Friends of Vancouver Lake announces treatment date for Eurasian milfoil weed

Vancouver, WA – Treatment of the Eurasian watermilfoil weed infestation in Vancouver Lake and the flushing channel has been scheduled for Tuesday, July 7. The planned treatment is expected to take 1-3 days and will not affect Lake users nor limit activities. Eurasian Watermilfoil (EWM) is a class B noxious weed in Washington that requires mandatory control. EWM forms dense mats underneath the surface of the water and left untreated, can quickly alter the ecosystem of a body of water threatening lake users, animals, and native species of plants and aquatic life.

The presence of EWM was first identified in spring 2018 by regular Lake users – primarily members of the Vancouver Lake Rowing Club and the Vancouver Lake Sailing Club who became alarmed as they noted widespread infestation and expansion into rowing, sailing, and swimming areas. These citizens determined that without effective treatment, EWM would cover the Lake by 2021.

EWM spreads through fragmentation and exists in many bodies of water throughout the state. Fragmentation occurs by fish movements in shallow water, by swimmers or animals that become entangled in the weed, and by contact with boats, paddles, oars. Absent effective treatment and management, EWM returns annually and in greater numbers. FoVL, the Department of Ecology, the Department of Fish and Wildlife and Clark County weed control will monitor effectiveness of the treatment and continue to survey the Lake for signs of new growth which must be addressed. Future management and treatment will occur through the County’s newly-minted Integrated Aquatic Vegetation Management Plan (IAVMP). FoVL participated extensively in development of the plan and will continue to support observation and treatment as part of its commitment to restoration of the Lake.

FoVL formed in in late 2018, after finding no efforts to control EWM by local agencies. The group joined with representatives of the rowing and sailing clubs to immediately begin working with local agencies, SW WA legislators, and the state Department of Ecology to apply for a permit to treat EWM as a private group.

Through dogged determination and the support of many allies, FoVL and the rowing club ultimately gained approval to use newly-approved ProcellaCOR to treat the Lake’s EWM. FoVL also began extensive fundraising efforts gaining support from hundreds of Clark County citizens and significant donations from the Firstenburg Foundation and the Ed and Dollie Lynch Foundation as well as contributions from Clark County and the Port of Vancouver USA. Treatment costs are estimated at $150,000 to $200,000 this year. Cost variables include acreage affected and water depth at the time of treatment.

The treatment method to be used utilizes ProcellaCOR which was approved for use by the state Department of Ecology in 2019 and approved by the U.S. EPA as a reduced-risk herbicide with significantly reduced risk to the environment and human health. It is selective and systemic and has an extremely short contact exposure time requirement, an affinity for target species like Eurasian milfoil, moves into the plant rapidly and can be effectively applied in the very low parts per billion range. In addition, ProcellaCOR has very minimal water use restrictions; it can be applied to potable water supplies with no restriction on the use of treated water for that purpose. It has no swimming or fishing restriction.

FoVL had previously planned to treat EWM in the summer of 2019 but rapidly deteriorating plant conditions halted the effort. Current conditions show optimal plant size and reasonable water levels. EWM in the Port-owned flushing channel will be treated as well ensuring effectiveness of the Lake treatment. Port commissioners voted to financially support treatment and Port staff helped ensure access to the channel.

FoVL is enormously grateful for the support of community members who understand the unique beauty and importance of Vancouver Lake in SW WA for public recreation, competitive rowing, sailing, dragon boating and much more and have generously donated financially to EWM treatment. We are proud that treatment will be completed soon and that the Lake will be accessible to all users. We also recognize that in the long term, water quality of the Lake must be improved and will continue to work on issues of water quality with local government, legislators and state agencies to develop a lake management plan that will insure that this precious resource in our community will be preserved and protected.

For all inquiries, please contact FoVL Co-Chair Larry Cassidy at 1-360-798-1249 and or co-chair Kathy Gillespie at 360-901-6538 and