East Bay Parks to restore tidal marshes with 77-acre addition of Hayward shoreline

In a move to restore vital marsh habitat and combat sea level rise, the East Bay Regional Park District has acquired 77-acres of the Hayward Regional Shoreline from the Hayward Area Recreation and Park District.

The property transfer this week furthers East Bay Parks’ vision to open the shoreline for public access along the San Francisco Bay Trail and revitalize the tidal marshes that existed there over a century ago, before industrial salt ponds peppered the San Francisco Bay shoreline.

“As sea levels rise, marshes should keep up with it, and so they can rise along with the sea levels, and they can continue providing those benefits decades out into the future,” said Dave Halsing, the executive project manager for the South Bay Salt Pond Restoration Project for the California State Coastal Conservancy. “What’s difficult is having to do it safely.”

The Coastal Conservancy estimates that 85% of the original tidal marshes have been lost to development, both from community expansion and the rise of industrial salt ponds along the bay. The most famous among these salt producers is the Leslie Salt Company, which operated on thousands of acres of coastline across the San Francisco Bay at the peak of production.

Though the most notable of the Leslie Salt Co.’s salt ponds were located along the Peninsula and the South Bay — mountains of salt stood as tall as a seven-story building — East Bay cities like Hayward also saw their tidal marshes turned to salt ponds in the late-1800s and early 20th century.

In 1980, Leslie Sal Co. donated the Hayward Regional Shoreline as part of a regional effort to rehabilitate the Bay Area’s tidal wetlands. East Bay Parks Ward 4 Director Luana España praised the addition of Hayward’s shoreline to the East Bay Parks system as a space for public recreation and wildlife habitation.

“Through this acquisition, the Hayward Regional Shoreline continues to evolve into a prime example of how wildlife habitat restoration, public access and recreation, and resilience can coexist,” España said. “What were once industrial salt ponds are now a home to snowy plovers and a place for the public to enjoy nature along our beautiful restored shoreline.”

The restoration of tidal marshes is also a balancing act, Halsing said. Salt ponds and their levees have a “de facto” benefit of functioning as a break between bay waters and coastal cities, incidentally functioning as flood control.

Opening up salt ponds too quickly without marsh plants taking root, however, can put coastal communities at risk, Halsing said. If salt ponds were totally eliminated, it could also harm birds like slender-necked shorebirds and grebes that rely on them, as other salt lakes across have evaporated or become too high in salt.

“In their normal migration, they would stop in the Great Salt Lake, or at Mono Lake, or at the Salton Sea down in Southern California. And they would spend a couple of weeks there eating the brine shrimp and the brine flies and things that grow in that really salty water,” Halsing said. “There’s all kinds of benefits that marshes provide that these isolated ponds don’t provide, and yet those ponds still do bring some benefit.”

East Bay Parks must play a balancing act, restoring the tidal marshes for indigenous Bay Area species and preserving some salt ponds for migratory species that have come to call the Bay Area home. The agency’s goal moving forward is to replace that incidental protection with intentional preservation that is more adaptable to changing environmental conditions. Research from the Coastal Conservancy suggests that healthy marshes can keep pace with sea-level rise for decades, acting like a sponge that buffers sea water from infiltrating coastal cities — something that static pond levees alone cannot do.

East Bay Parks Ward 3 Director Dennis Waespi emphasized how East Bay Parks environmental stewardship over the sensitive habitat will strengthen the environmental resilience of the agency’s 73 parks, which include 55 miles of shoreline. After generations without the tidal marshes that made the San Francisco Bay’s coastline vital to the reproduction, migration and shelter for so many species, East Bay Parks is preparing to turn back the clock at the Hayward Regional Shoreline.

“This acquisition ensures that restoration efforts and public access move forward together, benefiting the community and local habitat for generations to come,” Waespi said.