SACRAMENTO (CBS13) – A crumbling roadway has caused two lanes of northbound Interstate 5 in Sacramento to be closed Thursday morning.

California Highway Patrol says the #4 and #5 lanes are closed due to the crumbling roadway.

A big hole has appeared due to the road crumbling on northbound I-5. (Credit: CHP Valley Division)

A big hole has appeared due to the road crumbling on northbound I-5. (Credit: CHP Valley Division)

Officials say it’s looking like a “long term” closure. A significant traffic impact is expected on traffic through Downtown Sacramento.

Drivers are being urged to avoid using northbound I-5 through Downtown. Alternate routes include Business 80 and Highway 50.

The Richards Boulevard off-ramp is still open, CHP notes.

The root of the problem was exposed by the cavity: a clogged drainage pipe. Caltrans says the pipe was inspected and tested only a week ago. Inspectors are now trying to determine what caused the pipe to back-up.

It isn’t the first time this stretch of freeway has suffered damage from some sort of structural failure. Back in August, a pothole plagued I-5 and damaged about 20 cars.

Caltrans says the crumbling road has nothing to do with the highway itself.