Combatting Rising Tides at Bothin Marsh

Photo from SF Bay Restoration Authority | post by Larry Clinton

Just north of the Richardson Bay Bridge, the Bothin Marsh Open Space Preserve and a section of the multi–use path are experiencing frequent and severe flooding that impacts the shoreline, plants, wildlife, and use of the pathway.

The Preserve is Marin County Parks’ most visited park unit and the most vulnerable to sea level rise. The Preserve’s 67 acres of tidal wetlands are particularly vulnerable to sea level rise due to the relatively low ambient suspended sediment concentrations in this part of Richardson Bay. This limits the wetlands’ ability to grow vertically to keep up with sea level rise, which is typically achieved in regions like these by capturing sediment. Although the complex is relatively small compared to other marsh complexes in San Francisco Bay, it is the largest remaining tidal marsh habitat in Richardson Bay—it supports higher than average biodiversity and provides critical habitat for wildlife in the region.

The Evolving Shorelines Project is exploring plans to protect, restore, and enhance the Preserve and elevate and realign a one–mile segment of the Bay Trail out of its existing flood–prone location. The Golden Gate National Parks Conservancy and Marin County Parks are co-managing this effort to adapt the tidal marsh complex to sea level rise and to ensure continued public access to the shoreline through nature–based strategies.

You can stay informed about the work scientists, researchers, engineers, and designers are doing to address the challenge of sea level rise at Bothin Marsh by visiting the Evolving Shorelines online storymap. It’s a fast and engaging way to learn about the history of the marsh, how rising tides affect recreation and wildlife habitat and ongoing efforts to find solutions.