One of ADOT’s major priorities while rebuilding the I-10/Houghton Road interchange is to minimize disruptions and closures, which means we’ve got to move really fast when we close a roadway.

If you’ve driven through that interchange in the last couple months, you’ve seen that our crews have moved so quickly that they’ve transformed the landscape on half of the interchange in less than two months. This photo from the project team shows the work so far, including constructing bridge piers for a new overpass on the west side of the interchange, regrading everything on the east side of interchange and building up the earth for new ramps.

That’s a lot of progress for a project that kicked off Aug. 24.

We closed two of the interchange’s ramps in late August, with a goal of rebuilding and reopening them before Thanksgiving. Those ramps – the westbound exit ramp and eastbound on-ramp – are already taking shape and should be paved by early November.

We’ll rebuild the ramps on the west side of the interchange as well, but they will remain open through the project except for an occasional nighttime restriction or closure. Likewise, only occasional overnight restrictions and closures will be needed on Houghton Road. And, I-10 will remain open, though drivers should expect overnight lane restrictions at times.

The new $24.4 million interchange east of downtown Tucson is expected to be complete in late 2021. It will feature southern Arizona’s first diverging diamond interchange – a type of interchange where drivers cross and travel on the left side of the overpass while crossing the interstate.

You can read more about the I-10/Houghton Road project and diverging diamonds here. And if you’ve driven through north Phoenix recently, you may have noticed ADOT opened Arizona’s first major diverging diamond interchange earlier this month at I-17 and Happy Valley Road. The Phoenix interchange won’t be fully complete until late this fall, but the major elements are in place if you’re looking to get a feel for what’s coming to I-10 and Houghton Road in southern Arizona next year.

Since an eastbound Interstate 10 bridge started carrying traffic over Ruthrauff Road in 1965, the number of vehicles that have traveled this northwestern Tucson locale is impossible to calculate.

But once crews began demolishing the structure this week, we can count exactly how much time it took to reduce the bridge’s surface into concrete rubble and twisted rebar: two days.

This Flickr album of the demolition work shows the rapid progress we’re making to rebuild I-10/Ruthrauff Road interchange only two months after starting the $129 million project.

As for the remaining parts of the bridge, they’ll also be history by the end of the week.

If you’re wondering how I-10 traffic can keep flowing with one of two bridges now gone at Ruthrauff Road, here’s the solution ADOT’s project team has in place: Westbound I-10 traffic is now getting through the work zone on the westbound frontage road, while eastbound I-10 traffic has been shifted to the old westbound lanes.

Some temporary sections of pavement allow three lanes of traffic to flow in each direction. And we’re maintaining access to all businesses with other temporary changes to the frontage roads.

The demolition work is just one of many dramatic changes drivers will see until the I-10/Ruthrauff Road project is completed in late 2021. Stay tuned for more photos and other updates.

If your daily commute takes you along Interstate 10 in northwest Tucson, get ready to see some big changes to the freeway's configuration by the end of this weekend.

But that will be nothing compared with the even bigger changes that will transform the highway near Ruthrauff Road in the coming year: A decades-old bridge will soon become rubble. Retaining walls will rise up. And half of a new overpass will emerge at the center of a mile-long work zone.

That’s a lot of change to take in as ADOT begins a major phase of the nearly two-year project to rebuild the Ruthrauff Road/El Camino del Cerro interchange.

And it all starts with traffic restrictions this weekend. Here’s what to expect ...

On Friday and Saturday nights, crews will work overnight to move traffic away from the current eastbound lanes of I-10. That means shifting westbound I-10 to the westbound frontage road, and eastbound I-10 to the existing westbound lanes.

“That gives us the ability to create a pretty large work zone for that western half of the project, while still maintaining three lanes of traffic in each direction through the project area,” said Dan Casmer, ADOT’s senior resident engineer on the Ruthrauff interchange project.

With traffic out of the work zone, crews will start demolishing the existing eastbound I-10 bridge over Ruthrauff Road by the end of the month. After drainage and other underground utility work is complete, crews will rebuild about a one-mile segment of eastbound I-10.

That will be followed by retaining walls and half of the new Ruthrauff/El Camino del Cerro bridge, probably the most visible signs of progress for drivers.

“They’re going to see a lot of work going on and it’s going to move pretty quickly once we give the contractor that big area to work in,” Casmer said. “You’ll see that demolition happen almost immediately.”

For the rest of this year, the traffic shift will place drivers on a mix of existing pavement and some stretches of new asphalt. While much of that pavement will be temporary, crews took care to fill in dips and avoid jarring bumps.

“We’ve done a lot of prep work so it should be a nice smooth ride,” Casmer said.

You can find more information about the I-10/Ruthrauff Road project, including traffic alerts, at azdot.gov/RuthrauffTI.

Work started today on a project that will bring big improvements to the Tucson area by reconstructing the interchange at Interstate 10 and Ruthrauff Road.

As we shared last week, the project will improve traffic flow and safety for drivers, and it’s the third of its kind in the last several years that ADOT has undertaken in conjunction with the Pima Association of Governments.

Just like the rebuilt interchanges at Ina and Prince roads, this modern design will feature an overpass above the Union Pacific Railroad tracks. More than 40 trains a day pass through Tucson, leading to plenty of backups onto the freeway and delays for drivers on Ruthruaff. And like the Ina and Prince projects, we’ll widen I-10 near Ruthrauff Road so the highway can better serve this growing region.

If you use Ruthrauff Road, or El Camino del Cerro just west of I-10, expect periodic lane restrictions for the next several weeks. Construction activity will ramp up by late February or early March, when the Ruthrauff interchange will close.

We’ll maintain access to businesses on the frontage roads throughout the project.

We expect to complete the interchange in late 2021. Get traffic updates, detour information and project details at azdot.gov/RuthrauffTI.

By Tom Herrmann / ADOT Communications

A few minutes might not seem like much, unless you’re running late on a Monday morning and the boss is waiting to greet you. Then the last thing you want to see is a traffic signal ahead.

But if you’re driving south of Oracle Road (State Route 77), headed toward downtown Tucson, that signal just may be the best news of your morning.

ADOT engineers in Tucson have installed Pima County’s first adaptive traffic signals in an 8.5-mile section of Oracle between Tangerine and Rudasil roads. Sensors in the roadway measure the speed and volume of traffic and send the information to a computer that can adjust the length of the signals to improve the flow of traffic – including modifying left turn signals.

Traffic sensor map

The system, funded by ADOT and the Regional Transportation Authority, was installed this summer. So far the results are good news for the estimated 60,000 drivers who use the roadway each day from places like Oro Valley.

Travel times in the area have been reduced by about 10 percent – about two minutes off the morning southbound commute that used to take as long as 20 minutes. We’ve seen a similar improvement for northbound commuters headed home in the afternoons.

A side benefit: Oracle is a safer road during the busiest periods. Traffic signals are timed to match the speed limit during non-peak hours. That means driving the speed limit will get you where you’re going just as fast as the driver who insists on speeding.

From now on, you have a few extra minutes in the morning. Enjoy, thanks to the smartest traffic signals you may ever see.

By Steve Elliott / ADOT Communications

ADOT rest areas are far more than places to – well, you know.

Among other things, rest areas provide opportunities to stretch legs, walk pets, have picnic lunches and safely use phones and other mobile electronic devices.

We understand it's a hardship when a rest area closes for a long renovation, and we appreciate your patience while we upgraded facilities at the I-10 Sacaton Rest Area between Phoenix and Casa Grande.

Located at about 30 miles southeast of Phoenix near State Route 387, Sacaton is the only ADOT pit stop along I-10 between Tucson and Phoenix.

Our video team was on hand as Sacaton reopened last week to show the improvements and talk with travelers. We hope you enjoy the video above as well as the many upgrades at; this well-used rest area.

By Tom Herrmann / ADOT Communications

How did the freeway cross the road?

It sounds too simple. Every time a freeway crosses a major street there’s an interchange. For years, engineers have chosen from two primary designs: a diamond interchange with four on- and off-ramps connecting the freeway with the street, and a cloverleaf that uses a combination of long straight ramps and four circular ramps that look a little like a four-leaf clover.

If only life were that simple.

The options for engineers today are endless. Some of the options are already in use or planned in Arizona. There’s the Single Point Urban Interchange, like the one was just constructed on Interstate 19 and Ajo Way, where all ramps come to a single point and are controlled by a single traffic signal. A diverging diamond design, which is planned for Happy Valley and I-17 in Phoenix, two South Mountain Freeway interchanges and Houghton and I-10 in Tucson, eliminates left turns across traffic by having drivers make a temporary shift to the left side while crossing the freeway.

Ramps themselves can add another twist. For the southbound on-ramp at Ajo Way and I-19, our engineers wanted to make it easier for drivers to merge while getting on or off I-19.

Introducing a braided ramp.

To prevent drivers getting on and off the freeway from having to maneuver around each other, in a braided configuration one ramp is elevated, passing over the other ramp.

At Ajo Way and I-19, the southbound on-ramp will pass over the top of the Irvington Road exit ramp. It looks a little like braided hair. You can see a demonstration of how a braided ramp works in the video above, which was made by the city of Round Rock, Texas.

The drivers never cross paths, enhancing safety.