Alum application set to begin Monday


As part of a continuing effort to improve Canyon Lake’s water quality, the Lake Elsinore and San Jacinto Watersheds Authority (LESJWA) will continue alum treatments to Canyon Lake in the Main Lake, East Bay and North Ski Area between May 16 to 20.

According to LESJWA spokesperson Mark Norton, stormwater runoff carries high levels of nutrients, including nitrogen and phosphorus, that hurt water quality and threaten marine life. “Past alum treatments have resulted in remarkable water quality improvement trends,” he says.

Alum, the method selected to provide the best results for Canyon Lake, has a proven track record of success and is safe to both humans and marine life. Drinking water quality will not be affected by any of the treatment options. Recreational users will experience little disruption during treatment application and implementation.

Certain areas of the lake will be blocked off during the applications process, which should last only a few hours. Boats will have full lake access immediately after the application process is completed.

Some beach areas might be briefly closed off during the alum application, but access will be open immediately once the application process is completed. Swimmers will be able to safely enjoy the lake immediately after the application process is complete.

In order to comply with water quality regulations, enforced by the State through the local Santa Ana Regional Water Quality Control Board, the Lake Elsinore and Canyon Lake Nutrient Total Maximum Daily Load (TMDL) Task Force continues to conduct alum water treatments in Canyon Lake. The TMDL Task Force evaluated several options and determined that alum application provides the best option as a step to effectively treat the entire lake in a timely manner with minimal impact to Canyon Lake residents.

Funding for the alum applications has been provided by a State grant, the Santa Ana Watershed Project Authority–One Water One Watershed, and by the Lake Elsinore and Canyon Lake Total Maximum Daily Load (TMDL) Task Force, which consists of cities, the County of Riverside, agriculture and dairy coalitions and other organizations in the San Jacinto River watershed.

Implementation of the alum project is being coordinated by the City of Canyon Lake, the Elsinore Valley Municipal Water District, LESJWA, the TMDL Task Force and the Canyon Lake Property Owners Association.

A 2015 Canyon Lake Alum Application video can be viewed at

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