Data sources

Each lake page links to the agency record and identifies the station, series, measurement type and water-surface reference. We reviewed the source and its reuse terms before including it.

United States Geological Survey

The site uses 91 USGS series. USGS Water Data APIs supply provider daily means. Approved, provisional and revised qualifiers are retained; estimates and other excluded qualities do not silently become measured values.

US Army Corps of Engineers

Nine series use the CWMS Data API. These daily observations retain their provider convention and are not relabelled as daily means or assigned an invented USGS approval status.

Reuse and attribution

Each lake’s CSV download includes the source details for its observations. Agency records can be incomplete or corrected later, so consult the linked source for context. No government agency endorses this site.