By Science Director Eric Lynch
SFBBO’s Habitats Team is wrapping up its initial planting of the roughly 2 miles of new levee just constructed at Don Edwards NWR in Alviso. The new levee, which is actually an old levee that was raised about 9 vertical feet, comprises Reaches 1-3 of the South San Francisco Bay Shoreline Project’s Flood Risk Management levee. This levee is designed to protect low-lying South Bay shoreline communities like Alviso from the increasing flood risk brought on by sea level rise. Once additional reaches of the levee are complete, it will also help facilitate the restoration of thousands of acres of former salt ponds to tidal marsh.
With generous funding from the State Coastal Conservancy, and help from wonderful partners like the U.S. Fish & Wildlife Service, Valley Water, and H. T. Harvey, SFBBO spent the last 3 years rebuilding a native plant nursery at Don Edwards NWR in Fremont, and then grew over 35,000 plants for the new levee. Most of these plants were installed at the “toe” of the levee to help prevent erosion from wind waves and facilitate the rapid establishment of native plant communities that will benefit local wildlife.
Salt-tolerant stands of pickleweed, salt grass, alkali heath, marsh gumplant, and salty susan will provide habitat for a variety of species at the toe of the levee, and large patches of salt grass placed along the mid-slopes of the levee will provide low, invasion-resistant grassland for foraging birds. A few tidal and tidal-adjacent areas were planted with a greater diversity of plants often found in upland areas adjacent to marshes. The hard-working members of the San Jose Conservation Corps helped the hard-working members of the Habitats team complete the planting over a period of about 2 months. The rest of the levee was treated with a mix of native seeds and goldfields, tidy tips, red maids, and fiddlenecks are currently blooming in great abundance.
The levee is currently open to visitors after 3 long years of closure for construction work. Reach 1 can be accessed from Alviso Marina County Park, and Reaches 2-3 can be accessed from the Don Edwards Alviso Environmental Education Center. Visitors can connect the two levee sections by taking a long detour north to cross the Union Pacific Rail Road tracks which bisect the levee. SFFBO’s work is not done out there – we have 3 years of managing vegetation, surveying results, replanting, and reseeding the levee to help usher it through its early years. We hope you’ll come out and visit the levee to enjoy some spring flowers, birding, and wide open views. If you see our staff working out there, please stop and say hello!
