The observations compiled here reflect a shared commitment among Tribes, local governments, landowners, state agencies, nonprofits, and technical experts. Floodplains by Design is grateful to every partner who helped plan, design, construct, monitor, and steward these projects, and to those who responded during the storms to protect lives and property. Many project partners and the greater integrated floodplain management network shared inspiring examples of how long-term mitigation work showed up during the December 2025 floods.

Lower Russell Levee Setback City of Kent

The Lower Russell Levee Setback on the Green River performed exactly as designed. Floodwaters stayed fully contained within the setback levee and floodplain with room to spare. This project gave the river space to spread out and slow down while reducing pressure on downstream infrastructure.

Naches River N9 Setback

In Yakima County, the Naches River reached its third-highest recorded stage and stayed high for nearly two weeks. At the N9 Setback site, previously removed levees and newly connected floodplains absorbed the majority of the flow that otherwise would have attacked the opposite bank. Flood fighting across the opposite bank was not required, reducing stress on staff, emergency response needs, and public safety risks. As one local partner reflected afterward, the reduced need for overnight monitoring, emergency response hours, and flood anxiety made the value of integrated floodplain management unmistakably clear.

Lower Dungeness River Floodplain Restoration Project

During the flood event, the river flowed into its historic floodplain, spreading out across more than 50 acres of restored wetland and side channel habitat. Water slowed and dispersed across the reconnected floodplain rather than remaining confined in a narrow corridor. The restored “Schoolhouse Channel,” which reactivated during high flows, is now functioning as a primary side channel. ESA-listed Chinook, summer chum, and steelhead have been observed spawning there, along with pink and coho salmon. ESA-listed trumpeter swans have also been documented using the new floodplain habitat. By reconnecting the river to its historic floodplain, the project increased flood storage capacity, buffered downstream impacts, and created long-term ecological benefits. The result is a system that absorbs flood energy more naturally while supporting fish, wildlife, and the surrounding community.