Floodplains

Floodplains are the areas of low-lying ground adjacent to rivers, formed mainly of nutrient-rich river sediments and subject to flooding after storms and heavy snowmelt.

Source: Floodplains by Design

Aerial photo of Hansen Creek restoration site in Skagit County, WA. October 15, 2010. Photo: Kari Neumeyer/NWIFC

OVERVIEW

Nature inspires new approach to flood control

Scientists are rethinking floodplain management in Puget Sound. Can we have our farms and salmon too?

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Two people operating a bulldozer at the intersection of two flooded streets in Sumas, Washington. In the background, partially submerged cars are parked in front of the library.
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2016 aerial view of completed Calistoga Reach levee project in Orting, WA. Image courtesy: CSI Drone Solutions and Washington Rock Quarries, Inc. Video: https://www.youtube.com/watch?v=2H_NK6U2_zw
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Floodplain projects open doors to fewer floods and more salmon

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Submerged marsh in Fisher Slough. Image courtesy of NOAA.
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Floodplains by Design

Floodplains by Design identifies floodplains in Puget Sound with multiple benefit potential and use information on flood risk to inform ecosystem restoration. 

Aerial view of Interstate 5 stretching across a large area of land covered by brown flood waters from the Nooksack River in the foreground with mountains and Puget Sound in the distance and grey skies above.
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Studies target increasing flood risks

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A beaver swimming in a pond with vegetation in the background.
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Winter scene of marsh at high tide two conifer trees reflected on water in the foreground; snow covered mountain in the background.
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View of river with reflection of clouds and vegetation
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Tidal forest as viewed from an inner waterway of Otter Island in the Snohomish River estuary. Photo: Jeff Rice/PSI
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Cassells Point, Duwamish River, WA, ca. 1891. View is to the east, with streetcar bridge crossing the Duwamish River near South Park in the background. Photo credit: University of Washington Special Collections, Frank Laroche Photograph Collection.
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Dean Toba, a scientific technician with the Washington Department of Fish and Wildlife, operates the agency’s screw trap on the Skagit River. The trap helps biologists estimate the number of juvenile salmon leaving the river each year. Photo: Christopher Dunagan, PSI
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Are we making progress on salmon recovery?

In recent decades, hundreds of millions of dollars have been spent to restore habitat for Puget Sound salmon. In this article, we look at how scientists are gauging their progress. Are environmental conditions improving or getting worse? The answer may depend on where you look and who you ask.

Fir Island Farms habitat restoration monitoring in Skagit County. Project provides rearing habitat for young threatened Chinook salmon along with other wildlife. Copyright: Bob Friel
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Birch Bay. Photo by Jeff Rice
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Report cover for State of Knowledge: Climate Change in Puget Sound
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McLane Creek Basin water resource protection study report cover
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Black Lake Basin water resource protection study report cover
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Puget Sound portion of a 1798 chart showing "part of the coast of N.W. America : with the tracks of His Majesty's sloop Discovery and armed tender Chatham / commanded by George Vancouver, Esqr. and prepared under his immediate inspection by Lieut. Joseph Baker." Credit: Library of Congress, Geography and Map Division.
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Puget Sound is the second largest estuary in the contiguous United States. Today, we understand that estuaries — where freshwater and saltwater merge — are among the most productive places for life to exist.

Hansen Creek Alluvial Fan and Wetland restoration project (Poster #1)
7/28/2015

Hansen Creek alluvial fan and wetland restoration project

Habitat restoration was undertaken in 2009-2010 on lower Hansen Creek, Washington. The project converted 140 acres of isolated floodplain into 53 acres of alluvial fan and 87 acres of flow-through wetlands.