During the winter months of 1948 Pacific Northwest Mountains received above-average snowfall. Scientists at the University of Washington estimated there was nearly 40% more snowpack than average. An unusual weather pattern had kept temperatures very cold into late May which prevented the snowpack from melting over time – like a normal year. State agencies became very concerned about the risk of flooding – especially if temperatures warmed too quickly, and issued warnings to cities and residents throughout Eastern Washington. Their concern was soon realized as the weather pattern changed bringing heavy rain and warm temperatures heading into Memorial Day weekend of 1948. This caused a massive snowpack runoff which put enormous pressure on the Columbia River and surrounding tributaries – the Columbia reached 8 feet above flood stage in the Portland, Oregon area and caused flooding throughout Eastern Washington.
Flood evacuations began in Tri-Cities on May 27, 1948
The impact of the rainfall, warmer temperatures, and rising water levels spread quickly downstream causing flooding throughout the Tri-Cities from May 27 through May 31, 1948. Kennewick was impacted most because of its lower elevation. Still, the Richland Wye near Bateman Island and parts of the city of Richland flooded. Those working at the Hanford site struggled to make it work after highways were closed. Approximately 1000 residents were forced from their homes.
This Oregon city was completely wiped out within Hours
In 1942, the city of Vanport, Oregon (near Portland) was built on lowlands (15 feet below the water level of the Columbia River) during the war.
The warm temperatures along with the heavy rainfall created the highest water levels on the Columbia River since the great flood of 1894. And, in the early hours of May 30, 1948 authorities sent a radio alert to Vanport residents, “remember, dikes are safe at present. You will be warned if necessary. You will have time to leave. Don’t get excited.”
Later that day, at 4:05 p.m. a 10-foot wall of water gushed into the city and completely flooded the town, killing 15 people and leaving over 17,000 people homeless. The city, which was only six years old, was completely destroyed and never rebuilt. The area is now home to the Portland International Speedway and Delta Park.
Could this scenario happen again?
After the Vanport incident, the National Guard was deployed to assist residents and President Truman even made a visit to witness the impact the disaster had on the area. In 1950, Congress passed the Flood Control Act of 1950 which resulted in the addition of the Priest Rapids Dam and the Libby Dam in Montana.
See The Damage in Florida from Hurricane Ian
SEE INSIDE Abandoned Battery Russell at Fort Stevens