Imperial County Lake Quality

Imperial County has 12 monitored lakes — a thin enough sample that one or two stressed lakes can move the county average noticeably. Use the per-lake pages below for what actually matters. 1 of those lake carry recent nutrient and algae readings. The county-level summary describes that subset, not every water body listed. Most monitored lakes in Imperial County are productive, shallow basins; each lake page shows its own phosphorus and chlorophyll-a readings beside the EPA condition class.

Most of the county's monitored lakes are shallow, under 50 feet, which means wind keeps the water column mixed all summer and sediment-bound phosphorus releases back into the surface layer whenever the bottom is disturbed. Salton Sea Lake has the lowest nutrient and algae readings in the county.