Tincture Could Be the Cure for Salton Sea Algae

A 50-year-old chemical treatment may remedy the problem of increased algal blooms in the Salton Sea.

A study released Friday suggested that adding aluminum sulfate to two of the lake’s tributaries could help neutralize phosphates flowing into the sea and cut down on algae growth.

The problem facing California’s largest lake in the desert northeast of San Diego is called eutrophication, by which nutrients in the water create an environment conducive to algae growth.

Such growth, however, can change the chemistry of the water and cause massive fish die-offs and noxious odors.

“The question of eutrophication at the sea is a complex one,” said Tom Kirk, executive director of the Salton Sea Authority. The authority commissioned the study and plans to conduct limiting testing of its conclusions later this year.

“Think of it as building houses,” said Jim Setmire, a hydrologist with the U.S. Geological Survey. “In this case, nitrates are the wood and phosphates the nails. We are attempting to limit the number of eutrophic houses by taking away the nails.”

In fact, aluminum sulfate has been used to control algal blooms since the 1950s. But it has never been tried at the Salton Sea.

Because the lake is so large, direct treatment with aluminum sulfate would be difficult. But the study suggests that treating the New and Alamo rivers--which feed into the lake--could help cut back phosphates.