By Julie Horner
The City of Santa Cruz Public Works has announced plans to remove vegetation from the 2.2-mile urban stretch of the San Lorenzo River — from the Highway 1 bridge to the mouth of the river, where it enters Monterey Bay. The river is bordered on either side by concrete levees intended to prevent flooding into the residential neighborhoods and downtown areas. Linda Skeff, director of the Valley Women’s Club San Lorenzo Valley Native Habitat Restoration Program notes that “the riverbanks of these levees have accumulated sand and soil to sustain native vegetation, which provides food, shelter, and nesting areas for local and migratory bird populations as well as shade and sustenance for steelhead trout and Coho salmon.”
Restoring a sustainable estuary ecosystem along the San Lorenzo River levee has been an ongoing project sponsored by the VWC. Santa Cruz environmentalist Jane Mio and a network of volunteers have been revegetating the river banks within the levee with native plants to attract wildlife and expand the riparian corridor. Because of the work carried out by The San Lorenzo River Estuary Project, the levee is now home to lizards, insects, aquatic animals, and resident and migratory birds. According to Skeff and her team, “This stretch of the river is recognized as a valuable resource with diverse microsystems that are essential to the integrity of the native habitat in the lower San Lorenzo River and estuary and integral to the overall health of the San Lorenzo Valley Watershed.” Read more about the restoration efforts: slvhabitatrestoration.org.
In July 2020, the Army Corps of Engineers, which owns the levee, transferred responsibility for levee maintenance to the City, triggering a July 2023 FEMA accreditation deadline. The San Lorenzo River FEMA Levee Accreditation Vegetation Management and Burrowing Rodent Mitigation Projects (c402102) were introduced to the City Council in December of 2022. The project specifies “vegetation management and burrowing rodent mitigation activities to bring the City’s levees into maintenance compliance for the City’s FEMA levee accreditation effort.” The work to be carried out: “Complete vegetation management activities on the San Lorenzo River levees including but not limited to mowing, grubbing, trimming, and liming.” The expected result: “To ensure visibility of the Levee slope.” Vegetation removal is limited to the following criteria:
1. Water Side: Upper 20 feet of the water side slope as measured from the edge of paved levee path or to top of rip rap armoring whichever is less
2. Land Side: From edge of paved levee path to levee toe
Further, “Any areas disturbed by vegetation management shall be revegetated with a native plants seed mix that is ‘mow-able’ and provides the best possible biodiversity and habitat value.” The work is to be carried out by hand, and the use of herbicide is allowed, if necessary, according to contract details.
The City notified the public in December that the vegetation along the levee would be removed due to concerns about levee effectiveness during high water events, even though a 1982 finding by UCSC Professor Gary Griggs indicated that the presence of vegetation did not affect flow. Those findings have not been added to FEMA protocols.
What you can do
Learn about the unique ecosystems in your neighborhood and how to help them thrive, and let your representatives know you want them to support our local environment:
City Council: email@example.com
Mayor Fred Keeley: firstname.lastname@example.org
Supervisor Justin Cummings: email@example.com
Senator John Laird: Senator.Laird@senate.ca.gov
Support local organizations that sustain native habitat restoration in the county. Contact Jane Mio, Program Director, San Lorenzo River Estuary Project, SLV Native Habitat Restoration Program, at (831) 429-1461.
Julie Horner writes about art, music, and culture in the Santa Cruz Mountains. Reach out to Julie at firstname.lastname@example.org.
Featured photo: The San Lorenzo River at the Soquel Avenue Bridge. Photo contributed