About the Seattle nuclear fallout shelter under I-5, the only one in the US

In November 1962, only a month after the Cuban Missile Crisis, excavation of a shelter in Seattle began.

It was expected to be the first of several fallout shelters across the U.S., but ended up being the only one built in the country.

The May 15, 1962, Seattle Times identified the structure as “the nation’s first fallout shelter to be built into a freeway.”

Designed by the Seattle engineering firm Anderson Bjornstad Kane and built by McDonald Construction of Seattle for $67,300, the shelter is located under southbound Interstate 5, at the north end of the Ravenna Bridge.

Once construction of the shelter began, contractors were given only 120 days to build it.

The shelter was dedicated on March 29, 1963.

“It’s a pretty minimal shelter, and it’s not actually a bomb shelter, it’s a fallout shelter,” Scott Williams of the Washington State Department of Transportation told KIRO-FM Radio in 2018. “So, it wasn’t designed to survive a direct nuclear strike on Seattle.”

The building is about 3,000 square feet, with an 18-inch-thick concrete roof and 15-inch-thick walls.

The main entrance is a sliding, heavy metal grate that leads to an underground concrete hallway to the main part of the facility.

The hallway was designed with many right-angle turns to prevent gamma rays from reaching the interior.

There was a maintenance room with a diesel-powered electric generator, an air circulation system with heat and air conditioning, a well and pipes that connected to the city water and sewer systems.

Other rooms were available to store food or provide simple medical care.

There were two bathrooms with three toilets, a urinal, two sinks and two decontamination showers.

Next to the bathrooms there was a very narrow “escape tunnel” that led out to an area near the street-side entrance.

Walls were painted a pale, institutional green. Freeway noise was audible, but muffled.

Originally designed to hold about 200 people, it was designed with triple-decker bunk beds with single people separated by gender, and families between them.

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The communal living area provided about 9.1 square feet per occupant, just smaller than a yoga mat.

There was no kitchen, stove or refrigerator. An operations manual suggested that people would eat canned food, warmed by “placing it in your armpit and holding it there for 10 or 15 minutes.”

Occupants were only allowed to bring items that would “increase shelter habitability,” medicine and “special health foods.”

All food would be turned over to the shelter manager for equitable distribution.

“In general, survival rather than comfort will be the primary objective,” the 1963 shelter guide said.

Animals and pets were not allowed.

Which Green Lake or Ravenna residents were be sheltered apparently depended on how fast they could reach the shelter’s door.

When the shelter reached maximum capacity, the shelter was supposed to be locked and anyone left outside was supposed to be directed to the next nearest available shelter; however, there weren’t any.

By the late 1970s, the shelter was used as a district records-storage center for WSDOT.

The emergency escape tunnel was blocked and the communications equipment was removed.

“The only one that was ever built is the one here in Washington state,” Williams said. “By the time it got built, I think people realized it wasn’t really a great idea. Nuclear bombs were getting so big (and) with Soviet submarines, the attacks were going to come really quick,” and shelters wouldn’t be much use.

By 2022, the shelter has been completely sealed up with no further access.