Three decades-old bridges in Deschutes County are being replaced as the county leverages state and local funding to address deteriorating infrastructure.

The oldest of the three, the Gribbling Road bridge, crosses the Central Oregon Irrigation District canal off of U.S. Highway 20 about seven miles outside of Bend. It’s a 65-year-old timber and steel structure, and it’s vital for emergency responders in the southeastern part of the county.

Laying new beams and pouring concrete for the new, almost $1 million Gribbling Road bridge is scheduled to be finished in early April while the canal is still dry, said Chris Doty, the county’s road department director.

Another bridge project, the Smith Rock Way bridge, is expected to be under construction from March through June and cost roughly $1.1 million.

The third project, the Hamehook Road bridge, which is estimated to cost $1.8 million, is scheduled to begin construction at the end of this year, Doty said.

Multiple parts of the bridge are beginning to crack.

“They’re showing their wear,” he said.

The Gribbling Road bridge is the only one in Deschutes County with a “poor” rating from the U.S. Department of Transportation’s National Bridge Inventory. That means the bridge is structurally deficient and in need of repair. The county is using state bridge funds to do that.

The Smith Rock Way bridge is in “fair” condition, and the Hamehook Road bridge is in “good” condition, according to the federal agency. But they both see much more vehicle traffic than Gribbling Road, leading to some deterioration.

Gribbling Road bridge in dire condition

An estimated 16% of bridges in Deschutes County are in need of repair. That’s around 24 out of 150 bridges, according to an online database.

Traffic has increased on all three of the bridges since 2020 shortening their lifetimes, according to data from the department.

Bridges are meant to have a lifetime of at least 50 years. At least, that’s what Deschutes County aims for when designing a bridge, Doty said.

“The reality is they could last a lot longer than that,” he added.

While the Gribbling Road bridge is in the most dire condition, it’s far from the oldest in the county.

The county’s oldest bridge, which is located on Sisemore Road above the outflow of the Tumalo Reservoir, is 109 years old. Built in 1914, the Bull Springs Bridge underwent rehabilitative work in 2020, and won’t require anymore at least in the near future.

Uncommon to replace three s at once

Doty said three bridge replacement projects occurring at once is uncommon, but so is securing the funding to do so.

Often, it’s difficult for Deschutes County to compete for funding due to the sheer volume of failing bridges on the west side of the state, Doty said.

“Some counties have more failing bridges than we have bridges,” he said.

But an increase in local funding, a portion of it from the state highway fund, allowed the county to quickly address the most pressing improvements.