representative
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247:. The dam structure and outlets are within a few hundred feet of the south boundary of Yellowstone. The zoned earthfill dam was built between 1937 and 1939 as part of the
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998:"Conservationists and the Battles to Keep Dams Out of Yellowstone: Hetch Hetchy Overturned"
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Climate data for Grassy Lake, Wyoming, 1991â2020 normals, 1988-2020: 7265ft (2214m)
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The
Yellowstone Story: A History of Our First National Park
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were built outside the park as alternative storage sites.
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1110:Buildings and structures in Teton County, Wyoming
1038:. National Oceanic and Atmospheric Administration
1058:"Grassy Lake, Wyoming 1991-2020 Monthly Normals"
251:, which provides water to irrigate farmland in
16:Dam in Wyoming, near Yellowstone National Park
975:. University Press of Colorado. p. 346.
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1120:United States Bureau of Reclamation dams
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56:Location of Grassy Lake Dam in Wyoming
7:
227:is a small dam operated by the U.S.
243:that runs between Yellowstone and
218:3.65 sq mi (9.5 km)
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239:. The dam lies in a corridor of
208:15,200 acre-feet (0.0187 km)
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919:Source 2: NOAA (Precipitation)
241:Caribou-Targhee National Forest
1130:1939 establishments in Wyoming
235:, immediately to the south of
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267:Bechler Meadows dam proposals
1091:at the Bureau of Reclamation
630:Mean daily minimum °F (°C)
490:Mean daily maximum °F (°C)
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971:Haines, Aubrey L. (1996).
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245:Grand Teton National Parks
179:1,170 ft (360 m)
136:U.S. Bureau of Reclamation
100:44.1309778°N 110.8188250°W
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237:Yellowstone National Park
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105:44.1309778; -110.8188250
171:118 ft (36 m)
116:Construction began
1125:Dams completed in 1939
1016:Cite journal requires
287:Island Park reservoirs
283:Yosemite National Park
279:Hetch Hetchy Reservoir
200:Grassy Creek Reservoir
184:Spillway capacity
700:Mean minimum °F (°C)
420:Mean maximum °F (°C)
233:Teton County, Wyoming
229:Bureau of Reclamation
148:Type of dam
69:Teton County, Wyoming
952:on 26 September 2012
350:Record high °F (°C)
996:Yochim, Michael J.
770:Record low °F (°C)
560:Daily mean °F (°C)
214:Catchment area
205:Total capacity
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914:Source 1: XMACIS2
946:"Grassy Lake Dam"
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88:44°07â˛51.52âłN
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1063:November 21,
1061:. Retrieved
1052:
1042:November 21,
1040:. Retrieved
1030:
1009:cite journal
991:
972:
966:
954:. Retrieved
950:the original
844:inches (mm)
270:
261:
224:
223:
163:Grassy Creek
132:Operator(s)
103: /
79:Coordinates
1099:Categories
927:References
1036:"xmACIS2"
192:Reservoir
1085:Archived
909:(1,328)
840:Average
765:(â31.1)
760:(â28.2)
755:(â23.0)
750:(â13.1)
720:(â16.7)
715:(â23.7)
710:(â27.1)
705:(â27.8)
690:(â14.4)
685:(â10.3)
645:(â10.2)
640:(â13.4)
635:(â13.8)
160:Impounds
65:Location
745:(â5.2)
740:(â1.7)
735:(â0.3)
730:(â3.2)
725:(â9.2)
695:(â5.4)
680:(â4.2)
655:(â1.8)
650:(â6.3)
620:(â9.0)
615:(â4.5)
600:(13.4)
595:(14.2)
575:(â2.8)
570:(â6.8)
565:(â8.3)
550:(â3.6)
535:(17.4)
530:(23.1)
525:(23.6)
520:(17.8)
515:(13.3)
500:(â0.3)
495:(â2.8)
485:(29.2)
475:(10.1)
470:(19.1)
465:(25.1)
460:(28.6)
455:(29.1)
450:(26.1)
445:(21.4)
440:(17.2)
435:(12.9)
293:Climate
197:Creates
71:, near
1003:: 299.
979:
904:(186)
899:(145)
869:(107)
864:(128)
859:(137)
854:(138)
849:(185)
835:(â36)
830:(â35)
825:(â31)
820:(â27)
815:(â11)
795:(â17)
790:(â24)
785:(â32)
780:(â36)
775:(â35)
675:(0.0)
670:(3.8)
665:(4.7)
660:(1.4)
625:(2.0)
610:(2.4)
605:(8.7)
590:(9.6)
585:(5.8)
580:(1.1)
555:(9.3)
545:(1.3)
540:(9.0)
510:(8.3)
505:(4.6)
480:(3.3)
430:(7.0)
425:(3.9)
306:Month
176:Length
168:Height
152:Zoned
1001:(PDF)
956:4 May
907:52.31
894:(94)
889:(57)
884:(39)
879:(30)
874:(82)
810:(â8)
805:(â3)
800:(â7)
763:â23.9
758:â18.8
713:â10.7
708:â16.7
703:â18.1
415:(33)
405:(16)
400:(24)
395:(29)
390:(33)
385:(33)
380:(29)
375:(26)
370:(22)
365:(17)
360:(11)
345:Year
253:Idaho
1065:2023
1044:2023
1022:help
977:ISBN
958:2011
902:7.33
897:5.71
892:3.69
887:2.24
882:1.55
877:1.19
872:3.24
867:4.20
862:5.04
857:5.41
852:5.44
847:7.27
753:â9.4
743:22.6
738:28.9
733:31.5
728:26.3
723:15.4
693:22.3
683:13.5
678:24.5
673:32.0
668:38.8
663:40.4
658:34.6
653:28.8
648:20.7
643:13.6
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618:15.8
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608:36.4
603:47.7
598:56.2
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588:49.3
583:42.4
578:33.9
573:26.9
568:19.7
563:17.0
553:48.8
548:25.6
543:34.3
538:48.2
533:63.4
528:73.5
523:74.5
518:64.0
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483:84.6
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468:66.3
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458:83.5
453:84.3
448:78.9
443:70.6
438:62.9
433:55.2
428:44.6
423:39.0
410:(8)
355:(9)
342:Dec
339:Nov
336:Oct
333:Sep
330:Aug
327:Jul
324:Jun
321:May
318:Apr
315:Mar
312:Feb
309:Jan
127:1939
119:1937
833:â32
828:â31
823:â24
818:â17
788:â12
783:â25
778:â32
773:â31
748:8.5
718:2.0
688:6.1
638:7.9
633:7.2
281:in
255:'s
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