Impact: Interstate 5 Highway Bridge in Mount Vernon Collapses [Video/Photo] image

A large section of an Interstate 5 highway bridge in Mount Vernon, Wash., over the Skagit River collapsed Thursday dropping two vehicles into the water, local authorities said.

There were no fatalities reported at the scene, about 2 hours north of Seattle. It is the longest, busiest freeway in the west because is all way from Mexico border all the way up to Canada.
Rescue crews were able to pull all three people from the semi-submerged vehicles.

“We don’t think anyone else went into the water,” said Marcus Deyerin, a spokesman for the Northwest Washington Incident Management Team.

“At this point we’re optimistic.”

Two of them were reported in stable condition at the Skagit Valley Hospital while a third person was transported at the United General Hospital in Sedro-Woolley, again in stable condition.
According to several witnesses, a truck carrying an oversize load had crossed the bridge and struck it just before the collapse.

“It appears the commercial vehicle made contact with the bridge,” state Trooper Mark Francis said. “Whether it was the cause” of the collapse or made contact as the bridge was falling “that will all come out in the wash. But it appears it hit the bridge.”

Interesting is that it has been some concern over the years about flood damage and rain damage along this stretch, what they call the “three bridge” corridor, a significant pinch point they say in the levee system in this area where flooding over the years could cause some problems. The three bridges in the reach are the Interstate 5 Bridge, the riverside Bridge and the Burlington Northern Santa Fe railroad bridge.

The 1,111-ft. Skagit River Bridge was built in 1955 and is used by almost 71000 vehicles every day according to the National Bridge Inventory Database. It got a 57.4 rating in 2010 – “Bridge foundations determined to be stable for assessed or calculated scour condition”, the National Bridge Inventory saying that the structure is in satisfactory condition, superstructure in fair condition and the substructure in satisfactory condition.

However, according to the American Society of Civil Engineers a bridge that scores under 50 qualifies for replacement. Again in 2010 this got a 57.4 rating.
The statewide average at this moment is 80, according to an Associated Press analysis of federal data.

Alternative routes:
Heading northbound: Highway 538 to Highway 9 to Highway 20 then back to Interstate 5
Heading southbound: Highway 20 to Highway 536 to Interstate 5