A lake in Federal Way became the state’s first guinea pig for a chemical that controls algae.

Lake Lorene, located in the Twin Lakes neighborhood, suffers from algal blooms. These colonies of microscopic algae produce harmful toxins and foul odors. The result is detrimental to quality of life for both the ecosystem and surrounding residents.

Factors that lead to excess phosphorus in water can include anything from fertilizer runoff to bodily wastes from ducks and geese.

On Monday, a team of aquatic biologists with Aquatechnex applied a chemical called Phoslock to the 15-acre Lake Lorene. The substance eliminates phosphorus — the primary food source for algae — and restores water quality.

Aquatechnex spread about 9,300 pounds of Phoslock all day long June 11 after receiving the first permit in Washington to use the substance.

The company, which was hired by the Twin Lakes Homeowners Association, will monitor Lake Lorene and record data to measure the treatment’s effectiveness.

Aquatechnex, with offices across the Northwest, has used Phoslock for projects in other states. The permit process in Washington was more complicated because of state-owned waters connected to the project, said director Terry McNabb.

“A lot of times we see the phosphorus go to ‘no detect’ in the same day,” McNabb said. “It’s stunning.”

The Phoslock treatment is more long-term than other methods to treat algal blooms, such as with aluminum sulfate, which tends to alter a lake’s pH, or acidity. If the water’s pH is knocked off balance, any fish in the lake face death. Phoslock does not affect the lake’s acidic balance, according to Aquatechnex’s biologists. Phoslock binds with phosphorus molecules and neutralizes them as the substance sinks to the bottom, mixing with the sediment.

Aquatechnex has contracted with Federal Way to treat Steel Lake and North Lake, including ongoing removal of milfoil, an invasive water plant.

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Pictured below: Aquatechnex biologists apply Phoslock to Lake Lorene on June 11 in Federal Way