Marin County Flood Control Receives Grant for Proposed Deer Island Restoration

The San Francisco Bay Restoration Authority (SFBRA) Measure AA has awarded a $520,000 grant to the Marin County Flood Control and Water Conservation District (MCFCWCD) for the design and environmental compliance phase of the proposed Deer Island Basin Tidal Wetlands Restoration Project (DIBTWRP) located in the Bay Area town of Novato. Measure AA funds are available to all nine Bay Area counties in the form of an annual, competitive grant application process. The SFBRA is a regional agency charged with raising and allocating local resources for the restoration, enhancement, protection, and enjoyment of wetlands and wildlife habitat in San Francisco Bay and its shoreline, and associated flood management and public access infrastructure.

With the new grant funds secured the restoration project has begun its design phase. The project seeks to restore 50 to 110 acres to natural wetlands around Deer Island, located along Novato Creek. An additional 35 to 45 acres could also potentially be restored by removing levees from Ducks Bill and Herons Beak ponds, which are adjacent to Novato Creek. The design phase is expected to be completed by early 2020.

Deer Island sits at a critical junction of freshwater and saltwater where Novato Creek enters San Pablo Bay. The location is one of only a handful in the Bay Area that still has the potential to restore tidal marsh within this freshwater/saltwater mixing zone.

A wide variety of threatened and endangered species inhabit this complex marsh ecosystem. These zones are critical because they provide a unique habitat for wildlife including the vital nesting and breeding grounds for these species. Many of these habitats have been lost over the decades to land developments, ranching and agricultural areas.

If the proposed project changes to Deer Island were to be made, it is expected they would increase the tidal area and thereby improve floodplain functionality. The potential improvements would benefit the Novato watershed area, known as Flood Control Zone 1 (FCZ1), not only ecologically ecological but also for flood mitigation measures and sea-level rise adaptation.

“Restoring the area to its natural state is a significant undertaking and it is not going to happen overnight,” said Roger Leventhal, Marin County Flood Control District’s senior civil engineer. “It may take years for the restored areas to return to a more natural tidal system, but we’ll experience those benefits and it’ll be a great asset for future generations.”

The proposed plan includes constructing horizontal “ecotone” levees immediately adjacent to the tidal wetlands. This area would function as a transition zone for sea-level rise conditions, fundamentally improving the resiliency of the marsh wetlands. The expansion of wetland area would naturally improve flood mitigation for FCZ1 by allowing for the dispersion of floodwaters during storm events and king tides.

The logistics for the Deer Island project includes fist determining a cost-effective design and then passing the California Environmental Quality Act (CEQA) process. After gaining CEQA’s approval the project would seek permits from the various regulatory agencies to begin the work.

However, the Deer Island project would need to wait until additional funding could be identified before the actual restoration could begin. Whereas the project could apply and be eligible for an additional $110,00 in Measure AA grant funding for the permitting phase and there is no guarantee that funds will be awarded to FCZ1 in any given year, nor to any of the other flood control zones under the District’s supervision. Once funds are identified and secured for the permits, still other funds would need to be secured for the actual construction; currently there are no FCZ1 funds available for construction.

Estimates for the Deer Island restoration project costs to range from $8 to $12 million though many variables could affect the project and its final cost. However, it is unlikely that the Marin County district would be awarded the entire funding needed for the project from Measure AA and, therefore, the district will seek additional grant funding sources to offset the costs of the Deer Island Restoration project.