Arizona DOT to Update Traffic Signals on Pima County's Ill-Timed Oracle Road

Crews are set to start installing new signal cabinets and controllers to replace the aging equipment now in place.

by Murphy Woodhouse, The Arizona Daily Star, Tucson / May 30, 2017

(TNS) -- The Road Runner is no doubt not the only one to notice that frequent red lights are a part of the Oracle Road experience in Arizona.

That contrasts sharply with some other local corridors, where the lights are timed so well you could almost put your car in cruise control for long stretches.

“That corridor we know has been pretty problematic, it’s often overloaded and there are not a lot of good alternatives for access up into the northwest,” said Paul Casertano, transportation program manager at the Pima Association of Governments. “Both the public and traffic engineers alike recognize that there are some deficiencies in its operation.”

But things are about to change on Oracle, which serves as a key connection between Tucson and Oro Valley. This week, crews are set to start installing new signal cabinets and controllers to replace the aging equipment now in place and re-phase and retime intersections, eventually including all signalized crossings between River and Tangerine roads. The Arizona Department of Transportation, which manages Arizona 77, says the improvements “will provide better traffic flow through the corridor.”

By the fall, the situation is likely to improve even more when ADOT networks the traffic signal boxes, so that they can be controlled remotely and centrally by engineers. As it stands, timing changes have to be done manually, making real-time, on-the-fly signal timing modifications all but impossible.

“Whatever the issue is, whatever adjustments we need to make, we can make them remotely, we can make them at that moment,” ADOT spokesman Tom Herrmann said of the technology, which is being installed at only one other site in the state — Arizona 69 outside Prescott.

Though the corridor is controlled by ADOT, equipment costs for the project — roughly $298,000 — will be covered by the Regional Transportation Authority, though ADOT personnel will oversee installation, according to a 2014 RTA document.

“What we like to say, the public doesn’t really care who owns the signals, they don’t really care who owns the roadway, they just want it to operate better,” Casertano said of the reason the RTA stepped in to pay.

To evaluate the effectiveness of the technology, a before-and-after traffic movement study using Bluetooth technology and paid drivers is already underway. ADOT declined to provide the “before” data until the after all data is collected, but Herrmann said the agency is “very confident ... it will work very well.”


Work on the above-mentioned signal project will begin Tuesday evening between Rudasill Road and La Reserve Drive. Working in overnight shifts from 10 p.m. to 5 a.m. Tuesday through Thursday over the summer, crews will have to disconnect signals as they progress. Law enforcement will be on-site to direct motorists.

A city contractor will start work on a Pima Road improvement project on Tuesday, with electrical work scheduled at the roadways intersections with Dodge and Columbus boulevards.

The first stage is expected to be complete by June 16, and weekday shifts will last from 6 a.m. to 4 p.m. Travel restrictions will be in place.

©2017 The Arizona Daily Star (Tucson, Ariz.) Distributed by Tribune Content Agency, LLC.

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