Every two years, scientists, legislators, and community members meet to discuss the health and future of our beloved San Francisco Bay.
At this year’s State of the Estuary Conference, which is taking place this week at the Oakland Scottish Rite Center across from Lake Merritt, harmful algae blooms, wetland restoration, and emerging contaminants are a few of the items up for conversation.
According to event organizers, the conference will serve as a hub for in-depth, timely conversations about the concerns, interests, and hopes of those “who are impacted by and working to improve, conserve, and monitor the health of the estuary.”
The event is organized by the San Francisco Estuary Partnership. It’s part of the National Estuary Program, which was created by the U.S. Environmental Protection Agency in 1987 to protect and restore environmentally significant estuaries across the country. The San Francisco Estuary is one of 28 estuaries covered by the program.
An estuary is a place where freshwater and saltwater meet. The San Francisco Estuary—what we residents commonly refer to as the San Francisco Bay—is the largest estuary in California and extends across nearly 40% of the state.
Estuaries are unique habitats. According to the EPA, they are some of the most productive ecosystems on our planet, “creating more organic matter each year than comparably-sized areas of forest, grassland or agricultural land.” Many marine and avian species rely on estuaries for their survival.
The San Francisco Bay-Delta is also a vital source of freshwater, agricultural area, and recreation for millions of California residents.
Understanding harmful algal blooms
One of the key topics discussed at Tuesday’s conference was the study and understanding of harmful algal blooms, often referred to as HABs within the scientific community.
A harmful algal bloom is a sudden growth of algae that negatively affects the surrounding ecosystem by releasing toxins, lowering the amount of oxygen in the water, or causing mechanical damage. These blooms can happen in both freshwater and saltwater, and they’ve become an increasing concern for those working on water bodies across the Bay.
In August 2022, the San Francisco Bay saw a massive bloom of the algae Heterosigma Akashiwo, a type of algae that is often linked to harmful algal bloom events. The event led to a devastating fish kill; the California Ocean Protection Council estimated that as many as 10,000 fish died during the event. The bloom disappeared just as quickly as it arrived, leaving scientists scrambling to make sense of the event.
“HABs are notoriously hard to understand,” said David Senn, one of the conference panelists for a discussion focused on harmful algal blooms and the program director for the San Francisco Estuary Institute’s Clean Water Program.
Senn and other Bay Area researchers have been investigating the factors behind the August 2022 bloom, hoping to understand the possibility of future blooms and build a framework to improve monitoring and early detection.
Due to the complicated nature and scope of blooms, there has historically been a lack of coordination between entities responsible for monitoring harmful blooms. The San Francisco Estuary currently has no long-term, coordinated program to monitor harmful algal blooms.
A variety of factors can contribute to the likelihood of a harmful algal bloom occurring. Algal blooms like nutrient-rich waters, which our bay and the nearby Sacramento-San Joaquin Delta are full of. They also like warm temperatures, sunlight, and decreased water mixing. As changes in the climate cause increases in temperatures, they could become more frequent.
Since 2022, harmful algal bloom events across the Bay Area have appeared to go down as more rainwater has increased flows across freshwater bodies. However, “HABS are likely to worsen if—more likely when—drought conditions return,” said panelist Spencer Fern, delta science program manager for Restore the Delta, in a pre-recorded talk for the conference.
Fern’s discussion focused on some of the communities facing the most significant effects of harmful bloom events: frontline, disadvantaged communities—people who experience the first and most significant impacts of climate change.
Drinking, swimming in, or otherwise coming into contact with waters that are experiencing a harmful algal bloom can have a variety of negative effects on the body, like rashes, respiratory issues and gastrointestinal problems. Pets can face life-threatening complications if they drink a significant amount of bloom-laden water.
People who live, hang out, and work around these waters face the highest risks and are also least likely to receive good, timely information that a harmful bloom is happening. Residents of indigenous communities who rely on these waters for cultural events, agricultural use, and subsistence fishing can face some of the most significant impacts of bloom events.
Researchers, non-profit groups, and tribal organizations around the state are working to improve adequate water testing systems and information-sharing systems to address this issue.
“Informing communities helps strengthen communities,” said Fern.
