San Rafael, CA – In a forward-thinking effort to provide critical habitat and ensure that Marin’s marshlands and critical infrastructure can withstand sea-level rise, Marin County Parks is using a $550,000 state grant to restore 180 acres of diked wetlands in San Rafael to natural marsh.
Parts of McInnis Park Golf Course routinely flood when a winter storm combines with a king tide. Improved wetlands should fix the problem and restore wetlands in the area.
Three months after the California Department of Fish and Wildlife approved the grant to prepare project designs and an environmental review, the Marin County Board of Supervisors will receive a feasibility study for the
McInnis Marsh Restoration Project during its April 11 meeting.
Parks estimates the project will cost $5 million to $10 million. It plans to use seed funding from taxpayer-supported Measure A to leverage funding from other sources including Measure AA, a Bay Area parcel tax that could raise up to $500 million over 20 years to fund projects that will protect and restore the bay.
The McInnis Marsh project includes replacing a non-engineered levee system, which dates to the early 1900s, with a new environmentally friendly levee closer to the County-owned McInnis Golf Course and the adjacent Las Gallinas Valley Sanitary District water treatment plant, and allowing the bay to reclaim the historic tidelands.
James Raives, Senior Open Space Planner for Parks, said the project will protect a popular regional park while improving habitat and providing area to accommodate sea-level rise.
“This project not only allows for the migration of critical marsh habitat as the climate changes and sea level rises, it also provides protection for infrastructure,” Raives said. “If we do nothing, we could lose endangered species habitat, recreational facilities, and the treatment plant.”
The project dates to September 2012 when Parks, the Marin County Flood Control and Water Conservation District, and the Las Gallinas Valley Sanitary District established a partnership to study restoration of the wetlands. The California State Coastal Conservancy funded the feasibility study with a $90,000 grant.
The project would entail intentional breaches of Gallinas and Miller creeks to allow water flow into the marsh at low tide. The new gentle sloping levee design would not only protect the park and the water treatment plant but combine ecological function with more modern and effective flood control. With a design that incorporates vegetation to mimic the natural shoreline, the levee would improve habitats for threatened and endangered species such as Ridgway’s rail, the California black rail, the saltmarsh harvest mouse and the steelhead trout.
What does this mean for hikers? Parks will construct a trail on top of the new levee that will be more accessible for hikers of all ages and physical abilities. The new trail will connect to nature trails on sanitary district land and would be part of the San Francisco Bay Trail, a planned 500-mile walking and cycling path that runs through all nine Bay Area counties, 47 cities, and across seven toll bridges.
“Climate change and sea level rise is one of the greatest challenges of our generation,” said Parks Director Max Korten. “We need to plan ahead to make sure that the things we value, like parks, marshes, wildlife and important infrastructure are able to survive these changes.”
Learn more about local efforts to address sea-level rise at www.marinSLR.org.