I-5 bridge
I-5 Bridge collapsed in Washington after an oversize truck struck a structural beam. Two vehicles fell into the river. All three occupants survived. YouTube

An I-5 bridge collapses In Washington after a truck hauling an oversize load struck the top, causing devastating structural damage. The I-5 bridge collapse caused two vehicles to fall into the Skagit River below. Thankfully, the three occupants in the vehicles all survived with only minor injuries.

According to authorities, the I-5 bridge collapse occurred on Thursday at about 7 p.m. Initially, the cause of the bridge collapse wasn't clear clear and civil engineers even wondered whether to bridge gave way on its own. During an overnight news conference, Washington State Patrol Chief John Batiste officially claimed the bridge collapse on a tractor-trailer that carried a tall load, colliding with an upper beam on the span.

"For reasons unknown at this point in time, the semi struck the overhead of the bridge causing the collapse," Chief John Batiste said.

While the tractor-trailer in question managed to cross the bridge before its collapse, two vehicles that followed plummeted 50 feet as the bridge crumbled. The truck driver remained at the scene to cooperate with the authorities.

Dan Sligh and his wife were traveling for a camping trip on Thursday when Dan noticed a big puff of dust as he approached the I-5 bridge in a pickup truck.

"I hit the brakes and we went off," Sligh told reporters from Skagit Valley Hospital. The other man in another vehicle that fell into the river is in stable condition and recovering at United General Hospital. Sligh added that he "saw the water approaching ... you hold on as tight as you can."

"Thanks to the rescuers and a little bit of luck, we had three Skagitonians who made it out of the Skagit River alive," Washington Gov. Jay Inslee said in a statement.

According to Transportation Secretary Lynn Peterson, the bridge was inspected twice last year and the necessary repairs were performed.

"It's an older bridge that needs a lot of work just like a good number of bridges around the state," she said.

In the meantime, transportation officials are working on plans for either a temporary or permanent replacement.

While the bridge wasn't classified as structurally deficient, the Federal Highway Administration database listed the I-5 bridge as "functionally obsolete," which deems its design outdated due to its narrow shoulders and low clearance. The I-5 bridge was built in 1955.