Residents invited to learn about alum treatments


Canyon Lake is about to receive its fifth and final alum treatment in the initial program of treatments planned over the past two-and-a-half years. The treatment is scheduled for September 21 to 24.

Before then, Canyon Lake residents are invited to a public information and outreach meeting on September 9, featuring a panel experts including Dr. Michael Anderson from the University of California Riverside, who has been studying the effects of the alum treatments in Canyon Lake. Residents will learn how the overall quality and clarity of the water has improved and will be able to ask questions. The meeting will begin at 7 p.m. in the City Council Chamber.

Others on the panel include Jason Uhley of the Riverside County Flood Control and Water Conservation District; Mark Norton, administrator of the Lake Elsinore & San Jacinto Watersheds Authority (LESJWA); Timothy Moore, Risk Sciences; and Brian Dickinson, EVMWD Operations Manager.

“The meeting is designed to encourage community involvement and keep Canyon Lake residents informed,” says City Manager Ariel Hall. “We welcome residents to take an interest in what happens in Canyon Lake and hear more from the panel of experts.”

The Lake Elsinore and Canyon Lake Total Maximum Daily Load (TMDL) Task Force says it has made significant strides in improving water quality in Canyon Lake through alum treatment applications.

Following the fifth alum treatment, a preliminary report will be compiled to suggest next steps in improving conditions in Canyon Lake. The TMDL Task Force says that, while algae cannot be entirely eliminated, the alum applications have been proven effective and possible future alum treatments will likely be suggested.”

Mark Norton summarizes how the alum treatments work by saying, “Historically, Canyon Lake has been known to suffer from algae blooms. Because of nitrogen and phosphorus that enters the lake through water runoff, the lake suffers from an excess amount of nutrients. These nutrients encourage algae growth. When the alum is added to the lake, it immediately binds to the phosphorus, which reduces the opportunity for algae growth.”

In order to comply with water quality regulations enforced by the State through the local Santa Ana Regional Water Quality Control Board, the TMDL Task Force has been using a state-funded grant to continue alum water treatments in Canyon Lake.

The 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.

Funding for the alum applications has been provided by a state grant and by the 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.

LESJWA is a joint powers authority entrusted with state and local funds to improve water quality and wildlife habitats in Lake Elsinore, Canyon Lake and the surrounding San Jacinto watershed. For more information about LESJWA, visit


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Donna Ritchie