LakeCount. Every Lake. Measured.

Lakes / Washington / Halfmoon Lake

Halfmoon Lake, Adams County, Washington

25 acres
Surface Area
825 ft
Surface Elevation

Where It Sits, and How Deep It Goes

Locator - Washington

OlympiaSeattleHalfmoon LakeAdams Co.

46.89 degrees N, 119.24 degrees W - Adams County. State and county outlines drawn from Census boundary data; the lake marker is placed by its Washington DFW coordinates, not by eye. Schematic - not a survey map.

Facts and Figures

Waterbody ID{8E221F9C-78EE-4C07-97D8-11138E4F5004}
CountyAdams
Lake TypeLake
Coordinates46.8936, -119.2408

Largest Lakes in Washington

#LakeCountySurface AreaMax Depth
1Franklin D Roosevelt LakeFerry71,323 acres-
2Lake UmatillaKlickitat50,042 acres-
3Lake ChelanChelan32,677 acresAbout 1,500 ft
4Banks LakeGrant26,879 acres-
5Lake WallulaBenton26,343 acres-
Sources: USGS NHD via WA Dept of Ecology lake data (ID {8E221F9C-78EE-4C07-97D8-11138E4F5004}). Verified October 30, 2026.