The Coastal Wetlands of Southern California

This is a historial post from Hiking the California Trail, a 1998/2002 book set by Bob Lorentz and Richard Nichols. Where possible an update has been provided.

In the last 150 years, thousands of acres of California’s marine estuaries disappeared under the development of harbors, marinas, industrial building and housing tracts. Wetlands became the Los Angeles, Long Beach and San Diego Harbors. Downtown San Francisco and the Marina District sit atop bay mud, much of San Francisco Bay wetlands has been converted to salt evaporation ponds, Del Mar Racetrack sits atop a wetlands in San Diego, luxury yachts float in marinas scooped out of pickleweed flats. In all, 80% of California’s coastal wetlands have vanished.

The wetlands of southern California remain among the most diverse and threatened in the world. Several dozen ecosystems from Point Conception to the Mexican border continually suffer pollution and the threat of filling. The Mediterranean climate, young geologic features, and infrequent but strong winter storms create conditions for distinctive coastal wetlands species. These conditions include wide fluctuations in water levels, salinity, oxygen, and temperature, sometimes magnified by human intervention. The resulting species with unique adaptive traits make the wetlands exceptionally worthy of conservation. The clapper rail, an endangered bird, exemplifies special adaptation. It builds a platform nest tethered to cord grass, allowing it to rise and fall with varying water levels. The native Belding’s savannah sparrow, which nests in the pickleweed marsh, can drink sea water.

Even where wetlands enjoy protection, uplands development generates erosion and pollution that heavily impacts the ecosystem. The degradation puts tremendous pressure on wildlife, exterminating many species and endangering others.

The importance of wetlands, the most productive ecosystems of any in the world, cannot be over emphasized. They create the base of the food chain for many species, serving as spawning and nesting site, incubator and nursery to many kinds of birds, fish and crustaceans. The south coast wetlands, an integral part of the Pacific Flyway, hosts one of the largest bird migrations on the planet. Wetlands also serve as a filter for storm water, releasing clean water to the ocean.

In spite of the dire condition of wetlands, and even though in recent years laws more strongly protect them, battles still rage in some locations over development in wetlands and pollution from upland. In Orange County, the foothills above the Upper Newport Bay estuary suffer clearing for development by the Irvine Company, among others, exposing the soil and creating silt-laden runoff that flows directly into the bay down channelized creeks. It’s estimated that just one creek deposited about 400,000 cubic yards of silt into the bay in 1993. At the 1000-acre Ballona wetlands, the last significant piece left in Los Angeles, developers obtained approval for dense development on the inland part of the wetlands. Approvals allow thousands of residential units and millions of square feet of commercial space in spite of intense opposition by environmental groups and thousands of local residents. The Wetlands Action Network filed suit to stop the project based on a variety of environmental issues including the question of runoff. Development remains stalled by the suit, giving Ballona supporters a fighting chance to finally save this vital parcel.

The Bolsa Chica wetlands in Orange County contain 1300 acres of historic wetlands and 300 acres of mesa. For 30 years citizens, environmental groups, agencies and developers have battled over the fate of the site. The Amigos de Bolsa Chica wanted the entire site saved for its environmental value. Developers wanted to build, even in wetlands, although it goes against the Coastal Act. Over the years such projects as a nuclear powered desalinization plant, an international airport, and a marina with thousands of homes were proposed. In 1996 the Coastal Commission approved 900 houses on 180 acres of wetlands and 2,500 units on the mesa in spite of the Coastal Act and staff recommendations. Citizen groups sued, giving state and local agencies time to come up with a plan to purchase the area from the Koll Real Estate Group. In 1997 the Ports of Los Angeles and Long Beach agreed to provide almost $68 million in funding to buy 880 acres of wetlands as mitigation for port development. Plans call for eventual restoration of the entire remaining wetlands. As of this writing the fate of the remaining uplands is undecided.

Wetlands endure as a prized development commodity on the southern coast. Expanding population, pressure to develop, and increased pollution from inland sources could spell the end of the southern California coastal ecosystems and the abundant life they contain. Local, state and federal agencies must begin comprehensive, coordinated planning to permanently end development in wetlands, end damage from inland sources, and seriously start the critical process of reclamation and restoration.


Originally Published in Hiking the California Coastal Trail: Guide to Walking the Golden State's Beaches and Bluff from Border to Border - Volume Two: Monterey to Mexico by Bob Lorentzen and Richard Nichols
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