King County prepares for flooding: More than 500 river facilities inspected for damage

This year the COVID-19 pandemic and the need for social distancing required field inspections take place with a different protocol to keep staff safe. Despite this additional challenge and the vast number of facilities to inventory, staff completed inspections on all 511 river facilities in one year – an activity normally done over a two-year cycle.

King County staff inspect a damaged revetment on the Snoqualmie River in July 2020.

The 2019-2020 flood season was one for the record books. The first flood event took place on the Snoqualmie River in October 2019 and the season concluded with a total of seven flood events having occurred in King County by the end of February 2020.

Damage was found on 136 facilities and plans for emergency repairs or longer-term improvements to remedy the damage are underway. This assessment and planning is critical in order to prepare for another flood season which began on October 1 of this year.

Flooding pictured from helicopter on the Cedar River in February 2020.

The flooding was due to extensive rain throughout western Washington. Average monthly rainfall totals throughout the region in December 2019, January and February were far greater than normal. After the widespread flood in February that received a Presidential Major Disaster Declaration, conducting post-flood inspections and triaging damage to river facilities was a high priority for the King County Flood Control District (Flood District).

River facilities, such as levees and revetments, play an important role in protecting people, neighborhoods and infrastructure against damage from erosion and flooding. The King County Water and Land Resources Division, as the primary service provider to the District, maintains more than 370 revetments and 130 levees across six river basins from the South Fork of the Skykomish River in the north to the White River in the south on the border with Pierce County.

Photo of a revetment on the Cedar River taken during an inspection visit in February 2020.

Each river facility is scheduled for inspection on a two-year cycle to look for any damage that could weaken its effectiveness. Inspections largely take place in the spring and summer or after a flood event and involve trained staff making careful observations of the riverbank facilities as well as floating the river in boats to identify potential problems.

Everyone in King County is encouraged to be flood ready. Information on what to do before, during and after a flood is available at kingcounty.gov/prepareforflooding.


About the King County Flood Control District

The King County Flood Control District is a special purpose government created to provide funding and policy oversight for flood protection projects and programs in King County. The Flood Control District’s Board is composed of the members of the King County Council. The Water and Land Resources Division of the King County Department of Natural Resources and Parks develops and implements the approved flood protection projects and programs.

About the King County Water and Land Resources Division

The Water and Land Resources Division works to protect the health and integrity of King County’s natural resources. Employees work to reduce flood risks, monitor water quality and restore wildlife habitat; manage, and reduce the harmful impacts from stormwater, noxious weeds and hazardous waste; create sustainable forestry and agriculture; and protect open space to support all of these efforts.

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KC Water and Land Resources Division

We protect, restore, and manage King County's water and land using the best available science, innovation, and through collaboration with our partners and the community.