Alum treatment taking place next week

Doses of alum will be applied to the Main Lake, East Bay and the North Ski Area of Canyon Lake beginning Monday and wrapping up on Friday, The Lake Elsinore and San Jacinto Watersheds Authority (LESJWA) said.

The water authority will be spraying the treatment from its boat as it covers the predetermined areas of the lake, which will remain open during the entire treatment process. Recreational users will experience little disruption during treatment application and implementation.

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 aquatic life, Mark Norton, Authority Administrator of the LESJWA, said. Drinking water quality will not be affected by any of the treatment options. Canyon Lake will remain open during the entire treatment process.

Photos provided by Lake Elsinore & San Jacinto Watersheds Authority

Alum binds with phosphorus in the lake water, drops the nutrient to the lake bottom and thereby reduces algae growth in the lake, Mark said.

“Canyon Lake water mostly comes from stormwater runoff from the upper watershed each year that has high levels of nutrients that hurt water quality and threaten aquatic life,” Mark said. “This dose reflects a continuance of alum application to Canyon Lake, typically applied twice a year, similar to previous years.”

Photos provided by Lake Elsinore & San Jacinto Watersheds Authority

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, a coalition of cities, the county and several other organizations led by LESJWA, provides funding to continue alum water treatments in Canyon Lake.

The TMDL Task Force evaluated several options during the CEQA process 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, Mark said.

The application process will occur each day next week from 7:00 a.m. to 4:00 p.m.

Photos provided by Lake Elsinore & San Jacinto Watersheds Authority

The Main Lake will receive its treatment on Monday and Tuesday. The Main Boat Ramp to the west end of East Bay will be treated on Wednesday and the rest of East Bay will be treated on Thursday. The final day of the treatment will take place on Friday and will cover the North Ski Area.

For daily operational updates, Canyon Lake residents can visit http://www.canyonlakealum.wordpress.com/.