The waters in Clear Lake, the second largest in California, shelter a treacherous occupant — potentially toxic blooms of cyanobacteria. The harmful algal blooms are a threat to public health, recreation, and the local economy.
For the 18 public water systems that draw from the lake the noxious blooms are something else: an operating hazard that is complicating their treatment processes and increasing the cost of providing clean water in one of the state’s poorest counties.
