New Gila River bridges coming on I-10, but there’s a lesser-known Gila River project already underway on SR 79

Since ADOT outlined ambitious plans earlier this year to widen I-10 between Phoenix and Casa Grande, we’ve been talking a lot about new, wider bridges that will carry the Interstate over the Gila River.

The actual construction will generate even more news coverage, but it turns out there’s already another bridge replacement project underway on the Gila River. We figure it’s time to put the spotlight on that lesser-known bridge that’s taking shape east of I-10 in Florence.

The project began in February where State Route 79 crosses the normally dry riverbed. Crews are now working to construct bridge girders for the new structure and are already 36 percent complete with the $22.1 million project.

The work requires overnight restrictions and delays at times, and that will be the case for two weeks, beginning Monday, July 18.

One benefit to drivers is ADOT developed the replacement project with an innovative plan that keeps both lanes of traffic open on SR 79 during peak hours aside from a few days of lane restrictions toward the end of the project. That’s because crews are constructing the bridge in two halves - one on each side of the existing structure - and will slide the pieces together later on.

If you look at the project photos, you’ll see some new piers are already in place under the existing bridge while also extending out on either side. That extra width is where each new bridge half will be constructed.

Eventually, crews will dismantle the existing structure and then slide the segments into their permanent home. That will require two weekends in which the bridge is restricted to a single lane, and a temporary traffic signal will allow only one direction of traffic to flow at a time. 

Throughout the project, drivers should expect a reduced speed limit and occasional lane restrictions. Also, some overnight vehicles may need to use an alternate route. For safety purposes, pedestrians, bicyclists and offroad vehicles are asked to stay out of the work zone in the riverbed and use an alternate route.

The project in Florence is expected to be complete in 2023, which is when ADOT anticipates work will begin to widen the Gila River bridges on I-10. So if you’re a regular traveler on either highway, be prepared to see some big improvements unfolding for the next few years.