Are city efforts to treat toxic algae at this Pierce County lake working? What we know

or years a green film covered Waughop Lake in Fort Steilacoom Park, the result of decades of manure, agricultural waste and sewer dumped there as far back as 1900.

Although toxic algae no longer scums the surface of the shallow body of water, is the water safe? A longtime resident who has advocated for better management of the lake remains skeptical, so The News Tribune asked the city of Lakewood about what it has done to treat the lake in recent years.

During a Tuesday visit to the lake at 8714 87th Ave. SW, the water looked blue and murky, and a sign posted by the Tacoma-Pierce County Health Department urged visitors to ‘Watch out for toxic algae!’, keep their dogs away from the water and not to swim or boat near algae blooms.

The city said a farm operated by nearby Western State Hospital dumped manure and other agricultural waste into the lake between 1900 and 1965. That contributed to a buildup of loose, nutrient-rich sediments that fueled algae growth and toxic cyanobacteria blooms that caused the health department to issue advisories between 2008 and 2018. No creeks or other natural surface waters flow into the lake, according to a report published in February.

In 2020 and again in 2023 the city treated Waughop Lake with aluminum sulfate to remove phosphorus from the water and inactivate phosphorus in the sediment, Lakewood said in an article about the topic published this week. The treatments, which the city says are common practice in lake management and don’t result in long-term impacts to pH or alkalinity in water, “dramatically reduced” phosphorus availability in the lake.

“They prevented toxic algae blooms in 2020, 2021, 2023 and 2024, even with elevated chlorophyll concentrations (the amount of algae in the lake) in late 2023 and throughout 2024,” according to the city. “Because of the alum treatments, Waughop Lake has not experienced a toxic algae bloom for the first time in over a decade. Detections of cyanotoxins are below state recreation guidelines.”

Don Russell, 95, is a longtime Lakewood resident who studied aquatic and fishery science at the University of Washington in 1953 and has been monitoring the lake on his own since the 1990s.

Russell has been outspoken at City Council meetings about how he believes the city’s aluminum-sulfate treatments were “unprecedented” in their dosage and killed off aquatic plant growth, fish and frogs, which he says has resulted in abandonment of waterfowl at the lake. He’s also concerned that although the scum has visibly gone, toxic cyanobacteria could still remain.

“They claim [Waughop Lake] to be the crown jewel of Fort Steilacoom Park. You go and look at it, it’s a chartreuse green, you can’t see down more than about two feet,” Russell said. “There’s signs posted that say, ‘Warning: potential toxic algae blooms.’ And that’s hardly an invitation to go there and recreate and enjoy and have a spiritual experience. … To leave it in its present state is criminal.”

City spokesperson Brynn Grimley told The News Tribune on Wednesday that aquatic life has returned to the lake, including turtles and migrating birds. Upon a visit Tuesday, a News Tribune reporter observed a couple mallards on the lake.

Grimley said Thursday the physical nature of the lake is not conducive to all aquatic life due to its shallowness and loose and thick bottom layer. City staff also said Waughop Lake has been tested for cyanobacteria, and, as of May 13, 2024, toxins were not detected, according to lab results sent to The News Tribune.

Russell’s claims that the city “created a toxic cesspool of aluminum” and used an “unprecedented” dosage of alum is not true, Grimley said.

According to a data report published in February and presented to the city by Tetra Tech, Inc., which applied the aluminum-sulfate treatments, the company applied two higher dose applications of alum in 2020 and a third lower dose in 2023.

“Alum is a widely used chemical in wastewater and drinking water treatment facilities to clarify and remove impurities from water. In lakes, alum has been one of the most successfully implemented and effective in-lake treatments to reduce internal loading of phosphorus and remove phosphorus from the water column,” Tetra Tech said in the report.

It was recommended to use alum treatments that were “three to six times greater than the average lake dose for the Puget Sound region ... based on the high sediment phosphorus concentrations,” according to the report.

Russell has proposed the city alter the water chemistry or dredge the lake to make it more habitable for aquatic plants, which would in turn support other creatures higher up in the food chain.

Grimley said Lakewood looked into dredging the 33-acre lake in 2018 to remove the phosphorus-rich bottom sediments instead of treating the lake with an alum solution, but it was determined to not be financially feasible.

At the time it would have cost the city up to $35 million to dredge Waughop Lake, likely much more today, Grimley said. For context, in 2018 the city of Lakewood spent a total of about $37.5 million on general fund expenditures,

Grimley said if the city took that route up to 50 acres of Fort Steilacoom Park would have to be closed for years in order to dry out the sediments. The sediment could have arsenic in it, which would be considered hazardous, and the city would not be able to sell it as fertilizer, she said.

“The smell would be beyond disgusting. So now you’re impacting all those homes that border the park with this rancid smell,” Grimley said. “Plus the million-plus visitors to the park will be dealing with the smell, they’re not going to be able to access this giant field — we use it for parking for our events. Realistically, it just was not going to work.”