Late last week the Metropolitan Water District of Southern California announced the closure of Diamond Valley Lake (DVL) due to a large blue-green algae bloom that covered the lake.
According to officials, the bloom does not affect the safety or quality of the company’s treated drinking water. The blue-green algae do however produce cyanotoxins which in large concentrations can be harmful to humans and animals, especially when ingested.
Cyanotoxins can cause skin rashes, eye irritation, diarrhea, and/or vomiting in people and animals can experience diarrhea, vomiting, convulsions and/or death. Be sure to call your doctor or veterinarian if you or your animal get sick after going near the water.
As a result, all recreational activities, including boating, fishing and hiking, have been suspended at the lake until further notice. Officials have identified this algae bloom as one the largest ever seen at the lake since it opened to the public for recreation in 2003. Such blooms are caused by naturally occurring organisms that produced large areas of green water and mats of green scum floating on the lake and are common this time of year because of the warm weather.
Metropolitan’s Water Quality Manager, Dr. Mic Stewart was careful to assure the public, “This is a recreation issue, not a drinking water issue.” Yet added, “We don’t want folks coming into contact with or fishing in this water.”
Stewart also assured the public, “We are not using DVL as a drinking water source right now. Even if we did, our processes for withdrawing the water from the lake and treating it will ensure its safety.”
Recreational activities will remain suspended as Metropolitan continues to monitor the blue-green algae bloom and test cyanotoxin levels. According to officials, the suspension will be lifted when conditions improve.
To learn more about Diamond Valley Lake visit www.dvlake.com/. For additional information on cyanobacteria and algae visit www.mywaterquality.ca.gov/monitoring_counil/cyanohab_network.