Declassified Study: Bomb Strike on Grand Coulee Would Have Decimated Hanford Site

I like history, so much so, I spend a lot of time online looking for stories to read and write about. As I was scouring the web for a topic, I ran across a declassified study that was conducted in 1950 that presents the potential effects on the Hanford site after a direct hit of an atomic bomb at Grand Coulee Dam. Although we have come a long way regarding defense and managing rivers in Washington State, and the likelihood of an event of this magnitude seems impossible, I found the report fascinating. And, it gives you an eerie look into our vulnerable past.

What would have happened to the Hanford site after an atomic bomb strike at Grand Coulee Dam in 1950?

According to the 1950 study by Kramer, H. A., this is what could have happened to the Hanford site if the Grand Coulee Dam had been destroyed. The report assumes an atomic bomb or another explosive device would be the cause and explains in detail the effects such a disaster would have on eastern Washington, in particular, the Hanford site – again, the report and data are from 1950.

The study indicated Grand Coulee Dam was vulnerable

The impact of a complete dam breach at Grand Coulee at the time would have filled Lake Roosevelt. And, the river between Grand Coulee and Hanford would increase to a flow of 75,000 C.F.S (cubic feet per second). The impact of the dam’s destruction would have hit Hanford and surrounding areas within 8 to 12 hours and peaked after 27 hours. The city of Richland would’ve been completely isolated and most of the 100 and 300 areas on the Hanford site flooded.

The report has very detailed maximum water level predictions for every area and building on the Hanford site as it was in 1950. It also presents predictions of a partial breach of Grand Coulee. You can read the 19-page report (declassified in 1973) at the UNT Digital Library.