Issued by the King County Flood Control District on November 20, 2025

This report provides an after-action analysis of two flood events that occurred in King County on November 1 and November 15, 2025. These floods primarily affected the Snoqualmie River Basin, taking the basin into Flood Phase 2 on two occasions. On November 1, 2025, the South Fork Skykomish River also entered Flood Phase 1. For the flood event that occurred on November 15, 2025, the Tolt River and South Fork Skykomish River entered Flood Phase 1.

This report provides a summary, response overview, communications summary, a look at infrastructure and critical facilities, lessons learned, and recognitions.

Flood Event Summary for November 1, 2025

Snoqualmie River Basin

On Saturday, November 1, Flood Phase 1 was initiated at 2:33 a.m. when 6,777 cubic feet per second (cfs) was observed by King County’s “Sum of Snoqualmie River Forks” river flow data chart. The Phase 1 threshold is 6,000 cfs.

At 11:57 a.m. on Saturday, November 1, King County Flood Alerts were issued as the Sum of the Snoqualmie River Forks data exceeded 12,000 cfs, triggering a Flood Phase 2 stage. Immediately following the Flood Phase 2 Flood Alert, King County activated the Flood Warning Center at 12:00 p.m. and issued a public notification to the media around 12:30 p.m. The Flood Warning Center remained open until 9:00 p.m. on Saturday, November 1.

The peak flow of 17,400 cfs for this flood event on the Snoqualmie River was observed on November 2 at 12:00 a.m. at the United States Geological Survey (USGS) gage located on the Snoqualmie River near Carnation.

South Fork Skykomish River

Flood Phase 1 was observed on the South Fork Skykomish River at 1:04 p.m. on Saturday, November 1, as measured by the USGS gage located on the South Fork Skykomish River near Skykomish. The Phase 1 threshold is 6,000 cfs. A peak flow of 8,910 cfs was reached at 4:00 p.m. on Saturday, November 1.

Response Overview for November 1, 2025

This section lists some of the actions taken by the King County Flood Control District and its governmental partners. It is not intended to be an all-inclusive list of governmental actions taken during this flood event.

• November 1: King County opened the Flood Warning Center at 12:00 p.m. to monitor flooding along the Snoqualmie River.
• November 1: The King County Flood Warning Center closed at 9:00 p.m.

Communications Summary for November 1, 2025

This section lists some of the communications provided by the King County Flood Control District and its governmental partners. It is not intended to be an all-inclusive list of governmental communications provided during this flood event.

• October 30 at 2:54 p.m.: King County provided an email update to the King County Flood Control District indicating the National Weather Service (NWS) issued a hydrologic outlook for portions of western Washington, including King County. The NWS forecasts showed the Snoqualmie River reaching Phase 2 on the morning of Saturday, November 1, and no other rivers were expected to reach a flood phase.
• October 30 at 4:16 p.m.: Michelle Clark, Executive Director of the King County Flood Control District, provided an email update to the Board of Supervisors and an extended group of staff members. The Chair and Vice Chair were also contacted by text.
• October 31 at 9:46 a.m.: King County Flood Control District posted a flood update on Facebook.
• October 31 at 9:48 a.m.: King County Flood Control District posted a flood update on X.
• October 31 at 9:50 a.m.: King County Flood Control District posted a flood update on Bluesky.
• November 1 at 2:33 a.m.: Flood Warning System email sent from King County about the Snoqualmie River Basin indicating phase direction is moving upward, and Phase 1 flow is 6,777 cfs based on the King County Sum of Snoqualmie River Forks.
• November 1 at 11:57 a.m.: Flood Alert System phone call and email sent by King County indicating the Snoqualmie River has reached Flood Phase 2, and minor flooding is expected in low lying areas.
• November 1 at 12:14 p.m.: Michelle Clark, Executive Director of the King County Flood Control District, provided an email update to the Board of Supervisors and an extended group of staff members. The Chair and Vice Chair were also contacted by text.
• November 1 at 12:32 p.m.: King County provided an email update to the King County Flood Control District indicating area media outlets will be informed of the Flood Phase 2 and opening of the Flood Warning Center.
• November 1 at ~12:33 p.m.: King County provided an email update to area media outlets.
• November 1 at 12:37 p.m.: Flood Warning System email sent from King County about the Snoqualmie River Basin indicating phase direction is moving upward, and Phase 2 flow is 13,540 cfs based on the King County Sum of Snoqualmie River Forks.
• November 1 at 1:08 p.m.: Flood Warning System email sent from King County about the South Fork Skykomish River indicating phase direction is moving upward, and Phase 1 flow is 6,280 cfs based on the USGS gage on the South Fork Skykomish River at Skykomish.
• November 1 at 1:17 p.m.: King County provided an email update to the King County Flood Control District.
• November 1 at 2:51 p.m.: Michelle Clark, Executive Director of the King County Flood Control District, provided an email update to the Board of Supervisors and an extended group of staff members. The Chair and Vice Chair were also contacted by text.
• November 1 at 9:44 p.m.: King County provided an email update to the King County Flood Control District indicating the Flood Warning Center was closed.
• November 1 at ~12:45 p.m.: King County provided an email update to area media outlets.
• November 1 at 10:25 p.m.: Michelle Clark, Executive Director of the King County Flood Control District, provided an email update to the Board of Supervisors and an extended group of staff members. The Chair and Vice Chair were also contacted by text.

Infrastructure and Critical Facilities for November 1, 2025

This section assesses the impact of flooding on critical infrastructure such as roads, bridges, utilities, and public facilities, and it highlights past investments which may have mitigated the impact of this flood event. It is not intended to be an all-inclusive list of flooding impacts, nor does it highlight all past government investment in area flood mitigation infrastructure.

The following roads were at risk for closure during this flood event:

• Neal Road Southeast
• Reinig Road
• West Snoqualmie River Road Northeast (Walker Road)
• Snoqualmie Meadowbrook Road
• Mill Pond Road

The following images are associated with areas where river facilities exist. You can learn more about locations of river facilities, floodplains, and other important flood related information by using King County’s iMap.

A river facility refers to any man-made or engineered structure that interacts with a river system, with the purpose of influencing or controlling water flow, particularly to reduce flood risks. These include levees and revetments. A levee is a natural or artificial river embankment that prevents flooding, and a revetment is a passive structure that protects against erosion caused by river currents and high flows.

Shake Mill Left Bank Revetment on the left river bank of the North Fork Snoqualmie River. A project was completed here in 2019.

Reinig Road Revetment on the right river bank of the Snoqualmie River. A project was completed here in 2021.

Record Office Revetment on the left bank of the Snoqualmie River. A project was completed here in 2021.

Snoqualmie Falls

Snoqualmie River looking upstream from the pedestrian bridge at Tolt-MacDolald Park & Campground. On the right of the image below is the Welcome Revetment (on the left bank) and on the left of the image below is the Tolt Park Revetment (on the right bank).

Snoqualmie River looking downstream from the pedestrian bridge at Tolt-MacDolald Park & Campground. On the right of the image below is the McDonald Park Revetment (on the right bank).

Stossel Bridge Right Bank Revetment on the right river bank of the Snoqualmie River. A project is expected to go into construction at this location in 2026.

Sinnema Quaale Upper Revetment on the right river bank of the Snoqualmie River. A project was completed at this location in 2016.

Dutchman Road Revetment on the left river bank of the Snoqualmie River. A project is being designed at this location and anticipated to go into construction in 2027.

Flood Event Summary for November 15, 2025

Snoqualmie River Basin and Tolt River

On Friday, November 14, Flood Phase 1 was initiated at 9:33 a.m. on the Snoqualmie River when 6,312 cfs was observed by King County’s “Sum of Snoqualmie River Forks” river flow data chart. The Snoqualmie River Phase 1 threshold is 6,000 cfs and Phase 2 is 12,000 cfs.

On Saturday, November 15, the Tolt River entered Flood Phase 1 at 12:53 a.m. when 2,920 cfs was observed at the USGS Tolt River gage near Carnation. The Tolt River Phase 1 threshold is 2,500 cfs and Phase 2 is 3,500 cfs.

King County activated the Flood Warning Center at 3:15 a.m. on Saturday, November 15. Flood Phase 2 Flood Alerts were issued at 3:16 a.m. for the Snoqualmie River and at 3:30 a.m. for the Tolt River. Around 4:20 a.m., King County issued a public notification to the media. The Flood Warning Center remained open until 12:00 p.m. on Saturday, November 15.

On the Snoqualmie River, the peak flow of 17,800 cfs for this flood event was observed on November 15 at 2:30 p.m. at the USGS gage located on the Snoqualmie River near Carnation. The peak flow of 3,610 cfs on the Tolt River for this flood event was observed on November 15 at 3:15 a.m. at the USGS gage located on the Snoqualmie River near Carnation.

South Fork Skykomish River

On Friday, November 14 and Saturday, November 15, the South Fork Skykomish River entered Flood Phase 1 multiple times as the river level oscillated as impacted by on-again, off-again rainfall. The first Flood Phase 1 was observed on Friday, November 14 at 2:03 p.m., as measured by the USGS gage located on the South Fork Skykomish River near Skykomish. The second occurrence of the South Fork Skykomish River entering Flood Phase 1 happened on Friday, November 14 at 2:42 p.m. On Saturday, November 15, Flood Phase 1 was observed at 12:53 a.m., 1:33 a.m., 2:03 a.m., 2:43 a.m., 3:33 a.m., and 8:03 a.m.

The Phase 1 threshold for the South Fork Skykomish River is 6,000 cfs. A peak flow of 6,220 cfs was reached at 6:15 a.m. on Saturday, November 15.

Response Overview for November 15, 2025

This section lists some of the actions taken by the King County Flood Control District and its governmental partners. It is not intended to be an all-inclusive list of governmental actions taken during this flood event.

• November 15: King County opened the Flood Warning Center at 3:15 a.m. to monitor flooding along the Snoqualmie and Tolt rivers.
• November 15: The King County Flood Warning Center closed at 12:00 p.m.

Communications Summary for November 15, 2025

This section lists some of the communications provided by the King County Flood Control District and its governmental partners. It is not intended to be an all-inclusive list of governmental communications provided during this flood event.

• November 14 at 9:33 a.m.: Flood Warning System email sent from King County about the Snoqualmie River Basin indicating phase direction is moving upward, and Phase 1 flow is 6,312 cfs based on the King County Sum of Snoqualmie River Forks.
• November 14 at 10:56 a.m.: King County Flood Control District posted a flood update on Facebook.
• November 14 at 10:59 a.m.: King County Flood Control District posted a flood update on X.
• November 14 at 11:07 a.m.: King County Flood Control District posted a flood update on Bluesky.
• November 14 at 2:03 p.m.: Flood Warning System email sent from King County about the South Fork Skykomish River indicating phase direction is moving upward, and Phase 1 flow is 6,070 cfs based on the USGS gage on the South Fork Skykomish River at Skykomish.
• November 14 at 2:21 p.m.: Michelle Clark, Executive Director of the King County Flood Control District, emailed King County regarding the Flood Warning website predicting the Snoqualmie River Sum of the Forks crossing the Flood Phase 2 threshold later in the day, and reconfirming that the Flood Warning Center will open if any river hits Flood Phase 2.
• November 14 at 2:43 p.m.: Flood Warning System email sent from King County about the South Fork Skykomish River indicating phase direction is moving upward, and Phase 1 flow is 6,090 cfs based on the USGS gage on the South Fork Skykomish River at Skykomish.
• November 14 at 2:50 p.m.: Michelle Clark, Executive Director of the King County Flood Control District, provided an email update to the Board of Supervisors and an extended group of staff members. The Chair and Vice Chair were also contacted by text.
• November 14 at 4:00 p.m.: King County replied to the King County Flood Control District affirming that the Flood Warning Center will open if any river reaches Flood Phase 2, and that is not anticipated for the remainder of the day as the Snoqualmie River flow was receding for the Sum of the Forks measurement. King County confirmed they will continue monitoring the situation overnight.
• November 15 at 12:53 a.m.: Flood Warning System email sent from King County about the Tolt River indicating phase direction is moving upward, and Phase 1 flow is 2,920 cfs based on the USGS gage on the Tolt River near Carnation.
• November 15 at 12:53 p.m.: Flood Warning System email sent from King County about the South Fork Skykomish River indicating phase direction is moving upward, and Phase 1 flow is 6,090 cfs based on the USGS gage on the South Fork Skykomish River at Skykomish.
• November 15 at 1:33 a.m.: Flood Warning System email sent from King County about the South Fork Skykomish River indicating phase direction is moving upward, and Phase 1 flow is 6,140 cfs based on the USGS gage on the South Fork Skykomish River at Skykomish.
• November 15 at 2:03 a.m.: Flood Warning System email sent from King County about the South Fork Skykomish River indicating phase direction is moving upward, and Phase 1 flow is 6,030 cfs based on the USGS gage on the South Fork Skykomish River at Skykomish.
• November 15 at 2:33 a.m.: Flood Warning System email sent from King County about the Snoqualmie River Basin indicating phase direction is moving upward, and Phase 2 flow is 12,010 cfs based on the King County Sum of Snoqualmie River Forks.
• November 15 at 2:43 a.m.: Flood Warning System email sent from King County about the South Fork Skykomish River indicating phase direction is moving upward, and Phase 1 flow is 6,030 cfs based on the USGS gage on the South Fork Skykomish River at Skykomish.
• November 15 at 3:16 a.m.: Flood Alert System phone call and email sent by King County indicating the Snoqualmie River has reached Flood Phase 2, and minor flooding is expected in low lying areas.
• November 15 at 3:30 a.m.: Flood Alert System phone call and email sent by King County indicating the Tolt River has reached Flood Phase 2, and minor flooding may occur.
• November 15 at 3:33 a.m.: Flood Warning System email sent from King County about the Tolt River indicating phase direction is moving upward, and Phase 2 flow is 3,610 cfs based on the USGS gage on the Tolt River near Carnation.
• November 15 at 3:33 a.m.: Flood Warning System email sent from King County about the South Fork Skykomish River indicating phase direction is moving upward, and Phase 1 flow is 6,090 cfs based on the USGS gage on the South Fork Skykomish River at Skykomish.
• November 15 at 3:53 a.m.: King County provided an email update to the King County Flood Control District indicating the Snoqualmie and Tolt rivers were both in Flood Phase 2 and the Flood Warning Center was activated at 3:15 a.m. Additionally, there were no National Weather Service flood warnings, watches, or advisories in effect, and rainfall rates will taper off later in the morning.
• November 15 at 4:20 a.m.: King County provided an email update to the King County Flood Control District indicating area media outlets will be informed of the Flood Phase 2 and opening of the Flood Warning Center.
• November 15 at ~4:20 a.m.: King County provided an email update to area media outlets.
• November 15 at 8:03 a.m.: Flood Warning System email sent from King County about the South Fork Skykomish River indicating phase direction is moving upward, and Phase 1 flow is 6,050 cfs based on the USGS gage on the South Fork Skykomish River at Skykomish.
• November 15 at 8:58 a.m.: King County Flood Control District posted a flood update on Facebook.
• November 15 at 8:59 a.m.: King County Flood Control District posted a flood update on X.
• November 15 at 9:00 a.m.: King County Flood Control District posted a flood update on Bluesky.
• November 15 at 9:34 a.m.: Michelle Clark, Executive Director of the King County Flood Control District, provided an email update to the Board of Supervisors and an extended group of staff members. The Chair and Vice Chair were also contacted by text.
• November 15 at 11:48 a.m.: King County provided an email update to the King County Flood Control District indicating the Flood Warning Center was going to close at noon.
• November 15 at 12:26 p.m.: King County provided an email update to the King County Flood Control District indicating area media outlets will be informed the Flood Warning Center is closed.
• November 15 at ~12:30 p.m.: King County provided an email update to area media outlets.
• November 15 at 3:08 p.m.: Michelle Clark, Executive Director of the King County Flood Control District, provided an email update to the Board of Supervisors and an extended group of staff members. The Chair and Vice Chair were also contacted by text.

Infrastructure and Critical Facilities for November 15, 2025

This section assesses the impact of flooding on critical infrastructure such as roads, bridges, utilities, and public facilities, and it highlights past investments which may have mitigated the impact of this flood event. It is not intended to be an all-inclusive list of flooding impacts, nor does it highlight all past government investment in area flood mitigation infrastructure.

The following roads were at risk for closure during this flood event:

• Neal Road Southeast
• Reinig Road
• West Snoqualmie River Road Northeast (Walker Road)
• Snoqualmie Meadowbrook Road
• Mill Pond Road

Lessons Learned From Both November 1 and November 15, 2025 Flood Events

This section lists some of the lessons learned by the King County Flood Control District and its governmental partners. It is not intended to be an all-inclusive list of governmental lessons learned during this flood event.

• Flood forecasting and warning appeared to function as designed given there was no loss of life in King County during this flood event.
• Existing flood risk reduction infrastructure appeared to function as designed given flooding impacts were minimal.
• Media outreach and coverage appeared to function as intended to help keep the public properly informed and minimize public risks.
• Flooding, while minor, underscores the policy position supporting the need for further investment in flood mitigation planning and projects.

Recognitions

The King County Flood Control District (KCFCD) was created to provide funding and policy oversight for flood risk reduction capital projects and programs in King County. The KCFCD brings a comprehensive approach to flood management and provides funding to improve King County’s aging and inadequate flood protection facilities, including flood control facilities, capital improvement projects, and floodplain management and restoration programs. Funding is also provided for a regional flood warning center and emergency response, flood facility maintenance, public education and outreach, mapping and technical studies, citizen inquiry, and public response.

During flood events, however, it is the KCFCD’s governmental partners at King County and the other urban and rural cities throughout the county who are responsible for emergency services, transportation, public works, housing, and other government services critical for the protection of life and property.

The KCFCD would like to recognize and show appreciation for the dedicated public services provided by those who work at National Weather Service, King County, and at cities throughout the county. These talented professionals work long hours during flood events, occasionally at risk to their own safety, to ensure the best possible outcomes for the citizens of King County.