The Morrison Bridge's new deck is worse-off than ever.

Multnomah County, which owns the Morrison, closed down the north-most lane of the bridge at noon today after inspections revealed deep deterioration and cracking to the polymer surface taxpayers spent more than $10 million on just a few years ago.

Temporary closures and spot fixes are nothing new for the deck, but this is: the county says it's not sure when it will even be able to re-open the lane.

"This is going to be closed for some time," says county spokesperson Mike Pullen. "The deterioration is much-advanced, they tell me."

In recent months, officials have scheduled a weekend day to close off the Morrison and examine the polymer panels, which began cracking, shifting, and coming undone nearly as soon as they saw their first auto traffic in 2012. The most recent such closure was in late November, and officials had planned another one in early February. But an inspection earlier this week revealed enough damage to justify immediate closure.

The county now plans to close the bridge for a full inspection on Saturday, from 7 am to as late as 7 pm. When it reopens, there will still be three westbound lanes, since a good amount of that traffic comes off of I-5. Eastbound lanes will be reduced to two.

There's no telling what this new development portends for the Morrison, the city's busiest non-highway bridge. It could be a one-off, or the entire span could start seeing similarly advanced deterioration. As we've reported at length, the county has long known it received at least some flawed material when replacing the Morrison's deck. Engineers decided to use it anyway, when they could have sent it back. An enormous lawsuit currently crawling through the courts system may determine who's at fault.

If you're a frequent Morrison Bridge user, by the way, get used to finding a new route. The county's examining its options for replacing the entire deck again at some point—potentially with the same cracking material.