LOCATION.--Lat 43° 34'42", long 116° 44'28", in NW1/4 SE1/4 sec.19, T.3 N., R.3 W., Canyon County, Hydrologic Unit 17050114, Lake Lowell quad., on outlet structure at lower embankment, 5.5 mi southwest of Caldwell; and Lat 43° 33'30", long 116° 38'55", on outlet structure at upper embankment 5 mi west of Nampa.

PERIOD OF RECORD.--October 1917 to September 1978 (discontinued). Prior to October 1945, published as Deer Flat Reservoir near Caldwell.

GAGE.---Nonrecording gage. Datum of gages is 2,500.5 ft above NGVD of 1929, levels by US Bureau of Reclamation.

REMARKS.--Reservoir is formed by two earth embankments; dams were completed and storage began in 1908. Capacity, 177,150 acre-ft, between gage heights 0.0 ft, sill of outlet gates and 30.0 ft, maximum operating level. Dead storage, about 13,000 acre-ft. Below gage height 12.0, lake divides into two pools. Lake receives water from Boise River through New York Canal of Boise project and small amounts from local drainage. Water is used for irrigation of lower project lands, some of which are outside the Boise River basin. Figures given represent usable contents.

COOPERATION.--Gage readings and capacity table furnished by Water District 63.

EXTREMES FOR PERIOD OF RECORD.--Maximum contents observed, 178,900 acre-ft Apr. 27, 28, 1922, Apr. 24, 1932, gage height, 30.18 ft; minimum observed, 5,390 acre-ft Oct. 22, 1924, gage height, 3.27 ft, upper pool; 0.85 ft, lower pool.