By John Carlon, President
The mission of River Partners is to “create wildlife habitat for the benefit of people and the environment.” To this end, over the last 15 years we have restored more than 8,000 acres of floodplain habitat. From the beginning, our organization has embraced the concept of multi-benefit projects – projects that benefit public safety, recreational opportunities, and the environment.
Given our mission and history, River Partners was very encouraged to learn that the Central Valley Flood Protection Board recently adopted the following resolution:
“Wherever feasible, improvements to the State Plan for Flood Control should … provide for multiple benefits through projects designed to improve public safety while achieving other benefits, such as restoration of ecosystem functions and habitats within the flood management system.”
This resolution represents a significant shift in approach within the flood control community and opens the door to exciting opportunities for our organization. River Partners’ innovative habitat projects on California’s two longest rivers, the Sacramento and San Joaquin, are living testament that multiple benefit projects can be successfully implemented. River Partners’ projects can also provide a framework for collaboration that will be required under this new multi-benefit approach to flood management in the state.
Californians expect healthy rivers and flood safe communities. The multi-benefit resolution adopted by the Central Valley Flood Protection Board is direction for everyone working in the floodplain to align their programs and projects, to work together, and to comply with all existing codes and regulations.
The Bear River Levee Setback Project is one successful example of this approach in action. In 2005, 9,600 feet of levees were set back at the confluence of the Bear and Feather Rivers and 600 acres of flood-prone farmland were reconnected to the floodplain. The results have been impressive:
- Reduced Flood Risk. The new setback levee provided adjoining communities with 200-year flood protection. The old levees built in the late 1800’s were made of whatever material was at hand, clay and soil or sand and gravel. They were constructed over old creek beds, gravel bars, wetlands, and sand splays – not ideal conditions for the foundation of a levee. The new state-of-the-art setback levee is situated on solid ground, with sound foundations, constructed of engineered materials. By moving back away from the river, the new levee significantly increases the capacity of the river channel. This increase in channel capacity lowers the height of the river and decreases the velocity of flows during flood events.
- Improved Ecosystem Function. When the old levee was demolished and the new setback levee was constructed, an additional 600 acres of floodplain were reconnected to the river. Land that used to be on the dry side of the levee is now part of the active floodplain, inundated at 3-year intervals. With funding from California Department of Fish and Game (now Department of Fish and Wildlife), River Partners restored this property into riparian forest and grasslands. Salmon, Swainson’s hawk, and several other endangered species are directly benefiting from this newly restored habitat.
- Increased Recreational Opportunities. The Bear River Levee Setback Project is located at the confluence of the Bear and Feather Rivers and is adjacent to the Lake of the Woods State Wildlife Area. The 600-acre setback area is ideally suited for hunting, hiking, horseback riding, and bird watching. With over three miles of river access it also provides opportunities for canoeing, swimming, and fishing.
- Improvements in Water Quality. Before the setback levee was constructed, a significant portion of the floodplain within the old river channel was farmed. Walnuts, prunes, and field crops were produced on the land that is now on the wet-side of the levee. Herbicides, pesticides, and fertilizers were part of the normal farming practices, so when heavy rains occurred, there was always the risk that these agricultural chemicals could migrate into the river. Now that this land has been repurposed from agriculture to habitat, the agricultural chemical applications have stopped and the riparian forests and native grasslands act as a buffer between the river and neighboring farming operations.
- Increases in Water Supply Reliability. On average, farming the walnuts, prunes, and field crops in the setback area required roughly 2,400 acre-feet of irrigation water per year. Now that the property has been restored and agriculture discontinued, this water is no longer being removed from the system. In addition, when floods occur the larger channel capacity increases the opportunity (greater surface area over a longer duration of time) for more water to infiltrate into the ground and recharge the aquifer.
- Climate Change. Moving the levee back and expanding the channel capacity of the Bear River addressed the potential for climate change in two ways. First, it improves the ability of the system to absorb floodwaters from more frequent and severe events and second, the riparian habitat that River Partners planted on the site will sequester over 150,000 tons of carbon by the time the forest reaches full maturity.
Notwithstanding all of these tangible results, the real genius of moving the levee back along the Bear River is that everyone came together to make this multi-benefit project work. Local leaders emerged armed with a vision of what they wanted for their community and they enlisted the support of local, state, and federal partners. The Bear River Setback Levee Project was funded by many sources, designed for many purposes, and implemented by many partners. Three Rivers Levee Improvement Authority, Yuba County, Reclamation District 784, the Department of Water Resources, Army Corps of Engineers, US Fish and Wildlife Service, California Department of Fish and Wildlife, the Wildlife Conservation Board, and River Partners all contributed to the success of this effort.
The end result of this collaborative effort is a multi-benefit project that improves public safety, restores the environment, enhances the local community, and provides a model for other similar projects throughout the Central Valley.