An update on the I-17 bridges in Munds Park

The northbound bridge is complete. Work on the southbound
bridge (visible in this photo just behind the new bridge)
will begin in the spring.

Last week we received a blog comment requesting an update on the I-17 bridges that span over Pinewood Boulevard in Munds Park. We thought it was a great suggestion and figured a blog post was in order!

But, first a little refresher …

You might remember we blogged about the bridges back in May. That’s when the first phase of construction was in full-swing and crews were working on the northbound bridge.

We told you then that this project is going to update the bridges initially built in 1958 … back when there wasn’t much development in the area. When the job is finished this fall, there will be two new bridges that will be long enough to accommodate today’s traffic levels and wide enough for a future third lane in each direction on I-17. The project also includes a new sidewalk on Pinewood Boulevard that will allow pedestrians to cross safely underneath I-17.

Where we’re at today

I-17 traffic over the new bridge. 

The northbound bridge is complete and the project is in winter shutdown except for some electrical work being done.

Work on the southbound bridge will begin when the weather warms sufficiently in the spring.

When construction resumes, the southbound bridge will be demolished, then reconstructed and I-17 will be repaved through the work zone.

While this work is being done, the southbound bridge will be closed and motorists will be detoured over to the northbound lanes of I-17. Visit the project webpage for more details.

Materials testing is important when building a road

This is the Hamburg Wheel Tracker. The Pavement Materials Testing group

uses it to evaluate asphalt mixes and determine whether or not the mix is prone 

to rutting. The machine rolls a wheel several times over a slab of asphalt 

concrete to test the mix. 

Yesterday we told you about ADOT’s Pavement Materials Testing group and how it is responsible for testing aggregate and creating asphalt friction course mix designs.

Today, we’ll fill you in on everything else they do … starting with preliminary engineering evaluations.

These evaluations start long before construction begins on a project. A good, solid foundation is important when you’re building a road so soil samples get tested by ADOT for a number of things…

In the PI lab material is tested for clay (not a great foundation to build upon).

ADOT group tests, evaluates rocks for use in asphalt mix

These course screens help separate rocks by size. 

Placing asphalt friction course on a newly constructed road is sort of like icing a cake (stay with us here).

Not only does it represent the final step of a process, but icing and asphalt concrete can both help make the completed product look just a little more finished.

However it’s all for nothing if you don’t have a good recipe … and unlike icing, the directions for mixing up asphalt friction course can’t be found in a cookbook.

Still with us? Good, because this is where ADOT’s Pavement Materials Testing group comes in. They work to develop and continuously improve the asphalt “recipe” for various projects around the state.

When creating an asphalt friction course mix design for a particular job, the goal is to design it so the finished product is strong and holds up to weather extremes. You also want a road that doesn’t crumble and isn’t too slick.

To get a good recipe some testing has to take place in the kitchen … um, we mean lab.

Building a Freeway: Constructing a temporary bypass

Remember this awesome time-lapse video showing the construction of a temporary bypass at Greenway Road and the Loop 303?

Well, today we’ve got an even more in-depth look at how crews built the new intersection – complete with temporary barriers, fences and traffic signals – in just about 43 hours! (Take a look at the photos below for an amazing before and after aerial glimpse of the new bypass!)

Having this new intersection/bypass in place is pretty critical for the rest of the work being completed on the Loop 303 (the project is in its second phase and stretches from Mountain View Boulevard to Peoria Avenue).

The temporary intersection not only helps motorists avoid the work zone, but the incorporation of an equipment pass-through will assist crews as they haul an estimated 75,000 loads of dirt away from the site to build the Greenway Road overpass.

“We started back in August working on this knowing that getting Greenway and the 303 relocated on the detour was going to set this project in motion,” Loop 303 Project Supervisor Mark Wheeler said.

Check out the video above and you’ll see that it took some real coordination to complete the work in such a short period of time (bonus points if you also see the lunar eclipse at about the 1:42 mark).

For more on everything Loop 303, visit www.valleyfreeways.com/Loop303.

Partnering 101

A recent workshop for the
I-10/Loop 303 traffic interchange project. 

When ADOT builds a freeway, there is an essential step that surprisingly requires absolutely no construction or even heavy lifting.

We’re talking about partnering – the ADOT and construction industry process that allows everyone on the project to get together, set goals and talk about the work ahead.

Partnering not only sets a good course, but as a project progresses, the process leads the way through any conflict and helps the team evaluate and measure progress.

But wait … doesn’t this all sound a little familiar?

Maybe that’s because partnering isn’t a new topic for this blog. To get a general overview of how ADOT utilizes partnering, check out our blog post from May. We also wrote about public partnerships that month.

Today we want to focus specifically on how construction project partnerships get off the ground and how they can set the tone for the many working relationships a big freeway project requires.

ADOT builds projects in partnership with private industry, namely construction contractors, suppliers, engineers and associated industries. In fact, 80 cents of every dollar ADOT spends goes to the private sector. That creates jobs and benefits Arizona's economy.

Transportation Defined: Passive Acoustic Device

Passive Acoustic Device

You've probably never gotten a good look at the Passive Acoustic Devices (PAD) out on the freeways … they're easy to miss.

PADs are small objects that sit near the top of utility poles and are barely visible to drivers below, but they collect a lot of useful data.

PADs use microphones to “listen” to freeway traffic. These sophisticated devices can use that information to determine vehicle speed and density in an area. This information helps feed ADOT speed maps.

Transportation Defined is a series of explanatory blog posts designed to define the things you see on your everyday commute. Let us know if there's something you'd like to see explained ... leave a comment here on the blog or over on our Facebook page!

Work starts on Loop 303/I-10 interchange

For a look at what's ahead for the Loop 303, visit
valleyfreeways.com/Loop303.

If you’ve been following our Building a Freeway series, you should be pretty familiar by now with much of the work that’s happening out on the Loop 303.

But we still have a lot to show you! In fact, there’s a significant part of the project we haven’t even touched on yet...

It’s the Loop 303/I-10 interchange and construction is just getting started.

When the project is complete in 2014, drivers can expect many improvements; including a freeway-to-freeway connection between Loop 303 and I-10 (it will look similar to the Loop 101/I-10 interchange in Tolleson and Avondale for those of you familiar with the West Valley).

Right now we’re in the first of four phases and a lot of the preliminary work being done is designed to help ease the commute for drivers once construction begins on the later phases. For example, new ramp interchanges will be built at Sarival Avenue and Citrus Road. Work on those starts in March, but should be finished this summer and the new interchanges will help motorists maneuver around more upcoming construction.

As the project progresses there are a few important sites you’ll want to check in on regularly …

• For updates and all things Loop 303, visit the project page. 
• For details on how construction will impact you and your commute, check out the closures and restrictions page. 

And, of course, stay tuned to the blog. We’ll continue to share important project information along with explanatory videos and blog posts!

Transportation Defined: CCTV Cameras

CCTV Camera

Maybe you've noticed some of the cameras that are perched high above the roadways ...

These are Closed Circuit Television (CCTV) cameras and are used by ADOT's Traffic Operations Center (TOC) to constantly monitor traffic conditions throughout the state.

Most of these cameras can pan, tilt and zoom from any workstation at the TOC, which allows operators to get a closer look at traffic incidents and determine the appropriate response.

Several television stations have access to ADOT's live CCTV camera feeds to show freeway conditions.

The CCTV camera shown, like most, is installed with an important feature ... a lightning protection rod!

Transportation Defined is a series of explanatory blog posts designed to define the things you see on your everyday commute. Let us know if there's something you'd like to see explained ... leave a comment here on the blog or over on our Facebook page!

Adopt a Highway volunteers are appreciated

Adopt a Highway volunteers never can predict what they’re going to find out on the road…

From discarded cigarettes and fast food wrappers to cake mix and bobble heads (see video above), they have not only seen it all, but they've picked it all up.

We’re thankful for the approximately 1,570 volunteer groups who currently adopt an Arizona highway. It’s hard to believe, but roughly 335 of the groups have been volunteering for more than 10 years and of those, 50 have been with Adopt a Highway for more than 20 years!

Travel demand models help plan for the future

Travel demand models give planners an idea of what future
traffic patterns might look like.

Short of a time machine, travel demand models might just be the next best thing for taking a glimpse at the future of our transportation system.

So, what is a travel demand model?

Technically speaking, travel demand models are planning analysis tools that use statistical, econometric and mathematical algorithms to represent transportation system conditions and predict travel behavior response to those conditions.

Less technically speaking, a travel demand model consists of a series of interlinking computer programs that use statistics and demographic information to forecast current and future transportation system conditions.

That means ADOT can plug in data -- info like how many people live and work in various communities -- and the model will forecast the trips taken by drivers and transit passengers, where they’re going and what roads and transit services are being used. Basically, it gives planners a good idea of what future traffic patterns might look like and traffic’s impact upon air quality. (You might remember we talked before about modeling and predictions related to air quality.)

Transportation defined

What is that? We're going to start identifying and defining
some of the transportation-related objects you see on the road. 

Have you ever spotted something on the highway and wondered, ‘what is that and why is it there?’

If you have, the ADOT Blog is here to help you find the answer!

We’re going to start periodically sharing short blog posts that identify and define some of the transportation-related objects, equipment and machinery you see out there on the road.

To make these posts easy to recognize, they’ll be tagged with a “transportation defined” label. We’ll also be linking back to these definitions in our more comprehensive blog posts to help better explain things.

And, of course we’d like to invite you to tell us if there’s anything you’d like explained. Let us know what transportation-related objects you’re curious about … just leave us a comment here or on our Facebook page!

First definition after the jump …

Construction under way on new Cordes Junction interchange

A new Cordes Junction traffic interchange is being
constructed on I-17. (Photo courtesy of Vastco/Sundt)

Those of you who have ever taken I-17 north or south through our state probably are pretty familiar with the Cordes Junction traffic interchange.

It’s the one that sits right between Flagstaff and Phoenix and serves about 13,000 vehicles a day (that’s in addition to the more than 27,000 vehicles that travel daily on I-17 at the junction of SR 69). It also provides access to Prescott, Arcosanti and surrounding communities, along with gas stations, restaurants and other services for travelers.

Believe it or not, the busy interchange was built nearly 50 years ago – back when traffic volumes were nowhere near what they are today.

It’s time for an update!

ADOT takes a look back at 2011

2011's accomplishments include several projects.

The new year officially is here, but before we dive into 2012 we’re going to take a quick look back.

ADOT’s Public Information/Media Relations team came up with a great list of the state’s major transportation accomplishments from 2011 and we thought we’d share it here on the blog!

From new freeway openings to the approval of ADOT’s Long Range Transportation Plan, here's a look at some of the highlights …

Phoenix Area Freeways:
Loop 303 Opens
ADOT widened major stretches of Phoenix area freeways in 2011 and opened the first new segment of freeway to be built under the Maricopa Association of Government’s 20-year Regional Transportation Plan. Fourteen miles of Loop 303 were opened in May between Interstate 17 and Happy Valley Parkway in Peoria, allowing drivers for the first time to use Loop 303 to make the 39-mile trip between I-17 and I-10.

HOV Lane Additions
Drivers benefited from two accelerated projects to add High Occupancy Vehicle lanes along Loops 101 and 202. The final 30 miles of HOV lanes along Loop 101 between State Route 51 in north Phoenix and I-10 in Tolleson were opened in stages during the year and completed in November. Meanwhile, in the Chandler area, 12 miles of carpool lanes were completed this fall along Loop 202 Santan Freeway between I-10 and Gilbert Road.