Missing Person Investigation Underway on Lake Washington

Date or release: 08/01/2026
Time or release: 0800 hours

Contact: Acting Chief of Police Jeff Magnan
Phone: 206-291-7757
Email: jeff.magnan@mercergov.org

Mercer Island, Wash. — On July 31, 2026, at approximately 10:40 p.m., the Mercer Island Police Department Marine Patrol responded to a report of a missing person believed to have fallen or entered the water from a recreational vessel on Lake Washington.

According to the preliminary investigation, the vessel and its occupants had been on Lake Washington during the Seafair air show and hydroplane races. As the vessel departed the log boom area between Seattle and Mercer Island, a 19-year-old male reportedly told others on board that he needed to use the restroom. The vessel was underway at the time and may have been traveling at planing speed.

When the vessel reached the east high-rise portion of the Interstate 90 floating bridge and slowed due to the restricted speed zone, the occupants realized the 19-year-old was no longer on board. They conducted their own search for approximately five minutes before calling 911.

Mercer Island Police Marine Patrol officers responded immediately and began searching the area using forward-looking infrared (FLIR), spotlights, and thermal-imaging drones. Assisting agencies included the U.S. Coast Guard, Seattle Police Harbor Patrol, Clyde Hill Police Department's drone unit, Bellevue Fire Department, Eastside Fire & Rescue, and land-based patrol units.

The search area encompasses approximately 10 square miles, including the waters surrounding the Lacey V. Murrow Memorial Bridge (Interstate 90). Due to darkness and operational considerations, the active nighttime search was suspended at approximately 12:30 a.m. on August 1. Search operations are expected to resume during daylight hours.
Investigators have contacted the missing individual's family while continuing efforts to determine whether he may have reached shore or another vessel.

No additional information is being released at this time as the investigation remains active.