Tiscornia Marsh Restoration and Sea Level Rise Adaptation

Marin Audubon Society
Planning/Design, Community Engagement, Construction
Ducks on Tiscornia Marsh
Grant Amount:
  • $968,916 June 2019 board authorization for planning
  • $70,847 Executive Officer Augmentation for planning
  • $3,082,000 April 2022 board authorization for initial construction
  • $386,000 December 2022 board augmentation for initial construction



Tiscornia Marsh, City of San Rafael, Marin County, North Region

Project Phases Funded by this Grant:

Planning/Design, Community Engagement, Construction

Measure AA Program Category:

Safe, Clean Water and Pollution Prevention Program; Vital Fish, Bird and Wildlife Habitat Program; Integrated Flood Protection Program; Shoreline Public Access Program


2023 UPDATE: Marin Audubon Society is currently working on permitting and final design under a grant from the Ocean Protection Council. In FY 23/24, they will use Restoration Authority funds to finish final design, permitting, and begin construction. 

The initial grant for $968,916 to Marin Audubon Society in June 2019 funded initial planning; this was augmented by $100,000 by the Authority's Executive Officer. In April 2022, the Governing Board authorized a further $3,082,000 to prepare permit applications, develop final designs, continue engaging community members, and begin construction for the restoration of Tiscornia Marsh. A further augmentation in December 2022 of $386,000 will help advance the project and cover revised construction costs. 


This project will prepare technical studies, refine designs, and conduct CEQA review and public outreach for marsh restoration and sea level rise adaptation actions at Tiscornia Marsh, which are expected to expand marsh habitat, increase flood protection, and provide public access at the mouth of the San Rafael Canal in Marin County.

The planning project is expected to evaluate feasibility and environmental effects of various potential improvements including:

  • Expanding the existing marsh (up to 10 acres) through placement of beneficially reused dredged material;
  • Restoring the six-acre diked marsh to tidal action;
  • Constructing a new setback levee on the City’s property;
  • Improving an additional 2,000 feet of the existing levee by raising it and incorporating an ecotone slope;
  • Creating a coarse beach along the eastern marsh boundary to protect against marsh erosion and trap sediments;
  • Creating a living seawall/rock jetty along the north marsh boundary in response to boat wake in the San Rafael Canal;
  • Constructing a segment of the Bay Trail on the new setback levee; and
  • Providing additional recreation amenities, which may include interpretive signage, benches, picnic tables, and a bicycle rack