In the absence of a government program to contend with harmful algae blooms (HABs) in the Delta, a loose coalition of academics and environmental and community groups has been studying their spread and potential health impacts both from ground level and from the air.

In the absence of a government program to contend with harmful algae blooms (HABs) in the Delta, a loose coalition of academics and environmental and community groups has been studying their spread and potential health impacts both from ground level and from the air.

San Francisco Baykeeper has been sending up drones to monitor eight sites between Discovery Bay and downtown Stockton, as well as photo-documenting the spread and intensity of HABs from airplanes flown by Lighthawk Conservation Flying. At the same time, volunteers with Restore the Delta have been conducting water quality testing for HABs and the toxins they produce. “The airplane and drones together allow us to get a really broad geographic understanding of where these neon green HABs are occurring, says...
Read More

Groundwater pumped from subsided islands back into Delta channels through 200 or more active outfalls can be laden with excess nitrogen transported from island soils, report the authors of a new study.

The Sacramento-San Joaquin Delta contains more than 50 peat islands. Most have subsided—some as much as three meters — as a result of drainage for farming, and must maintain artificial water tables below the land surface via managed pumping. According to researchers from the University of California at Santa Cruz and the US Geological Survey, these pump stations are an underappreciated source of nutrients in nearby waters, with potentially significant implications for habitat and water quality.   To get a...
Read More

Bagman for Bay Mussels

Martin Trinh practically bounces along the dock at the Coyote Point Yacht Club on a breezy, sunny spring morning. He’s carrying a case full of instruments and scopes out an open slip at the end of the pier. Soon he’s lowering a probe into the water, alongside kelp clinging to the underside of the dock. Another trip back to his Prius, still sporting South Carolina license plates, and he’s got a white plastic dish pan and a scrub brush. He...
Read More

West Coast Salmonids All Tired Out?

West Coast salmon and steelhead populations have declined steeply in the past century – a plight that biologists have primarily blamed on habitat loss. Dams, for instance, block adult fish’s access to historic spawning grounds, and juvenile survival is impacted by streamside development and water diversions. Now, it turns out, microplastic pollution may be a much bigger factor than anyone knew just several years ago. In 2019, scientists with the San Francisco Estuary Institute and the Los Angeles-based nonprofit 5...
Read More

When it comes to managing Delta salinity, a new research paper suggests we treat public policy like a science experiment.

As anthropogenic factors like salt accumulation through irrigation and freshwater storage combine with drought and sea-level rise, the Delta is headed for a saltier future. The June 2021 paper, published in San Francisco Estuary and Watershed Science, integrates biological and physical sciences to draw a comprehensive picture of Delta salinity and changing freshwater inflow. Changing salinity patterns could have a profound impact on the region’s ecology, affecting how and when fish like the Delta smelt or Coho salmon spawn, and which aquatic plants...
Read More

Bay Fish Still Not Good Eating

After decades of efforts to clean up San Francisco Bay, its fish still carry a toxic load that makes them unfit for human consumption. A new Regional Monitoring Program (RMP) report on its 2019 sport fish survey contains some positive news: an overall decline in polybrominated diphenyl ethers (PBDE), hopeful trends in polychlorinated biphenyls (PCBs) and dioxin, and continued low selenium levels. But no downward trend was found for mercury. Then there are per- and polyfluoroalkyl substances (PFAS), which the...
Read More
sunset delta climate map

MEGA-PEARLS Part 4-Climate, Bay-Delta Science Conference, April 2021

A Stream of Science Takeaways. ESTUARY News sent reporters to the biennial Bay-Delta Science Conference in September. This special edition of Pearls shares more than 20 takeaways.
Read More
pesticide resistance delta map

MEGA-PEARLS Part 3-HABs & More, Bay-Delta Science Conference, April 2021

A Stream of Science Takeaways. ESTUARY News sent reporters to the biennial Bay-Delta Science Conference in September. This special edition of Pearls shares more than 20 takeaways.
Read More
photo of salmon injection USFWS

MEGA-PEARLS Part 2-Fish-Birds, Bay-Delta Science Conference, April 2021

A Stream of Science Takeaways. ESTUARY News sent reporters to the biennial Bay-Delta Science Conference in September. This special edition of Pearls shares more than 20 takeaways.
Read More
Above: Lewis holding white sturgeon in Delta. Photo: Jim Ervin

MEGA-PEARLS-Part 1-Diversity, April 2021

A Stream of Science Takeaways. ESTUARY News sent reporters to the biennial Bay-Delta Science Conference in September. This special edition of Pearls shares more than 20 takeaways.
Read More

Bay Oil Spills: Never Again, and Again

Oil spills in San Francisco Bay are frequent news, but for those old enough to remember there is only one Great Oil Spill, the disaster of January 18, 1971. In a predawn darkness thickened by heavy fog, two small Chevron tankers were maneuvering through the strait. At San Francisco’s Pier 45, Coast Guard technicians were just then testing a novel radar system. They watched helplessly as two blips threatened to fuse into one. Frantic calls to the captains failed to...
Read More

The increasing flow of microplastics entering San Francisco Bay from trash, fleece clothing, car tires, and myriad other sources is likely being trapped by a surprising filter: native eelgrass (Zostera marina).

Miniscule polymer pieces the size of a sesame seed or tinier, microplastics pose a growing pollution threat to marine environments worldwide. To understand how microplastics accumulate in nearshore, urbanized environments, researchers quantified the prevalence of microplastics in and around the Zostera marina meadows of Deerness Sound, in the Orkney Islands of Scotland. Mark Hartl and colleagues at Heriot-Watt University found that microplastic flakes, fibers, and fragments were twice as concentrated in the water above eelgrass meadows as in adjacent control...
Read More

Covid Clues from Wastewater

As COVID-19 continues its unrelenting rampage, wastewater plant managers and university researchers are ramping up their efforts to monitor wastewater for SARS-CoV-2, the virus that causes the disease. Their goal is to give public health departments a powerful tool: an early warning system for new outbreaks in communities. In Yosemite Valley, for instance, wastewater testing revealed the presence of the virus in the community before swab testing of individuals showed a problem. “There’s a time delay before cases appear in...
Read More

A Fragile Fleet

The naming of boats and ships is a serious matter. Each larger vessel’s name starts with a code that tells what it carries, what propels it, or what purpose it serves. If it were your hobby to keep tabs on traffic on San Francisco Bay, you’d see a lot of big UCCs (container ships) and TCHs and TCRs (tankers). You’d see ferries emblazoned with MV, standing for “motor vessel.” Before COVID-19, you would have spotted the occasional SS, standing for...
Read More

The Delta’s Blooming Problem

Bright-green blotches of algae have been popping up all over the Delta since early summer, from Discovery Bay to the Stockton waterfront, befouling the air and poisoning the water with toxins that can sicken or even kill humans and animals. Veteran Delta watchers believe that this year’s harmful algal blooms may be the worst ever, and worry that some features of Governor Gavin Newsom’s recently released Water Resilience Portfolio for California will aggravate the problem. “We don’t have enough data...
Read More

Match Points in Stormwater Soup

Scientists studying environmental pollutants tend to divide them into two distinct groups. One includes “legacy” contaminants that drew attention during the early stages of the environmental movement, like mercury, PCBs, and some pesticides. The other is a much larger class of “emerging” contaminants whose production or monitoring began more recently and about whom less is known; think pharmaceuticals, plastic additives, and flame retardants. Effluent from wastewater treatment plants is often seen as the primary source of emerging contaminants in San...
Read More

A team of scientists is close to chasing down every last thing that happens to nitrogen in wastewater as it passes through the soils and plants of a horizontal levee.

Not only is 97% of the nitrogen removed, but also trace pharmaceuticals. “You just have to focus on where the water is going,” says environmental engineer Aidan Cecchetti, referring to the UC Berkeley-Stanford-ReNUWIt team’s experimentation with three components of flow through the levee system—under the surface, over the surface, or into the air (through evapotranspiration). “In the wastewater pumped to the subsurface, you see full removal of every contaminant except phosphorous.” What’s most astonishing is how much of the work...
Read More

Microtrash Tiresome for Watersheds

By Jacoba Charles As many as 30 particles of microplastic smaller than five millimeters in diameter are discharged with every liter of stormwater, according to a report published by the San Francisco Estuary Institute and 5Gyres last October. “A big proportion of what we saw were black rubbery fragments,” says SFEI’s Diana Lin, a lead author of the report. Apart from these likely biproducts of tire wear and tear, hair-like threads of fiber were the other main type of microplastics...
Read More

Kinky Fish Spines Linked to Selenium

By Joe Eaton Scientists with the U.S. Geological Survey and the National Oceanic and Atmospheric Administration are using new tools to track selenium, with the Sacramento splittail, a California-endemic fish, as an indicator species. Robin Stewart, lead author of a new paper on splittail and selenium, is one of the region’s most seasoned current experts on bioaccumulation of metals in estuarine species. In some sampled splittail, selenium levels exceeded the proposed EPA protective criteria for fish ovaries. Liver levels, not...
Read More

Toxins Flock to Beads in a Scientific Tea Bag

By Ashleigh Papp When a New Zealand scientist shared a novel method to test water quality in the early 2000s that didn’t involve harvesting shellfish, UC Santa Cruz’ Raphael Kudela and his team of researchers quickly adopted the idea. After some fine-tuning, they named their new technique Solid Phase Adsorption Toxin Testing (SPATT, for short). The technique takes advantage of custom-built plastic, or resin, beads that are designed to absorb specific things. “It looks a lot like a tea bag,”...
Read More
1 2 3 4