Treatment targeting harmful algae at Vancouver Lake Regional Park is scheduled for Thursday, July 25, 2024.

AquaTechnex, a lake and aquatic plant management firm with expertise in managing harmful algal blooms, will apply an aquatic algaecide to the water at the Vancouver Lake swim beach. Boats will be used to apply the algaecide, which is designed to target and kill cells in harmful algae.

The application will begin at about 11 am Thursday and is expected to take about two hours, during which the swim beach will be closed to the public. Algae has been observed in the water column at the swim beach. When algae die, it releases cyanotoxins. It’s unclear whether the treatment will cause toxin levels to exceed threshold levels recommended by the Washington Department of Health. As a precaution, Clark County Public Health is issuing a warning advisory for the swim beach, pending test results from water samples collected after treatment.

While a warning advisory is in place, Public Health advises against swimming or water skiing in the lake and recommends avoiding areas of scum when using motorized boats, paddle boarding, kayaking or canoeing. Fish should be cleaned well, and organs should be discarded. 

When applied in water, the algaecide targets the algae cells and then breaks down after treatment into water and oxygen. The algaecide does not pose a risk to people and pets, or cause harm to other plants, birds, fish and wildlife when applied according to the directions on the label. As a reminder, dogs and other domestic animals – except for service animals – are not allowed on the beach or surrounding grassy area of Vancouver Lake Regional Park between April 1 and Oct. 31.

Vancouver Lake Management Plan
In August 2023, Clark County completed the Vancouver Lake Management Plan, aiming to develop a long-term plan to restore and maintain the health of Vancouver Lake. This year, Clark County was awarded a $330,000 legislative proviso to implement recommendations from the management plan. One recommendation within the plan was to implement a beach management plan for the Vancouver Lake swim beach.

Clark County’s Clean Water Division is working closely with Clark County Parks and Lands Division, Clark County Public Health and Herrera Environmental Consultants – with input from community stakeholders through the Vancouver Lake Technical Advisory Group – to develop and implement a beach management plan, which includes the algaecide treatment. Additional algae treatments are expected to occur this summer.

For more information, visit the Vancouver Lake Management Plan Project webpage.