By Tom Herrmann / ADOT Communications

What do you do with an old freeway when you’ve just built a new one?

In Pinal County, where we’re in the process of building new lanes of Interstate 10 near Eloy, the answer is an unexpected one: Recycle it.

Most of the time, freeway lanes are elevated slightly above the land on either side. That helps drain water when it rains, for example. Creating that elevation usually requires engineers to find additional dirt nearby, often from a borrow pit – nearby ground where removing the dirt won’t cause any environmental or economic problems.

But taking tons of dirt from one place and hauling it to another, sometimes over considerable distances, can be costly.

Now that both westbound and eastbound traffic has moved to the new lanes there’s no need for the old lanes. Arizona Department of Transportation engineers found a way to put the dirt, asphalt and concrete to a better use.

Almost as soon as westbound traffic started using the new lanes in December, we began removing the old lanes. By the time we’re done, we will have moved 16 lane-miles of freeway – 1 million square feet of asphalt, 30,000 feet of guardrail and tons of earth – to form the foundation of the new eastbound lanes.

The savings are considerable. The new I-10 lanes are only about 100 yards east of the old lanes, reducing the time and cost of moving materials from a distance borrow pit. The old guardrails that are in good condition will be saved and used in repair projects around Arizona.

Among the many recycling programs around Arizona, not one includes old freeways as a recyclable item. Not to worry. By putting old I-10 to use in building new I-10 in Pinal County, we’re doing our part.

By Tom Herrmann / ADOT Communications

On most road-building projects, there’s a lot of work you don’t see. From building foundations for new travel lanes to pouring concrete deep into the ground to support bridges, the progress isn’t always visible to drivers passing by.

As you can see in the video above, that’s been anything but the case on the project widening 4 miles of I-10 between Eloy and Picacho. Over the past six weeks, here’s what has happened:

• Westbound traffic moved to the new westbound lanes in early December.
• Crews removed the pavement, bridges and guardrails from the old westbound lanes.
• Eastbound traffic has been moved to new pavement that eventually will be used for westbound traffic, separated from westbound traffic by concrete barrier.
• The new overpass connecting I-10 with State Route 87 has opened, including both westbound ramps and a temporary eastbound ramp.
• SR 87 has opened north of I-10, allowing traffic to connect from the freeway to central Arizona.

Next up: Removing the old eastbound lanes, finishing construction of the new eastbound lanes and implementing the innovation dust detection system designed to give drivers information to make them safe in a dust storm. We're also recycling asphalt and other materials to create the base for the new eastbound lanes.

It's all scheduled to be done by early fall.

By Steve Elliott / ADOT Communications

When it comes to the art of transportation, few things are as striking as a bridge deck pour. In the video above and the photos below, a crew works through the night to put down concrete for the deck of an expanded I-10 interchange with Jimmie Kerr Boulevard in Casa Grande.

You'll even see a Bid-Well, the concrete-smoothing machine we told you about last week.

This effort is interesting beyond the wow factor, as it's a major step forward for a project widening 4 miles of I-10 to three lanes between Earley Road and Interstate 8.

Late next year, when ADOT completes this project and another underway between Eloy and Picacho, I-10 will be three lanes all the way between Tucson and State Route 387 near Casa Grande.

A steady stream of traffic on the new WB lanes of I-10 at Picacho. The lanes opened about 3:30 a.m. EB traffic will move to the new lanes in about a month. pic.twitter.com/SaiiaADgPW

— Arizona DOT (@ArizonaDOT) December 6, 2018

By Tom Herrmann / ADOT Communications

Those driving west Thursday morning on Interstate 10, just after Picacho Peak, were the first to experience one of the most significant changes since I-10 arrived in central Arizona more than 50 years ago.

But chances are they were halfway through 4 miles of the newest freeway pavement in Arizona before realizing that anything had changed. The tweet above shows traffic flowing there.

Almost a year to the day since we began clearing and grubbing to make room for a new, wider stretch of I-10, with three lanes in each direction, we’ve opened the new westbound lanes from milepost 213 to milepost 209 near Eloy. Eastbound traffic will move to new pavement about a month from now, separated by concrete barrier while temporarily sharing what eventually will be pavement only for westbound traffic.

Drivers may not notice because there isn't as much as a turn onto the new pavement. In fact, we’ve removed a slight turn to the left for westbound drivers, creating a straight road up to State Route 87. The road will go under a new interchange with SR 87, then veer left to reconnect with the existing westbound lanes.

Once everyone is on the new pavement, we’ll demolish the current lanes of I-10 over that 4-mile segment and use the dirt and cement as a base for the new eastbound lanes. Eastbound drivers will get their own new lanes sometime this spring.

Then we’ll do something that hasn’t been done before: building an innovative system to identify dust storms and give drivers the information they need to make smart, safe decisions when blowing dust makes it hard to see where you’re driving.

Together, more travel lanes and dust detection will make I-10 safer, which is the reason we’re doing all of this in the first place.

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

Quietly, without much fanfare, Arizona Department of Transportation crews are moving traffic on westbound Interstate 10 back to the original bridge over Wilmot Road. No ceremony, no ribbon cutting. Just business as usual, and on to the next project.

For the second time in two summers, we used a temporary bridge that allowed us to make repairs and repave the two I-10 bridges over a major Tucson roadway. Back in May, we slid it into position in the median and created a temporary road connecting the bridge with the I-10 lanes that have been carrying traffic in this part of the city since 1965.

For the first three months, eastbound traffic moved to the left, crossed the temporary span, moved back to the right and continued on toward Benson and beyond. Then it was westbound traffic’s turn to do the same thing.

Drivers hardly noticed. The freeway had two lanes open in each direction almost the entire time. There were just a few restrictions on Wilmot Road below the bridges, and most of those took place at night to avoid inconveniencing too many drivers.

Simple.

But that simple, creative effort to use a temporary bridge saved Tucson area drivers more than they realize. Without the bridge, drivers would have been required to merge into the right lane, exit and then re-enter I-10 and get back up to freeway speed. Delays on I-10 would have been tremendous. Life would have been no better on Wilmot Road, which likely would have been closed with detours for most of the nearly six months it took to repair and repave the bridges.

Instead, there were few delays, few restrictions on Wilmot Road and no additional traffic clogging Craycroft and Kolb roads. The I-10 bridges at Wilmot Road are essentially new bridges without the cost or inconvenience of building new ones.

And a month ahead of schedule, well before the coming holidays, our trucks are back in the maintenance yard and our crews are on the way to their next jobs.

Nice work by the men and women in the orange vests and yellow hard hats.