ARLINGTON—Sunday marks the 12th anniversary of the Oso mudslide that devastated a rural community twelve years ago, with the death of 43 people and a test of Washingtonian strength and remarkable resilience.
The landslide struck the Steelhead Haven neighborhood around 10:37 a.m. near Oso on March 22, 2014. A massive hillside collapse sent mud and debris racing across the North Fork of the Stillaguamish River, destroying 49 homes and leaving the area buried under tons of earth in the deadliest landslide in U.S. history.
Debris covered an area 1,500 feet long with deposits as deep as 30 to 70 feet in some places and a total volume of approximately 270 million cubic feet. The slide also created a barrier lake by damming the river, raising concerns about flooding downstream.
Geologists determined the landslide reactivated an older slide area shaped by ancient glacial activity. Heavy rains in the preceding weeks saturated the soils, leading to liquefaction that allowed the debris to flow with exceptional speed and distance, according to studies by the U.S. Geological Survey.
More than 900 people, including volunteers and neighbors, joined the search and rescue operation under difficult conditions of rain and unstable mud. Eleven survivors were rescued in the initial hours, but the recovery effort lasted until July 22, 2014, when the last victim was found.
The victims included people from all walks of life, from young children to retirees, many with deep ties to the river valley.
Dayn Brunner, whose sister died in the slide, recalled his personal search at last year’s 10th anniversary memorial service at the Oso Slide Memorial.
“It was probably the toughest thing I ever had to do as a son, and as a big brother,” he said. “But I made a promise to my mom that I would dig her out and bring her home so she could hold her one last time, so that’s what I did.”
Another family member, Tom Pszonka, who lost his daughter, son-in-law and two grandsons, spoke of the slide’s broader impact. “The reach of this slide goes beyond 43 souls lost,” he said. “Family members, extended family members, people who worked there. It goes all over the world.”
Another family member, Tom Pszonka, who lost his daughter, son-in-law and two grandsons, spoke of the slide’s broader impact.
“The reach of this slide goes beyond 43 souls lost,” he said. “Family members, extended family members, people who worked there. It goes all over the world.”
The remembrance last year featured the dedication of the Oso Slide Memorial at the Miller Shingle Trailhead in Arlington. The $6 million site provides a permanent space for reflection, with features that tell the stories of victims, survivors and the response effort.
The community embraced Oso Strong, and Oso Strong became their guide through grief and recovery. Today the memorial serves as a testament to that spirit, offering a place for healing.
Author: Mario Lotmore
