Floodplain and Wetlands Restoration Projects
Coyote Creek, California
After major flooding in 1983, the Santa Clara Valley Water District sought approval for levee setbacks and bypass channels. The project was completed in 1995 and is credited for reducing flooding in 1997. According to the Santa Clara Valley Water District, flood waters would have been 40 percent faster and water volume would have been 57 percent higher without these improvements.
Napa River, California
Residents along the Napa River have endured about 30 floods in the last 150 years. Costs associated with floods in the last 40 years alone totaled more than $540 million. In 1998, local advocates convinced the Corps to adopt a flood control plan that worked with nature by demonstrating that the community could save $20 million a year with their “Living River Initiative.” This modern plan called for replacing the Corps’ old-style proposed floodwalls and levees with terraced marshes, wider wetland barriers, and restored riparian zones. About 500 acres of previously drained farmland were returned to marshland.
Cache River, Illinois
Channelized, dredged, diverted, and leveed since the early 1900s, the Cache River today has lost 91 percent of its historic wetlands, leaving just 472,800 acres of its once five million-acre floodplain. Friends of the Cache, local landowners, the Nature Conservancy, and a variety of government agencies formed a partnership in 1995 that has resulted in the restoration of 9,000 acres of wetlands, reducing erosion and sedimentation, improving water quality, decreasing flooding, and allowing wildlife to flourish. The success of this project has inspired efforts to restore small creeks in the watershed to their original channels.
Iowa River, Iowa
After the historic 1993 floods, communities in east-central Iowa sought to change the land use along the Iowa River. Flooding easements were purchased on 12,000 acres along the 45-mile river corridor. Over the past decade, local communities are estimated to have saved $7.6 million in flood damages.
Charles River, Massachusetts
The $10 million Charles River Natural Valley Storage Project involved purchasing 8,500 acres of wetlands, which had the storage capacity for 50,000 acre feet of water, in the upper river. The National Wildlife Federation estimated loss of these wetlands would have created about $17 million in flood losses each year.
Missouri River, Missouri
Severe flooding throughout the 1990s led local citizens to seek natural alternatives to structural flood control measures. Through a combination of fee title acquisition and easement acquisition, 19,000 acres on a 49 mile stretch between Boonville and Jefferson City, Missouri were purchased and set aside as flood overflow areas, including nearly 6,000 acres that were previously enclosed by levees. According to the Natural Resource Conservation Service, the U.S. Army Corps of Engineers (Corps) estimated that such reconnections of the river with its floodplain reduced flood levels in 1998 by about four feet.
Red River, North Dakota and Minnesota
Following severe flooding in the spring of 1997, the cities of Grand Forks, North Dakota and East Grand Forks, Minnesota initiated a program to set back levees and acquire flood-prone property to create a 2,200-acre greenway along the Red River between the two cities.
Mingo Creek, Oklahoma
The city of Tulsa saw the worst flood in its history in 1984. Five of the 14 deaths and $125 million of the $180 million in flood damage occurred along Mingo Creek. Rejecting the Corps’ plan to build five structural detention sites, a team of civil engineers, urban planners, and landscape architects devised an alternative that included preserving open space, creating permanent lakes, and relocating some buildings. Tulsa’s flood insurance rates subsequently decreased by 25 percent and repetitive loss properties have declined from 93 in 1984 to just five in 1995.
Duffy’s Marsh, Wisconsin
Located in Marquette County, Wisconsin, the Duffy’s Marsh restoration project encompasses about 1,500 acres of open water, grassy wetland, and upland. The restoration work primarily involved filling agricultural ditches that drained the land. The marsh now holds approximately 55 million cubic feet of water.