Canyon Lake alum application to begin next week


Alum application treatments are scheduled for Canyon Lake next Monday through Friday, September 26 to 30. The upcoming alum treatment doses will remain the same as previous applications to the Main Lake and East Bay coves. A newly added section of the lake receiving the alum will be the area north of the causeway known as the North Ski Area.

Starting early Monday morning, trucks filled with alum will be prepared for the week-long applications. With the addition of adding doses to North Ski Area, five additional trucks of alum will be used. Prior to the application, water samples will be tested for dissolved oxygen, pH and temperature to confirm appropriate water quality conditions – a procedure that is always followed prior to beginning the treatment process.

The alum treatments are in no way connected to the recent algal blooms or lake closure in August. Additionally, drinking water quality is not affected by the alum applications. The Lake Elsinore and San Jacinto Watersheds Authority (LESJWA), an organization that aims at improving water quality and the ecology of Canyon Lake, is responsible for coordinating the ongoing alum treatments in Canyon Lake. The September application will be the seventh time the alum has been applied to the lake.

“Because Canyon Lake is located at the end of the watershed, the lake receives an excess of nutrients, some of which can be harmful to the overall water quality and threaten marine life,” says Mark Norton, LESJWA administrator. “Since 2013, LESJWA has been monitoring the effectiveness of the alum applications. Following study results, announced this past June, findings proved that the treatments have been effective in lowering levels of phosphorus in comparison to findings from 2009-2012. Algae feed on phosphorus. If we are able to minimize phosphorus, we can minimize algae.”

Because alum has been proven as an effective method to treat phosphorus, as well as safe for humans and marine life, it has continued as the preferred treatment to improve water quality in Canyon Lake. Minimal disruption will take place for lake recreation.

During the application, sections of the lake being sprayed will be blocked off; however, access will be open immediately following. To view live project updates, residents can visit

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 have been provided by a State grant, the Santa 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.

Treatment Plant Improvements

In other news, the Elsinore Valley Municipal Water District (EVMWD) took another step towards drought-proofing its service area by harnessing more of its local water supplies through improvements to its drinking water treatment plant.

The Canyon Lake Water Treatment Plant, located on the south side of Canyon Lake, supplies about 10 percent of EVMWD’s drinking water. The aging system was in need of several upgrades to maximizes its production potential.

Over the summer, EVMWD rehabilitated the aging clarification system at the plant, allowing for drinking water to be treated more efficiently and allow for increased reliability. The Canyon Lake Water Treatment Plant will now produce approximately 2.5 to 3 million gallons of water daily, lessening the demand for imported water from Northern California and the Colorado River. Water from the Canyon Lake Water Treatment Plant is blended with supplies of ground water and imported water and distributed throughout the EVMWD service area.

“We are always looking for ways to save our ratepayers money,” says Phil Williams, president of the EVMWD board of Directors. “By making these improvements to our local infrastructure, we reduce the need to purchase expensive imported water.”

Customers may notice a subtle aesthetic change in their drinking water initially. Drinking water captured in local reservoirs, such as Canyon Lake, from rainfall can naturally develop tastes and odors. These are typically caused by different types of naturally occurring algae and minerals. Though on occasion, these variations may cause a change in taste or odor, customers can be assured the water meets the highest standards for drinking water.