By Steven Schauer, Deputy Executive Director, and King County Staff

In recent months, the King County Flood Control District shared a three-part blog series highlighting emergency flood response projects (Cedar River, Green River, and White River) funded through a supplemental budget amendment approved by the District Board of Supervisors on February 10, 2026. Those projects focused on emergency actions taken during the historic December 2025 flood to protect people, property, and critical infrastructure as floodwaters surged across King County.

This is the second of new three-part blog series also focuses on the supplemental budget amendment approved on February 10, 2026, but highlights a different category of work: projects of immediate concern that were implemented after the worst of the flooding had passed. While emergency response projects were carried out during the flood itself, these immediate repair projects took place from late December 2025 through April 2026 to address damage caused by the flooding and restore critical flood protection facilities before additional storms could occur.

These immediate repairs were especially important because King County remained in the middle of flood season. Damaged levees, revetments, and other flood risk reduction facilities needed to be repaired quickly to maintain protection for communities, infrastructure, and the environment. The importance of these immediate repairs became clear when additional flooding occurred in March 2026, demonstrating the need to restore damaged facilities as quickly as possible.

This second blog in the series highlights immediate repair projects funded on the Green River.

A Historic Flooding Event

Flooding has always been part of life in King County, but the 2025–2026 flood season demonstrated just how powerful and destructive our rivers can become.

Between December 8 and December 30, 2025, King County experienced a generational flood event that tested flood protection infrastructure, emergency response systems, and communities throughout the region. The flood damaged nearly 170 flood protection facilities across King County, underscoring the importance of maintaining and improving the more than 500 flood risk reduction facilities that help protect people, property, infrastructure, salmon habitat, and the environment.

Despite the severity of the flooding, there was no loss of life from flooding in King County, which is a testament to the dedication of emergency responders, local governments, residents, and decades of investment in flood risk reduction.

Supporting Immediate Recovery

Recognizing the urgent need to restore damaged flood protection facilities, the District Board of Supervisors approved nearly $7.3 million in February 2026 for immediate repair projects completed between late December 2025 and April 2026.

Of that funding, $296,969 supported five immediate repair projects on the Green River. These projects addressed damage that posed risks to levees, public infrastructure, and nearby communities while helping ensure flood risk reduction facilities remained functional during the remainder of the flood season.

Briscoe School Levee Emergency Repair

One of the projects on the Green River funded through the supplemental budget addressed sinkholes and voids that developed on the riverward face of the Briscoe School Levee near River Mile 16.71 during the December flood.

Emergency repairs were made at this site, and King County engineers determined that further immediate repairs were necessary to maintain flood protection during future high-flow events. King County crews removed damaged soil, reconstructed the levee using compacted fill, restored disturbed areas with topsoil and mulch, and repaved the trail located on top of the levee. The repairs restored the levee to its pre-flood condition and strengthened its ability to withstand future flood events.

This immediate project received $26,740 in supplemental funding.

Desimone Levee Breach Emergency Repair

One of the most significant repairs on the Green River occurred at the Desimone Levee near River Mile 15, where floodwaters caused a 20-foot-wide breach in the levee on December 15, 2025.

Emergency repairs began instantly to stop water from flowing through the breach and restore levee integrity. To stabilize the damaged area, crews from multiple government agencies worked together using supersacks (i.e., a large, heavy-duty industrial bags that can hold up to 4,400 pounds of sand), quarry spalls (i.e., large, fractured chunks of rock, typically ranging from 2 to 8 inches in diameter), crushed rock, and riprap (i.e., large, loose, stones, concrete chunks, or rubble used to armor riverbanks against erosion).

Additional immediate repairs completed in late December and early January included backfilling the breach, restoring trail access, constructing a seepage blanket (i.e., a layer of material installed to manage groundwater movement), and repairing infrastructure damaged during emergency response activities.

This immediate project received $109,264 in supplemental funding.

Pipeline and Okimoto Levees Emergency Repair

During the December flood event, seepage was discovered where the Pipeline and Okimoto levees meet near River Mile 21.9. Emergency repairs were implemented during the flood.

To reduce the risk of future damage and maintain flood protection, King County crews implemented an additional immediate repair by installing geosynthetic fabric and covering it with crushed surface base course (i.e., crushed stone or gravel) along approximately 230 feet of the levee system. The immediate repair reinforced the levees and helped address seepage concerns before additional flooding could occur.

This immediate project received $71,143 in supplemental funding.

Somes-Dolan Levee Emergency Repair

Flooding during the December event caused water to overtop portions of the old Green River Trail and engage the riverward side of the Somes-Dolan Levee near River Mile 19.35.

Engineers identified seepage on the landward side of the levee and determined that immediate action was necessary to prevent potential failure. Emergency repairs took place, followed by additional immediate repairs, which included installing a seepage blanket made of geotextile fabric, crushed surface base course, and sand-filled supersacks. These improvements helped stabilize the levee and protect nearby wetlands, homes, and residential developments.

This immediate project received $31,866 in supplemental funding.

Tukwila 205 Segale Levee Sinkhole Repair

Another repair occurred on the Green River at the Tukwila 205 Segale Levee, where a sinkhole was discovered on December 11, 2025.

Initial emergency actions stabilized the site, while additional immediate repairs completed later in December and January involved removing unstable material, rebuilding the damaged area with compacted fill, installing geotextile fabric, constructing a crushed surface base course buttress, and repairing damaged infrastructure.

These repairs helped restore the integrity of the levee and ensure it remained ready to perform during future flood events.

This immediate project received $57,956 in supplemental funding.

Investing in Resilience

The December 2025 flood demonstrated both the importance of King County’s flood risk reduction infrastructure and the need to act quickly when facilities are damaged. By funding these immediate repair projects, the King County Flood Control District enabled King County to restore critical flood risk reduction facilities before additional flooding occurred later in the flood season.

These repairs are part of a larger recovery effort that continues to strengthen the County’s resilience to future flood events while protecting communities, infrastructure, salmon habitat, and the natural environment.

Be sure to return for the next installment in this series, where we will highlight immediate repair projects funded on the White River and explain how these investments helped restore critical flood protection facilities following the historic December 2025 flood.