LOCATION.--Lat 43° 51'33", long 110° 35'23", in SE1/4 SW1/4 sec.18, T.45 N., R.114 W., Teton County, Wyoming, Hydrologic Unit 17040101, Moran quad., Grand Teton National Park, at Jackson Lake Dam on Snake River, 4.3 mi west of Moran, Wyoming, and at mile 988.9.

DRAINAGE AREA.--807 mi².

PERIOD OF RECORD.--July 1908 to September 1979, (1908-10 fragmentary), October 1984 to September 2000 (discontinued). Prior to October 1968, published as "at Moran". Since October 2000, gage operated by U.S. Bureau of Reclamation.

REVISED RECORDS.--WDR Idaho 1974: Drainage area.

REMARKS.--Reservoir was formed by log crib dam built in the outlet of the natural lake in 1906. Usable capacity was 300,000 acre-ft. This dam washed out in July 1910 and was replaced by an earth dam, forming a reservoir with a usable capacity of 380,000 acre-ft. The earth dam was raised in 1916, increasing the usable capacity to 790,000 acre-ft. In 1917, by dredging the outlet, the usable capacity was further increased to 847,000 acre-ft between elevations 6,730 ft (top of baffles to sluices) and 6,769 ft (top of spillway gates). The dam was rebuilt during 1987-89, with the usable capacity remaining the same. Reservoir is used to store water for irrigation in Snake River Valley, Idaho. Figures given represent usable contents.

COOPERATION.--Reservoir elevations and capacity table provided by U.S. Bureau of Reclamation.

EXTREMES FOR PERIOD OF RECORD.--Maximum contents, 874,100 acre-ft June 11, 1997, elevation, 6,770.06 ft; no usable contents for several days during period August to October 1919.