Politics
Each one of these giant fans has a 475 horsepower motor. With eight of them, the state can push 1.2 million cubic feet of air per minute. They hope to never use them.
Enlarge Icon
Each one of these giant fans has a 475 horsepower motor. With eight of them, the state can push 1.2 million cubic feet of air per minute. They hope to never use them.
Credit: KUOW/ CASEY MARTIN

Here's why it's safe to drive through the new tunnel

At a press tour Wednesday the state Department of Transportation showed off some safety precautions in the new tunnel set to open Monday.

In case of emergency:

  • There are 32 emergency exits; 16 on both directions of traffic that are protected from any smoke that could accumulate in the tunnel.


  • Cell phone and FM radio service is available


  • WSDOT's incident response teams will be posted on either end of the tunnel during the daily commutes


  • There are over 300 cameras monitoring 24/7. These are only accessible to transportation and law enforcement officials, not the public.
There are 32 emergency exits in the tunnel and 160 emergency phones that direct to 911.
Enlarge Icon
There are 32 emergency exits in the tunnel and 160 emergency phones that direct to 911.
Credit: KUOW PHOTO/ CASEY MARTIN

Fire suppression:

  • The tunnel has 21 miles of sprinkler pipes to cover less than 2 miles of road.


  • No flammable liquids (like tanker trucks) are allowed in the tunnel.


  • Heat detection will pinpoint where a fire is if one breaks out.


  • At a recent safety drill, WSDOT's Chris Johnson said the Seattle Fire Department was unable to overwhelm the tunnel's ventilation system.
Two of the four sprinkler pumps at the north end of the Highway 99 tunnel. There are 21 miles of sprinkler pipes for the less than 2 mile tunnel.
Enlarge Icon
Two of the four sprinkler pumps at the north end of the Highway 99 tunnel. There are 21 miles of sprinkler pipes for the less than 2 mile tunnel.
Credit: KUOW PHOTO/ CASEY MARTIN

Ventilation and lighting

Chris Johnson, Maintenance and Operations Manager at WSDOT, said cars driving from the south create a current that clears exhaust.

"If the air starts to get a little bit bad," Johnson said, "then the jet fans will fire up and we can artificially create that draft, or that draw, through the tunnel."

The air quality is monitored constantly for oxygen and carbon monoxide levels and large vents on the wall open if need be.

Huge jet fans are on standby in case of a serious incident; Johnson says he hopes they never have to use them.

At both ends of the tunnel bright lights have been installed to help your eyes adjust between tunnel light and sunlight.


What work still has to be done?

"We're pretty much done," Johnson said. "Let's cut a ribbon, let's get a tunnel open. Kind of like a new baby in the family. This is going to be fun."

Enlarge Icon
Credit: KUOW PHOTO/ CASEY MARTIN