| The Magazine of the CALIFORNIA ACADEMY OF SCIENCES |
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Habitats Flooding Room Gordy Slack Thirty years ago, slaughterhouses, tanning factories, and sanitation districts all discharged their wastes directly into the Napa River. It was unsafe for people, unfit for the plants and animals that had depended on it, unclean, and ugly. But the tide has changed for the Napa, and today this little river is arguably one of the most important waterways in the nation. The dedicated and diverse community of activists and agencies that has fought to resurrect it has not only improved its water quality and secured thousands of acres of wildlife habitat along its banks, but may also go down in history as having redefined America's approach to flood control. These activists, business people, homeowners, and bureaucrats staged a revolution against the U.S. Army Corps of Engineers, the federal agency responsible for flood control. But it was a non-violent revolution, one that eventually seduced the Corps into participating in a radical, ten-year, $220-million project that promises to do as much to restore and preserve the river's wildlife habitat as to protect property from frequent floods. The transformation of the Napa is important in itself, but ultimately its greatest impact may be as a model for dozens, or hundreds, of other rivers in similar situations around the world. And for its part, despite initial chaffing, the Corps is relishing its new identity as environmental good guy. Such a huge bureaucracy will take a long time to reform, but planting the notion that a living river may be less dangerous than a dead one is a profound accomplishment. This year, Corps leadership approached Congress requesting authorization and funding for a new program, called the Challenge 21 Initiative. The funds would be dedicated to "flood hazard mitigation and riverine ecosystem restoration." A decade ago, less than one half of one percent of the Corps' budget was used in environmental floodplain damage reduction projects. Today, about nine percent of the projects the Corps is researching involve habitat restoration. Four years ago, before the change of heart, the Corps proposed a project to line the Napa River with riprap for the seven or so miles that run through the city of Napa. The conservation community was not impressed. They had not worked for years to nurse the river back to life, just to bind it in a concrete straitjacket. But something had to be done. As the valley surrounding the Napa River is converted into vineyards, paved, and otherwise developed, the soil's effectiveness at absorbing runoff diminishes, and floods get more frequent and intense. Twenty-seven floods have hit Napa since the 1850s, and, over the last 40 years, floods have cost more than $540 million. In 1995, and again in early 1997, the river overflowed, turning downtown streets into churning tributaties, and forcing hundreds of people to abandon their homes. Flooding was already bad enough 30 years ago for Congress to allocate $80 million for flood control in the area. Since then, the Corps has presented three ways to spend the money. All of them would have deepened the river's channel, raised the levees on either side, lined those levees with concrete, and required frequent and disruptive dredging. The county rejected all three as environmentally and aesthetically unacceptable, preferring to weather the floods than drive a stake into the river's heart. For more than a century, the Corps had been trying to strong-arm rivers into compliance. The Mississippi River project, the biggest public works scheme in human history (twice the size of China's Great Wall), was the best, most glorious example of that approach. But the river mocked the Corps. In 1993, heavy rains overwhelmed the system, killing 48 people and causing $20 billion in property damage. Not only did towering levees and concrete culverts fail to keep the Mississippi within their walls, but they also made downstream floods more severe by blocking natural outlets for rising waters and creating faster flows. "The Mississippi River project's failure was a terrible shock for the Corps," says Moira Johnson-Block, president of Friends of the Napa River, a group long dedicated to the protection and restoration of the river. "It gave them a new humility." Despite the lessons learned on the Mississippi about the limits of incarcerating rivers in concrete, old ways die hard in the Army, and when the Corps presented its third and final proposal for the Napa River in 1995, it was another dominatrix: enlarge the channel, raise the banks, and line them with immovable objects. But the Corps' resolve had been weakened, and when a coalition of state and local governments, resource agencies, businesses, and environmental organizations banded together and proposed a radically different approach, the once hubristic Corps listened with more receptive ears. It wasn't just humility, though. Alone, the Corps didn't have the political clout to get its project through the necessary hoops, and time had run out. Not only were the floods disastrous, and getting worse, but this was the local community's last chance to take advantage of the 30-year-old, $80-million congressional funding appropriation. Congress had grown weary of allocating funds to a project that never materialized. Give us a plan everybody can work with, Congress said in effect, or forget the whole thing. After two years of relentless and intense research and negotiations, the Corps, 27 other government agencies, and 25 non-governmental organizations hammered out a revolutionary "living river" plan. Where the Corps had proposed floodwalls and levees, the coalition proposed terraced marshes and broad wetlands. Where the Corps had proposed dredging the river deeper to allow it to carry more water faster, the coalition wanted to make it wider, by returning much of its floodplain. Winning the Corps' cooperation for the plan was a big accomplishment, and getting hardened environmentalists, farmers, vintners, governments, and business owners to back the project is testament both to the tenacity of the participants and to their desperation. But agreement was only the first step. The coalition also needed about $110 million to supplement the money already allocated by the federal government. Hence, Measure A, on the ballot in Napa County in March 1998. Known as the "Living River Initiative," Measure A raised the county sales tax one half of a percent, amounting to about $6 million a year for the next 20 years. Passing a sales-tax hike in California requires a two-thirds majority and is rarely pulled off, since many voters reflexively vote against any new tax. But the coalition won over even fiscal conservatives, arguing that if the flood-control project worked, sparing the town from costly floods, it would save the community about $20 million a year, including project maintenance costs. Actually, it's misleading to say that the coalition "won over" anyone. Rather than having to convince every important constituency, the coalition just incorporated all of them. With virtually no organized opposition and wide community support, Measure A passed. Dave Dickson, the county's project manager for the flood-control plan and a self-described "consensus-building junkie," was largely responsible for building the coalition and keeping it together. The living river plan's operating principle is to let the river be itself. Rather than dominating it with elaborate corsets, brassieres, and foot bindings, the Corps will dress this stretch of the Napa in a simple green camisole. New concrete will be limited to confining short sections of the river near historic downtown buildings and helping control the river's most perilous curves. With the funds secured, work will begin in earnest next year, when the levees insulating about 500 acres of grazing lands to the south of the city are breached and restored to tidal marsh. Marsh restoration will require a lot of earth moving to create tidal terraces on each side of the river, but otherwise will be fairly passive. "The idea is to set up the habitats and let [in] those plants and animals that would and could come," says Jim Swanson, senior wildlife biologist for the California Department of Fish and Game. In addition to Mason's lilaeopsis, an endangered low-growing plant, and showy Indian clover, a plant proposed for the endangered species list, the restored marsh will also create new habitat for ailing aquatic species such as the Sacramento splittail, California steelhead, Delta smelt, and California red-legged frog. "The biggest winners are going to be the aquatic species: the fish, and the benthics," says Swanson. "But migrating waterfowl and other water birds will also benefit." The new marshes and riparian habitat will host herons, egrets, red-shouldered hawks, red-tailed hawks, kites, and other raptors. The new marshes may define an extreme north range for endangered salt marsh harvest mice and California clapper rails, too. For a tidal marsh, and a floodplain for that matter, a few feet of elevation can make a big difference, says Leslie Ferguson, an engineer and biologist working on the Napa River for the California State Regional Water Quality Control Board. And getting just the right heights for the terraces will pose a major challenge for the Corps' workers recreating the marshes. "If they don't adhere to those elevations, there could be different kinds of vegetation [than the restoration calls for], sedimentation, and geomorphic destabilization. We have to watch the construction very closely," says Ferguson. In the next few years Fish and Game will begin creating backup levees on the marshes. The lands on the far sides of the floodplains will still need flood protection, so in most places when a levee is removed, another one is built or reinforced, but further back from the river. The plan also calls for reforesting some riparian areas with native cottonwoods, sycamores, box elders, Oregon ash, and a variety of oaks and other trees. This will create good wildlife habitat while reducing bank erosion, minimizing sedimentation, and preventing weed and brush encroachment in channels. "Meander belts," open areas along the river's curves, will also be cleared and replanted with native vegetation to help absorb extra water during floods. In all, 16 houses, 25 mobile homes, 8 commercial buildings, and 13 warehouses will be removed from the river's banks and floodplains to give the river room to swell during floods. In addition, the project requires rebuilding seven bridges that will be higher and wider than existing bridges, and have streamlined profiles less affected by the high flows periodically rushing beneath them. At the place where Napa Creek meets the Napa River, near downtown, one of the project's few major plumbing fixtures will be installed. Called the "dry bypass," it will formalize the course the river now takes through town when it floods. Napa's founding fathers must have thought the little peninsula sticking into the river where it oxbows was both the beautiful and practical choice to settle, since it gave maximum exposure to the riverfront. But in its passion to get downstream, the flooding river can't be bothered with the detour and cuts right through town. The city and county will buy and remove the buildings, while the Corps will deepen the bypass channel and build bridges across it. Most of the time, when the river is not overflowing, the area will be dedicated to parks that can take an occasional swamping. The bypass had to be carefully designed not to disturb the hydrology of the downstream river. Again, great caution must be taken, says Ferguson, to construct the bypass right. "If the weirs aren't built properly, they could cause sediment to accumulate in the oxbow, destabilize the banks, and cause any number of unforeseen difficulties," she warns. Ferguson is particularly impressed with the City of Napa's dedication to restoring healthy steelhead trout habitat to Napa Creek. "The city deserves great praise. They are removing bridges, altering the course of certain streets, all because this is a steelhead rearing area. They are making major infrastructure changes to accommodate environmental values. That's really unusual and exciting." The seven-mile-long "living river" project will be the most visible component of the Napa River's overall restoration, but equally important improvements are taking place upriver, downriver, and throughout the valley. Phil Blake, Napa District Conservationist for the U.S. Department of Agriculture's Natural Resources Conservation Service, works with the Napa County Resources Conservation District (RCD) to oversee a watershed-wide education and regulation effort to protect the tributaries of the Napa River and to slow erosion and control pollution. The RCD developed the "Napa River Owner's Manual," a guide to good stewardship for landowners. The district brings creekside residents together, finds out what their interests are, and helps them create a conservation plan. On Huichica Creek, a tributary and home of the endangered California freshwater shrimp, for instance, there were concerns that too much water was being diverted for grape irrigation during the dry summer months. A dry creek is bad for the shrimp and for vintners who need to water their grapes. The RCD told residents, "You can work on a progressive approach to saving the shrimp, or have the resource agencies come in here and figure it out for you." They chose to do it themselves, and began coordinating their withdrawals to keep the creek flowing. They have also participated in efforts to control erosion, reintroduce native plants, and manage pesticides to sustain the watershed ecosystem. These novel programs are heartening, says Ferguson. However, her agency still considers the water quality of the upper watershed suspect. Others agree. In October, the Bay Keeper filed suit against the U.S. Environmental Protection Agency for failing to take stringent enough measures to protect the Napa River's water quality from upland erosion and pollution. Deforestation and other land conversion activities are the subjects of an ongoing public debate in Napa Valley. There is a huge incentive for property owners to remove oak and conifer forests to make room for grapes. Loss of forest means not only shrinking habitat in the higher areas, but also erosion and pollution in the tributaries and the river itself. Again, it is the citizens who are mobilizing, spearheaded by Friends of the Napa River, calling on legislators to enact a moratorium on deforestation in the watershed. Downriver, the state purchased about 10,000 acres of salt ponds from Cargill Corporation five years ago. The California Department of Fish and Game is overseeing the restoration of those ponds, which start about six miles south of the flood-control project and will run, in a long chain of salt marshes known as the Napa-Sonoma Marshes Wildlife Area, all the way to San Pablo Bay. Meanwhile, the U.S. Fish and Wildlife Service is restoring to marshland 1,500 acres of farmland that had been created from reclaimed tidal lands. Called the Cullinan Ranch, it is visible from Highway 37. Though it now floods in winter, creating seasonal wetlands, Fish and Wildlife will begin to blast the levees and restore it to tidal marsh later this year. All together, these projects make a lot of new, irresistible habitat. "The North-Bay area may well become the richest repository of waterfowl and marsh habitat in California," says Blake. Continuous habitat is the trick to restoring a "living river," says Swanson. These new projects will create a continuity along the river from San Pablo Bay to the river's tributaries and headwaters. There will also be lateral continuity, connecting the river to surrounding shallow water mudflats, tidal marsh, emergent vegetation, and upland riparian habitats. The environment will gain, but what about flood control? Well, the Corps' engineers think the flood-control portion of the project will work just fine. "There's no reason flood-control values have to compromise environmental values," says Rick Reinhardt, the Corps' technical manager for the project. "Restoring the river's natural water-absorption mechanisms is functional from a flood-control standpoint and there are really no extra costs." These are amazing words coming from an agency whose main adversary has been America's free-flowing rivers. If it does work, every river community in the world will have reason to celebrate. And if it doesn't work? We already know how to waste money on a flood-control system that neither worked nor respected the river's environmental values. If the living river approach fails to quell flood damage, at least it will help bring back steelhead and Delta smelt, support vast flocks of migrating birds, and move the community to invest in erosion control and sane and measured development. Better a vibrant, healthy, flooded Napa Valley than a dead flooded one. Gordy Slack is Associate Editor of California Wild. |
Winter 1999
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