Last weekend, over fifty volunteers gathered at the Oro Loma Sanitary District treatment plant in San Lorenzo to kick off an ambitious burst of planting activity in a soon-to-be restored wetland. Participants included a contingent of local college students, parents and their teenage children, and a few veteran helpers. Equipped with trowels and picks, attendees placed 3,200 plants into a plot of soil next to the sewage treatment plant.
Though the plants were all put in the ground in about an hour, an enormous amount of planning went into how they were selected and configured. Save The Bay’s habitat restoration team has been working for over a year to cultivate several palettes of wetland plants that will be planted next to each other. They will become part of a scientific experiment exploring what combination of plants and soils can best filter excess nutrients from the treated wastewater that will be pumped in from the adjacent sewage plant.
A new kind of levee
This is exciting, because if this pilot project is successful, it could be replicated elsewhere as a means of naturally improving water quality, providing needed habitat for sensitive species, and forming a more durable barrier to flooding from storms and sea level rise. This horizontal levee is an alternative to steep earthen or rock walls that traditionally separate the Bay from vulnerable land — this marsh will gently slope upwards, enabling it to better adapt to rising tides.
After the planting was completed, participants joined the public open house being hosted by the Oro Loma Sanitary District. Horizontal levee project scientists and treatment plant workers were on hand to give tours, and Save The Bay staff answered questions about their work. Also present were local elected officials, representatives of the Castro Valley Sanitary District, which co-owns the treatment plant, as well as UC Berkeley researchers who will analyze the filtering capacity of the wetland once it is operational.
Over the next two months, our goal is to put in 70,000 plants at this site. If this project sounds interesting and you’d like to pitch in, you’re in luck! Save The Bay will be hosting 3 more volunteer planting workdays at Oro Loma, on November 21, December 5, and December 12. Click here to volunteer!