Reddish-brown algae harmful to fish and other marine life has appeared along the shores of Emeryville, Berkeley and Albany, environmental group San Francisco Baykeeper confirmed Monday.
Last year, a harmful algae bloom of the same kind caused a red tide spreading across San Francisco Bay, resulting in an unprecedented fish kill event.
Baykeeper scientists say that the algae bloom is likely fueled by elevated levels of nitrogen and phosphorus - substances released into the sea by the region's 37 wastewater treatment plants.
"It's alarming to see an algae outbreak of this size in the Bay for the second year in a row," said Baykeeper science director Jon Rosenfield. "While it's too early to tell how this harmful algae bloom will proceed, there's not much that we can do to stop it once it has started. Prevention is the only cure."
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Baykeeper urges the San Francisco Bay Regional Water Quality Control Board to upgrade permits for Bay Area wastewater treatment facilities to dramatically reduce nutrient loads discharged into the bay.
The organization also calls on the public to report any water that looks or smells suspicious to its pollution hotline.
"The organism that likely forms this bloom is not known to pose a risk to humans," said Rosenfield. "Regardless, we advise caution when entering any water that is discolored."
