Mysterious Green Foam Spews from Drain in Utah

Though results of samples taken from the drain are pending, Nicholas Rupp from the Salt Lake County Health Department told KSL-TV that the foam most likely came from a nearby canal's recent moss treatment — and isn't related to the lake's slimy bloom. The chemicals used to clear canals of moss also foam up, Rupp said.
Donna Spangler, communications director for the Utah Department of Environmental Quality (Utah DEQ), told Live Science that the foam "has nothing to do with algae. ... It had something to do with an irrigation cleaning, and it was basically soapy moss."
The canal is connected to the Jordan River, which is connected to the recently algae-covered Utah Lake. The massive algae growth has, at its peak, covered 90 percent of Utah Lake and crept into surrounding tributaries, Spangler said.
Public officials have closed the lake due to concerns about algae, which can release toxins that affect the brain, nervous system and liver function of people exposed to it, Dr. Joseph Miner, executive director of the Utah Department of Health.