Will this winter’s megastorms end the Bay Area’s toxic algae problem?
In recent years, thick layers of cyanobacteria—commonly known as blue-green algae—have closed popular local swimming spots Lake Anza and Lake Temescal for weeks at a time. Last summer, a toxic algae bloom in the San Francisco Bay killed thousands of fish. Although algae is always present in some quantity in lakes and the bay, higher temperatures, stagnant water, and excessive nutrient levels can cause the algae to multiply. If the particular species has toxins in it, such as blue-green algae or the Heterosigma akashiwo species that bloomed in the bay last summer, the water can become unsafe for humans and animals. Algae blooms and cyanobacteria have become state and nationwide problems. In the Bay Area, water managers were beginning to wonder if the extreme drought conditions of recent years had pushed the problem into a dangerous new phase in local waters.