San Tan Valley-area drivers who take State Route 79 south should plan for lane restrictions, slower speeds and delays starting July 6, as the Arizona Department of Transportation (ADOT) begins building new passing lanes on an 8-mile stretch of the highway near Florence.

SR 79 is a common route for people driving to and through the San Tan Valley area, so the restrictions are likely to affect local drivers heading toward Florence, Tucson or U.S. 60. The work will continue through summer 2027, meaning more than a year of on-and-off restrictions on that part of the highway.

Where the Work Is Happening

The project covers SR 79 between milepost 140 and milepost 148 in Pinal County — starting about 3 miles north of the Gila River in Florence and running north to about 2 miles south of where SR 79 meets U.S. 60. The work zone is in unincorporated Pinal County, part of the broader San Tan Valley area.

What Drivers Can Expect

During work hours, the speed limit through the project area will drop to 55 mph. ADOT says drivers may run into shoulder closures, lane closures, flagging operations — where a worker directs traffic through the zone — and other restrictions at different points along the route.

Crews will work daily from 6 a.m. to 6 p.m. Monday through Thursday, and from 6 a.m. to noon on Fridays. The schedule can change because of weather or other conditions. ADOT advises drivers to slow down and watch for construction workers and equipment in the work zone.

What Is Being Built

The $6.3 million project is meant to give drivers room to safely pass slower vehicles on what is largely a two-lane highway. The work includes:

• Passing lanes along both directions of the highway — added stretches of road where drivers can move around slower traffic.

• New paved shoulders next to the passing lanes.

• Repairing or replacing pavement where needed.

• Replacing guardrail.

Staying Updated

ADOT will send advance notice of specific closures and restrictions to email subscribers and post them on the project's traffic alert page. Drivers can find project details on ADOT's website under Southeast District, State Route 79 Passing Lane Project: Milepost 140 to 148.