Island County commissioners are considering a different way to address toxins found within Whidbey lakes.

Much of the recent conversation among county officials centered around Lone Lake, a South Whidbey body of water outside of Langley city limits continuously afflicted by toxic algae blooms that can make humans and animals sick. It is not uncommon to see signage posted at the access point warning visitors of the harmful toxins, especially during the warmer summer months.

Rather than pursuing costly phosphorus treatment for just Lone Lake, Public Health officials are recommending applying for state grant funding for control of invasive species of aquatic plants, which also affects Lone Lake. The Ecology Freshwater Algae Program Grant totals $50,000, which is only about 20% of what is needed to treat Lone Lake; officials estimate that it would take five years and $250,000 to fully treat Lone Lake.

Mark Systma, chairperson of the county’s Noxious Weed Control Board, has urged that even one year of phosphorus treatment in Lone Lake would be better than none at all. He spoke during the public comment section of the county commissioners’ regular meeting last week, pointing out that toxins were detected almost 9,000 times the amount safely allowed under the state recreational guidance.

The topic was discussed the next day during a work session. In a memo to the commissioners, Public Health Director Shawn Morris and Natural Resources Manager Jennifer Schmitz wrote that the general lakes monitoring program is the critical first step to understanding the full scope of the issue, and it provides the data needed to justify and plan future treatment. Cleaning up aquatic invasive plants directly supports water quality and habitat improvement, which are contributing factors to the recurring algae blooms.

On the other hand, they recommended delaying phosphorus treatment, pending further data collection and program development.

Hydrogeologist Chris Kelley said the Public Health recommendations align with the Lone Lake management plan that was produced by the Whidbey Island Conservation District a few years ago. One of the things the conservation district has pointed out is the importance of getting a better idea of what nutrients are coming into the lake.

“Whether it’s from fertilizer, septics, we don’t know yet, but that’s what needs to be addressed before jumping into treatment,” he said.

The introduction of herbicide and carp that were used to get rid of an exotic water plant ended up harming native plants, shifting the lake to become dominated more by algae.

The commissioners expressed some confusion about which entity should be responsible for Lone Lake, and if it should really be the county.

“I was under the impression that this was not our lake,” Commissioner Jill Johnson said.

Similarly, Commissioner Janet St. Clair said she was supportive of the citizens’ concerns about Lone Lake, but that she wasn’t sure if it was the county’s issue. She was critical of there being no plan to mitigate runoff of nutrients, despite past conversations.

Morris and Schmitz said there is different ownership around the lake, including private property owners. The county does have an access point, but Schmitz said it might not be the best place to monitor water quality. There was some discussion about how the state owns the waters. South Whidbey Parks and Recreation District has an agreement with the Department of Fish and Wildlife, which owns the park, to maintain the landscaping and service the restrooms.

The county currently lacks a harmful algal bloom testing or monitoring program, and other lakes across Whidbey could benefit from the establishment of one. Yet the commissioners did not seem too keen on the idea. Johnson questioned if now is the right time to start a new program.

In the end, the commissioners decided not to pursue grant funding for either the general lakes program monitoring nor the phosphorus treatment for Lone Lake. Instead, they decided to pursue it for control of the invasive aquatic plants in multiple lakes across Whidbey.

In an email to The Record, Seth Luginbill, the county’s Noxious Weed Program coordinator, said staff have found fragrant water-lily and yellow flag iris in Lone Lake.

“When these weeds grow out of control, they impact water quality, clog the lake, and crowd out the native plants that belong there,” Luginbill said.

Previous infestations of hairy willow herb in Crockett and Swantown lakes were successfully eradicated. Cranberry Lake has had a record of small infestations of purple loosestrife and hairy willow herb but these are actively being managed by the park, he said. Goss Lake has an infestation of yellow flag iris, but local community members have been controlling this on their own.

The commissioners also directed Public Health staff to research state-funded opportunities for toxic algae treatment for local lakes and add research into a lake monitoring program to the department’s 2026 work plan, with a goal of a 2027 grant application.