Giacomini Wetlands Reopened to the Tides
Contact: John Dell’Osso, 415-464-5135
Contact: Lorraine Parsons, 415-464-5193
On October 26, the Giacomini Wetlands in the Golden Gate National Recreation Area will fill with the high tide for the first time in over 60 years, marking an important milestone in recovering the health of the Tomales Bay watershed.
Two-thirds of Tomales Bay’s freshwater inflow comes from Lagunitas Creek through the project area, where levees have been funneling the flow directly to the Bay. Historically, when the wetlands were not leveed, they undoubtedly played an integral role in maintaining the health of the Bay, which has deteriorated over the last century with excessive sedimentation, water quality problems, invasive species, and other issues. The San Francisco Regional Water Quality Control Board (RWQCB) declared waters of Tomales Bay and some of its creeks as impaired for sediment, pathogens, nutrients, and mercury under Section 303(d) of the Clean Water Act.
The Giacomini Wetlands Restoration Project conducted by Point Reyes National Seashore (Seashore) and the Point Reyes National Seashore Association (PRNSA) is reestablishing hydrologic processes and reconnecting floodwaters with floodplains in more than 550 acres at the head of Tomales Bay. This should improve water quality in the Bay, because anything carried by floodwaters can now be deposited on floodplains in the Giacomini Wetlands. Before entering the Bay, pollutants will be partially filtered out by the salt, brackish, and freshwater marsh communities that will re-establish in the area in coming years.
"This project is one of the most exciting and meaningful restoration efforts that we have ever observed," said Neysa King, watershed coordinator for the Tomales Bay Watershed Council. "Not only will the project restore a significant amount of tidal wetlands along Tomales Bay, but also we will be able to watch the changes that ensue as human-created structures are removed and the waters of the bay and creeks reclaim their natural areas."
The project will result in a substantial increase in habitat for marine, estuarine, and freshwater wildlife species, including endangered or threatened species and species of concern such as the coho salmon, steelhead trout, green sturgeon, tidewater goby, California clapper rail, black rail, common yellowthroat, and southwestern river otter. The wetland will also provide important habitat to migratory waterfowl and shorebirds, and nursery and foraging habitat for species such as seals, sharks, and rays that are typically found in the outer portions of Tomales Bay.
"This is the largest restoration project on the Central Coast," said Beth Huning, Coordinator of San Francisco Bay Joint Venture. "Point Reyes and Tomales Bay serve an important role as an interchange for birds between the Bay and the coast. It is imperative to do as much restoration along the coast as we possibly can, and this project is a big step forward."
Another benefit from the project is that increased floodwater retention on the Giacomini Wetlands floodplains may result in a significant decrease in flooding of the county road and private homes along the southern perimeter of the project area.
The Seashore has made an effort throughout this project to provide opportunities to experience and learn about the importance of wetlands and the restoration process. You are invited to enjoy this historic event through several activities scheduled during the weekend:
The Giacomini Wetlands Restoration Project area covers 563-acres of wetland and upland areas and an additional 63-acres on Olema Marsh, at the southern end of Tomales Bay. The area is within a UNESCO designated Biosphere Reserve and was named a Ramsar Wetland of International Importance in 2002. Restoration of the area will improve the condition and functionality of 50 percent of the wetlands in Tomales Bay.
A portion of this wetland complex was lost around the turn of the 20th century, when a levee was constructed across the mouth of Bear Valley and Olema Creeks for a road. Then in 1946, more levees were constructed around some of the remaining wetlands to increase milk production for the wartime effort. In 2000, the Giacomini family sold the ranch to the National Park Service (NPS), which acquired the property for the purpose of wetland restoration.
In designing this project, the Seashore did not attempt to re-create historic conditions or design a specific mix of wetland habitats. Instead, the project focused on enhancing the quality and functionality of wetlands within the Giacomini Ranch and Olema Marsh by reintroducing natural hydrologic and ecological processes. These processes include marine-influenced tidal action, freshwater flow from creeks, overbank flooding onto floodplains, and movement of the creek channel during storm events.
Restoration activities have involved removal of levees, creek bank stabilization, infrastructure, realignment of Tomasini creek, creation of tidal channels, retention or establishment of high tide refugia for endangered species, lowering topographically elevated areas, and grading.
Since 2004, PRNSA, a non-profit organization that provides support to the Seashore, has raised more than $6.0 million in non-NPS funds for implementing the restoration project. Funding sources include The Gordon and Betty Moore Foundation, North American Wetlands Conservation Act, Watershed Council of the State of California Water Control Board (Prop 50), State of California Wildlife Conservation Board, and the National Fish and Wildlife Foundation – Northern California Restoration Grant.
"The ecological effects of this project will be felt for many, many years to come," said King. "The very hard work of the Point Reyes National Seashore and its Association will reap rewards for us all that will include a richer and wilder future ahead."