Greening Stormwater

Greening Stormwater

image of bioretention site

When rain runs off into the San Francisco Estuary from streets, parking lots, and other hard surfaces, it can carry a toxic soup of contaminants—oil, grease, and myriad other chemicals that may start off as pollutants in the air but end up on the ground where they can they then be washed into water bodies in storms. For the past three decades, Bay Area scientists have tracked and analyzed these contaminants to determine exactly what they are and how they affect water quality. Water quality agencies, meanwhile, have developed increasingly stringent regulations—such as TMDLs, or Total Maximum Daily Loads and other mechanisms—to try to control them.

In more recent years, the practice of Green Stormwater Treatment—the use of soil and plants to slow, spread, sink—and filter—pollutants from roads and other surfaces before they run off into the Estuary started to come into its own. The Bay Area was slow to adopt these practices. In the early 2000s, Estuary News reported on neighborhood activists taking jackhammers to concrete in San Francisco’s flood-prone Mission District and urging the city to pass ordinances to stop more paving of permeable surfaces. But the regulatory community wasn’t convinced, and didn’t have a coherent strategy for requiring cities to dig up pavement and asphalt to benefit water quality. Big-picture thinkers shared innovations from around the world; Estuary News wrote about innovations in the Pacific Northwest, and slowly things began to change. After vehicle registration fees helped fund pilot projects in San Mateo County in 2009, followed by similar projects sponsored by the Estuary Partnership in the East Bay beginning in 2011, and finally, by 2019, a regulatory requirement that cities comply with their stormwater permits by incorporating green infrastructure, things began to change.

Editor’s Picks

  • West Coast Salmonids All Tired Out?
    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 […]

  • Match Points in Stormwater Soup
    Match Points in Stormwater Soup

    Effluent from wastewater treatment plants is often seen as the primary source of emerging contaminants in San Francisco Bay. But a report published in July by the Regional Monitoring Program challenges that assumption by highlighting the importance of urban stormwater runoff as another major source.

  • Next Day Delivery: PCBs, Plastics, and Mercury All in One Package
    Next Day Delivery: PCBs, Plastics, and Mercury All in One Package

    The slow, downstream chemical migration of legacy contaminants like mercury and PCBs into the Bay is something that Lester McKee and his colleagues at the San Francisco Estuary Institute hope to cut short. “The sooner we can stop the inputs of these contaminants,” says SFEI’s Alicia Gilbreath, “the sooner the Bay can have a chance to recover.”

  • Needed Now: A Big Blue-Green Push
    Needed Now: A Big Blue-Green Push

    From rain gardens to green streets to permeable parking lots and pebble dunes, landscape architects and resource managers are working to soften up shorelines and sidewalks, all to sponge up and filter stormwater runoff before it reaches the Estuary. This article details projects in the South Bay Salt Pond Project’s Eden Landing, Hayward’s Turner Court, and the Delta’s Elk Grove, and along the East Bay’s San Pablo Avenue and San Jose’s Chynoweth Avenue.


Further Selections

  • Ballpark Battlegrounds
    Ballpark Battlegrounds

    McKelvey Park’s curious design reveals its double use: a baseball field that is also a flood detention basin designed to protect Mountain View from Permanente Creek’s next major 50- to 100-year flood.

  • Microtrash Tiresome for Watersheds
    Microtrash Tiresome for Watersheds

    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…

  • Putting Roads on a Green Diet
    Putting Roads on a Green Diet

    While trying to add bike lanes and bioretention facilities to San Pablo’s Rumrill Boulevard in the East Bay, Amanda Booth learned a central lesson. Look underground first. Booth is one of many managers around the region trying to build green stormwater infrastructure to prevent polluted runoff from draining into the Bay.

  • Clock Ticking for Cities to Commit to Greening
    Clock Ticking for Cities to Commit to Greening

    Managing stormwater is a physics problem, and not a very glamorous one. In decades past, the main objective of managing stormwater was figuring out how fast it could be directed through the Bay Area’s built landscape via storm drains, culverts, and channels, and into the Bay. In decades future, however, the object will be to […]

  • The Second Signal: Guadalupe River Flood Monitoring
    The Second Signal: Guadalupe River Flood Monitoring

    It was past midnight when Lester McKee pulled the plug. He’d been watching the weather for days on screen, looking for the perfect storm of conditions he needed to send his team out to sample the Guadalupe River in Santa Clara County. He knew there’d been enough rain already to saturate the soil and surpass […]

  • Urban Jungle Inspires Unique Regulatory Tack
    Urban Jungle Inspires Unique Regulatory Tack

    Out of all the social and environmental costs of homelessness, the trash that blows from encampments into waterways may help spur a solution to this problem in the Bay Area. Under a new resolution by the SF Bay Regional Water Quality Control Board, trash from homeless encampments now falls under the stormwater permit that requires Bay Area cities and counties to get storm drains virtually trash-free by 2022.

  • Waiting for the Big One
    Waiting for the Big One

    If and when El Niño decides to dump a big storm on the Bay Area — even at 2:00 am on a Saturday night — SFEI’s Lester McKee and Alicia Gilbreath and their team are ready to pull on their parkas and dash out to take water samples.“With plenty of data for normal years, it was important to get data from a more extreme year,” says Phil Trowbridge…

  • Beyond the Bag Ban
    Beyond the Bag Ban

    The other day I found myself turning out the closets for one last plastic bag. But a year into San Francisco’s bag ban, there just aren’t that many plastic shopping bags around our house anymore. All told, 60 percent of municipalities in the four most urbanized Bay Area counties have banned them. It’s all part of a substantial endeavor by regional regulators and 76 local municipalities to stop litter, PCBs and mercury from getting into our creeks and Bay via stormwater runoff.

  • Editor’s Pick Stormwater Stories 1993-2013
    Editor’s Pick Stormwater Stories 1993-2013

    Walk back through time with this selection of early stories from Estuary’s first two decades of publication. Stories explore fledgling efforts to monitor, filter and curb stormwater pollution, ranging from rain gardens to vehicle registration fees.

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American Avocet on managed, former salt ponds in the South Bay. Photo: Roopak Bhatt, USGS

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