Once one of most extensive wetland areas in North America, the edges of the San Francisco Bay have become covered with farms, industry, and urban areas, squeezing out the marches and their animal and plant occupants.
But at the lower end of the Napa River, a remarkable effort is underway to undo a century and half of damage to the once-thriving marshes.
The California Department of Fish and Wildlife, which owns the Napa-Sonoma Marshes Wildlife Area, has been gradually increasing the size of the tidal marshes with planned, deliberate restoration and flooding.
The newly enlarged marsh area provides local residents and visitors with opportunities to boat, fish, hunt, hike, and observe wildlife. All activities on state lands are regulated.
The effort to restore the marshes also reduces agricultural pollution in the San Francisco Bay, gives local students a chance to participate in installing native plants, increases habitats for endangered species, particularly those that use the marshes as a feeding area during seasonal migrations, and connects to county-restored wetlands downtown to create a broader corridor for local wildlife.
The marshes currently encompass approximately 15,200 acres of baylands, tidal sloughs, and wetland habitat, located north of San Pablo Bay between the Napa River and Sonoma Creek. Most of the area is accessible only by boat.
Larry Wyckoff, a senior environmental scientist with the Department, said the enlargement is taking place across the 15,000 acres of Department land on different, non-contiguous parcels.
“Our long-term goal is to restore these parcels of the marsh to its pre-existing condition, before they were used for salt ponds or as farmland,” said Wyckoff. “The largest parcel is from the former Cargill Salt Facility. The desalination process for the remaining salt pond will take between 10 and 15 years. Most of the other department properties are in Napa, with a few in Sonoma County and a few more in Solano County.”
Wyckoff said the new areas of the marsh were made into parcels between the early 1930s and 1950s.
“We’re restoring them to a mosaic of habitats, including tidal salt and brackish water marshes, managed ponds, seasonal wetlands, and adjacent uplands. (These) will benefit rare, threatened, and endangered species as well as a broad range of (other) fish, wildlife, and plant species,” said Wyckoff.
Wyckoff said the multi-year process begins with the department looking at available water to flood an area “using hydrodynamic modeling. We identify the historic slough channels to use as a starting point for breach locations.”
“After we learn where the water used to go, we go through the regulatory processes and the California Environmental Quality Act (CEQA). Then we plan, design, and begin construction. We’re re-contouring the wetlands, creating sinuous channels. We also breach the existing levees at appropriate locations,” said Wyckoff.
Wyckoff said the water in the restored areas is coming from San Pablo Bay, the Napa River, Sonoma Creek, and the Petaluma River.
The money for this project is coming from the state through the California Department of Fish and Wildlife, the California Coastal Conservancy, the California Wildlife Conservation Board, and money from a litigation settlement fund from Shell Oil to compensate for its past environmental mishaps in the state, said Wyckoff.
Local restoration efforts
The department’s efforts to change the landscape coincide with Napa County’s work to perform habitat restoration and flood-risk reduction.
Richard Thomasser, watershed and flood control operations manager for Napa County Flood Control and Water Conservation District, said the district’s work associated with the flood project along the Napa River connects downtown with the Napa-Sonoma Marshes Wildlife Area.
“There’s a habitat connection from downtown Napa to those larger marshes in the Wildlife Area. We have restored over 900 acres of wetlands, which used to be hay fields leveed off from the Napa River. In 2001, we breached those levees and allowed the Napa River to tidally inundate those areas. We also created marsh and floodplain terraces along the Napa River downtown,” said Thomasser.
He said these inter-related areas of restored habitat create a flyway for migratory birds.
“The fact that the county and the state have done restoration efforts relatively close in time and near one another means that you’ve got a corridor of habitat which is contiguous instead of little, broken up pieces. Now, critters that live in the area don’t have to run a gauntlet to find food and habitat to survive,” said Thomasser.
He said the department and the district engage in separate efforts to monitor wildlife such as native plants and endangered species, but are in frequent communication with one another.
Don Brubaker, refuge manager at San Pablo Bay National Wildlife Refuge, which borders parts of the Napa-Sonoma Marshes Wildlife Area, said the state’s restoration complements similar work by the refuge.
“We’re restoring a portion of Haire Ranch on the northeast edge of Skaggs Island. The restoration was funded by the Natural Resources Conservation Service through the U.S. Department of Agriculture. Restorations like these are driven by when money becomes available,” said Brubaker.
He said the department and the refuge share goals of managing the marshes effectively, ensuring the health of population of waterfowl, migratory birds, and endangered species like the Salt Marsh Harvest Mouse, and engaging in law enforcement to prevent theft of resources and unauthorized use.
“They patrol their lands and our lands as well, letting us know if there’s anything like a cut chain on a fence. It’s nice to have those eyes and ears out there,” said Brubaker.
David Thomson, senior ecologist at the San Francisco Bay Bird Observatory, a nonprofit organization dedicated to avian observation and research, said birds are one of the first types of wildlife to flock back to a restored area en masse.
Some birds that are likely to be present in greater numbers in the Napa-Sonoma Marshes Wildlife Area because of the restoration are three federally endangered species, the Ridgeway’s Rail, the Black Rail, and the Western Snowy Plover. California species of special concern that may also increase in the area include the Samuels Song Sparrow and the San Francisco Common Yellowthroat.
Thomson said the restoration will help Napa Valley minimize the impact of agricultural pollution.
“Napa Valley … has a considerable amount of agriculture. The salt marshes (will) help clean the water flowing down the Napa River before it reaches the bay. This (will) also include urban runoff,” said Thomson.
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The Napa-Sonoma Marshes Wildlife Area is part of the San Francisco Bay Estuary, he said.
“(This estuary) is the largest (estuary) on the Pacific coast of (both continents of) the Americas. Wildlife biologists consider it of ‘hemispherical importance,’ meaning it is critical to the survival of species in the Northern hemisphere of the planet. Part of this importance … is due to wetland loss throughout California. Ninety percent of our state’s wetlands have been lost to development in the Central Valley of California. The species that once used those wetlands have shifted to our estuary for habitat. That makes the estuary even more important that it once was,” said Thomson.
Walter Heady, coastal marine ecologist with The Nature Conservancy, said one of the best features of the San Francisco Bay Estuary for wildlife is that there is not much infrastructure and built environment around it.
“If a habitat has its back against a concrete wall, it doesn’t have anywhere to go into. The San Francisco Bay Estuary’s wetlands, salt ponds, and upland terrestrial brush back up to agricultural areas and open space,” said Heady.
He said the fact that parts of the San Francisco Bay Estuary are separated from towns and cities help species like migratory birds survive.
“Birds need to be able to stop along their flight to sleep, rest, and eat. Sometimes they do this for weeks. In addition, this habitat is incredibly important for fish and invertebrates. The ‘nursery’ of a large estuary allows for extremely high growth rates and much less risk of being eaten,” said Heady.
Enlarging these marshes also helps prevent flooding of the built environment, including roads, he said.
“When a salt marsh is bigger, that creates a larger area for waves of salt water to diminish in size and not get to the road. The topography and the roughness of the plants in the marshes slow wave action. All the sediment in the water then settles into the marsh plain, preventing erosive forces from washing away roads,” said Heady.
Local students assist with restoration work
John Parodi, restoration manager for Point Blue Conservation Sciences’ Students and Teachers Restoring a Watershed (STRAW) program, said Point Blue has been working for the past 12 years to help students and teachers get involved in protecting the wetlands. Point Blue is a Petaluma-based nonprofit focused on wildlife conservation, restoration, and research.
STRAW restoration days typically involve students replanting native vegetation at key points in the environment where diversity is low and erosion is likely to occur. One environment that STRAW has worked on is the Napa-Sonoma Salt Marshes Wildlife Area.
He said levee edges can be particularly bare areas about which Point Blue has had concern. Bare areas are not productive for wildlife. Replanting levees allows more vegetation and animal life to thrive, sometimes without human-aided efforts.
Valley Oak High School science teacher Julie Lovie said she and her students have participated in STRAW workshops in the Napa-Sonoma Marshes Wildlife Area for the past five years.
Lovie teaches 11th and 12th graders at this public continuing education high school in Napa.
“I think it’s important for my students to be able to contribute to the community and have that power to improve the environment. They also learn from watching science come alive. Watching them work together as a group was incredible. I am signed up to participate in the workshops again this year,” said Lovie.
The biannual workshops in the fall and early spring “are the kind of thing I look for to get my students involved,” Lovie said.
“At first, they’re a little resistant to grab a shovel and get dirty. Then they really get into it. For some students, (activities like this) level the playing field. Some of them have experience with this (planting vegetation). (Being able to contribute) is a huge thing for them. They understand that they are really accomplishing something,” said Lovie.
Shari Gardner, ecologist and former executive director of Friends of the Napa River, is thrilled that the restoration will improve the health of the river and Bay while allowing the community more access to wetland habitats.
“The marshland is the lower 15 miles of the Napa River. Much of the marshland is estuarine, fed by freshwater coming down the river through the Napa River watershed. (The marshland is also fed) by water from the San Francisco Bay, which comes up the river with the twice daily high tides. The whole area is really dynamic. The marshes clean the water and provide critical habitat for juvenile steelhead and salmon, white sturgeon, migratory shorebirds, diving ducks, and osprey,” said Gardner.
She said seeing the restored lands as well as the restoration in action helps to change peoples’ attitudes about the need for habitat conservation and protection.
“With the old salt ponds being flooded and the toxic levels of salt slowly being diluted, we have a chance to restore the function of this damaged ecosystem. It is wonderful that marshlands close to the river are becoming more accessible. Now there are more opportunities to get out birdwatching, fishing, bicycling and walking. The more people get to interact with the river, the more they’re going to love it,” she said.
Gardner said paddlers on the river and channels in the marshlands should mind the tides.
“The tides are really powerful. When the tide’s doing you a favor, it’s fantastic and dreamy. If you’re paddling against the tide, it can be really difficult to make any headway. It’s also wise to watch out for the shallows at low tide. Your boat could get stuck in thick mud,” said Gardner.
Bob Fisher, owner of Wombat Charters, a Napa boat tour agency that tours the Napa-Sonoma Marshes Wildlife Area, said individuals who travel into the marshes via boat are already able to see many benefits.
“In the last 10 years, different agencies have already done a lot of restoration. This is just an expansion of that project. You will be able to see more birds, including red-tail hawks, blue herons, white pelicans, brown pelicans, and great white egrets. I’ve also seen river otters in slews off the Napa River. There are now more striped bass and sturgeon. I’ve even seen sturgeon jump from the water high into the air,” said Fisher.
“The tide makes the water in the marshes not just sit there in a permanent static state. That water goes in every six hours, filtering the marshes so the water becomes cleaner. I’ve also cut a striped bass open and seen it packed full of shrimp. Shrimp feed on grasses, which means the river system is very healthy,” said Fisher.
He said visitors and locals are amazed at the beauty of the marshes.
“This is the biggest-kept secret in Napa Valley. There’s a lot of people in Napa and Sonoma counties who have no idea this exists. Tourists sometimes see the Napa River downtown, but that’s all they know about this environment. Hopefully with the expansion of the restoration, all that is going to change,” said Fisher.