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.
• 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!

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.

I-10 Widening in West Valley

Another significant milestone was marked in August with the completion of ADOT’s three-year initiative to reconstruct and widen I-10 between Loop 101 and Verrado Way. Those projects modernized I-10, transforming what had been a limited highway with two lanes in each direction into a modern freeway that now provides as many as five lanes in each direction – including carpool lanes.

State Highway System:

Mescal Road/J-Six Ranch Road Bridge

Just over six months after a fiery crash damaged the Mescal Road/J-Six Ranch Road bridge, ADOT swiftly rebuilt the bridge to reconnect the Cochise County communities of Mescal and J-Six Ranch, which were separated by I-10 and depend on the overpass for convenient access to goods, services and neighbors. While the bridge was out of service, residents and workers in the Benson-area communities were required to take lengthy detours around I-10 to reach the other side of the highway. Federal Highway Administration emergency relief funds, a shortened time frame for designing the replacement bridge and a quick construction bid process all helped put the project on the fast track. A typical bridge construction project can take up to two years.

State Route 260 Widening

Continuing a decade-long commitment to expand the capacity of SR 260, ADOT completed a project to widen the highway starting 15 miles east of Payson from Little Green Valley to Thompson Draw. The $20 million project is the fourth of six projects to construct a four-lane divided highway from Star Valley to the top of the Mogollon Rim.

State Route 87 Improvements

ADOT fulfilled its commitment to complete SR 87 improvements before the Memorial Day weekend and in time for the busy tourism season in the Rim Country. The $11.8 million reconstruction and widening project included the addition of a third southbound lane to enhance safety and traffic flow along the uphill stretch during drives between Payson and the Phoenix area. The improvements were the latest in a series of projects during the last two decades to enhance travel on SR 87, which is now a divided four-lane highway between Mesa and Payson.

US 93 Widening Project

Shortly after ADOT completed a $71.3 million widening project on the US 93 approach to the new Hoover Dam bypass bridge in 2010, the first Desert Bighorn Sheep were spotted in February using one of the three wildlife crossings that were constructed to protect motorists and provide a safe crossing for the native animals. The project earned ADOT several honors this year, including the Arizona Chapter American Public Works Association Award, 2011 Public Works Project of the Year and FHWA’s 2011 Exemplary Ecosystem Initiative Award for the agency’s creative and innovative solution to balance motorists’ safety, while protecting wildlife and connecting ecosystems.

Hassayampa River Bridge Project

Just in time for the Fourth of July weekend, ADOT completed a $3.9 million bridge project over the Hassayampa River on I-10, approximately 40 miles west of downtown Phoenix. This area is a major route for travelers heading to and from California along I-10.

Overnight Bridge Demolition

On a late April night in southern Arizona, ADOT tore down two bridges in 10 hours – no small task. ADOT had already planned to remove the old Marsh Station bridge, which required a 67-mile overnight detour for motorists on I-10 east of Tucson. About three weeks before the demolition was set to occur, two semi trucks collided under the overpass at the Mescal Road/J-Six Ranch Road bridge. The bridge was badly damaged from the resulting fire and would have to be replaced.

Planning and Programming:

Long Range Transportation Plan

For more than two years, ADOT worked toward developing the state’s Long-Range Transportation Plan, a blueprint that looks 25 years into the future to determine how to plan for and fund transportation projects that keep up with Arizona’s needs. The State Transportation Board formally approved the Long Range Transportation Plan, also known as What Moves You Arizona, in November, allowing ADOT planners to move ahead with their work to develop a transportation system that will carry Arizona into the future. The award-winning program was nationally recognized for planning and involving the public.

Intercity Rail Study

In October, ADOT kicked off the public outreach phase of its intercity rail study. The study’s goal is to identify if there is a need for intercity rail along I-10 between Phoenix and Tucson. Over the course of a month, ADOT gathered information, data and comments. The agency will provide its findings to the public and to policymakers, so they can make an informed decision about how to move forward. ADOT is looking at all options, which include rail, transit—and the option to build nothing at all. The study will be complete in 2013.

Bicycle Safety Action Plan

As part of our public safety plan, ADOT is developing a Bicycle Safety Action Plan to help keep cyclists safe on Arizona’s highways. The goal is to reduce the number of bicycle crashes with motor vehicles and improve safety for both cyclists and drivers.  The goal of the Bicycle Safety Action Plan is to reduce the total number of bicycle crashes on Arizona highways by 12 percent by 2018.

Safe Routes to School

This year, nearly $3.5 million in grant funding was distributed by ADOT for 21 Safe Routes to School projects for schools and communities statewide. Eight of these projects, totaling $2.8 million, were designated for infrastructure improvements, such as the construction of sidewalks, crosswalks, bike lanes, signage and striping. An additional 13 projects, totaling $720,000, went toward non-infrastructure elements, such as providing bike helmets to students, safety education and law enforcement. All Safe Routes to School projects are designed to get kids walking or biking and adopt healthy habits.

Motor Vehicle Division and Enforcement and Compliance Division:

Motor Vehicle Division

MVD continued to improve the quality of customer service at MVD offices by shortening the wait times for the more common motor vehicle and driver license transactions, while serving over 3.5 million customers at MVD’s 54 offices or satellite/specialized offices in 2011 The average wait time per transaction was approximately 19 minutes, compared to over 45 minutes just five years ago. Throughout the year, MVD also provided transaction assistance to returning soldiers with the U.S. Army Intelligence Command at Fort Huachuca in southern Arizona. ADOT also launched several new specialty license plates, including the long-awaited Arizona Centennial plate.

Enforcement and Compliance Division

ADOT officers conducted Operation Bullhead, joint-agency commercial vehicle enforcement operation in Mohave County at the request of Bullhead City officials. ADOT officers recovered stolen vehicles identified during inspections. The enforcement division also created a Single Trip Overweight International Border Permit program for produce transporters out of Mexico and assisted local law enforcement with scrap metal yard investigations.

Other Accomplishments:

Grand Canyon National Park Airport

In June, the Grand Canyon National Park Airport, owned and operated by ADOT, began daily 737 airline service from McCarran International Airport in Las Vegas. Travelers can now book a flight on Vision Airlines out of Las Vegas to the Grand Canyon. The new service is the first step in a larger vision to make it easier for all tourists to visit the canyon. The Transportation Security Administration was also stationed at the airport this year, making it easier for airline companies to fly into the airport, since they no longer have to provide their own passenger screening.

Accommodating existing traffic is a key priority when ADOT builds a freeway …

Depending on the project, that can mean working out a construction schedule that takes rush hours into account or hiring extra crews to flag and direct traffic through the site.

But, on the Loop 303 project in the West Valley drivers will notice a new construction bypass that (amazingly) was built in around 43 hours this past weekend. The bypass will be in place for the next 10 months and not only will it allow for a more efficient way to haul dirt, but it’s also going to help drivers avoid the construction zone!

Building the bypass

Crews shut down the intersection at Greenway Road and the Loop 303 at 10 p.m. Friday, Dec. 9.

Roughly 8,000 cubic yards of dirt was hauled in from other parts of the project site to build up the road. That dirt was placed Friday night in eight-inch layers and was compacted until it was the right height for the bypass (see video above!). After that, the road was paved and striped on Saturday.

Prior to the weekend work, crews had built everything they could up until the point where the bypass would cross “live” traffic and require the closure. That required even more dirt – about 40,000 cubic yards.

Crews not only had to build the bypass, but also installed temporary concrete barriers, fencing, sidewalk and a traffic signal.

The traffic signal went in Saturday morning after the power was shut off to the “old” signal. The signal pole’s electric meter and pedestal were set to the new location and power was turned on. ADOT wired the signal Sunday morning and installed a common video detection device that will help with signal timing.

After some finishing touches, the bypass was ready and opened to traffic by about 5:15 Sunday evening – 12 hours ahead of schedule!

Before you can build a freeway, you’ve got to move a little dirt...

Make that a LOT of dirt, especially in the case of the Loop 303 project under construction right now in the West Valley.

Crews are working to construct additional lanes and plan to move about 3 million cubic yards of dirt by the time the project is finished. (By the way, a lot of work is planned for the Loop 303. The portion of the project we’re talking about runs from Mountain View Boulevard, south to Peoria Avenue.)

That much dirt translates to roughly 200,000 truck loads – and these are some big trucks (take a look at them in action in the video above).

Other projects may, or may not require this much earthwork. It depends on the road design and the original shape of the terrain.

Take the Loop 303 project for example...

Part of the freeway (starting slightly south of Greenway Road headed north) is going to be depressed ... in other words, freeway traffic will pass underneath the nearby local streets. The rest of the freeway (heading south of Greenway down to Cactus Road) is going to be elevated and will pass over local traffic.

So, parts of this project need to be dug out and other portions need to be lifted up. The dirt that crews dig out in some areas helps to build the overpasses in other spots.

If you’re lucky, it all balances out. Otherwise, purchasing additional dirt is an option. Or, if there is a surplus, the extra dirt often can be utilized in landscaping and to build berms.

Moving the dirt...

Before any digging can start, the dirt is pre-wet to make it easier to move and help with compaction and dust control.

After that, there’s some heavy-duty equipment that comes into play.

Typically, an excavator is used to dig up the dirt. The excavators being used on the 303 project have buckets that hold about seven cubic yards worth of material at a time. Those load onto something called a belly dump truck (see photo below).

Scrapers also are used to dig up the dirt. Depending on their size, scrapers can hold and transport about 14-18 cubic yards at a time.

Contractors have geotechnical reports that tell them the type of soil they’re going to be dealing with. Crews sometimes will run into rocky terrain on projects, which requires blasting.

Whether they need to blast or just dig, crews have to put the dirt somewhere...

If it’s being used on the project (as is the case with the Loop 303), the dirt is hauled to where it is needed.

It is dumped in 8-inch lifts (or layers) and is knocked down with a compactor and roller until it reaches the necessary compaction rate – again, this is where pre-wetting the dirt comes in handy.

Last month, as part of our Building a Freeway series, we told you about the massive underground support substructures that help give bridges strength.

Next up in the series is an important -- but temporary -- structure that’s used as crews build a bridge, tunnel or even a box culvert.

It’s called false work, and it is used to support the structure until the concrete gets its desired strength and the bridge can carry its own weight.

Imagine that you’re building a bridge out of popsicle sticks. Those sticks can’t support their own weight at first, so you might use some blocks to give it some support until your glue dries.

Those blocks are the basic equivalent to false work…

But now what happens when your bridge is complete and it’s time to take the false work out so you have a fully functioning bridge?

With the popsicle-stick scenario, pulling the blocks out might be pretty easy once your glue is dry. But with a large bridge or tunnel, it’s not so simple.

Because the false work is so tightly jammed up against the structure that it has been supporting, taking it down safely requires something called a sand-jack.

A sand-jack is a simple concept, but really is genius when you think about it …

Basically, it is a metal, square “box” (see photo below). It gets lined with plastic (to keep moisture out) and filled with sand. A ¾-inch piece of plywood goes on top of that sand and the false work is built on top.

Because the sand is contained, none of the weight is going to settle -- there’s nowhere for the sand to go.

Now, when it’s time to take the false work down, all crews have to do is unbolt the sand jack “box” and blow the sand out of it. That gives crews a few inches of “wiggle room” to pull out the false work.

To do that safely, they’ll first secure the false work with a forklift. Next they’ll carefully remove the false work structure, except for the “lid” (not a technical term, but the best word to describe this part of the false work).

The “lid” is the top, flat part of the false work over which the deck of the bridge or culvert is built. Just pulling out its support would be dangerous … so crews hold the lid up with the use of hydraulic jacks. The jacks will set on top of the concrete structure with long rods that run through the jack, through the concrete deck, and finally connecting to the false work lid. After the false work legs have been removed, the crews will slowly lower the false work lid to the ground (imagine a mechanic jacking up a car, but in reverse).

When the false work (including the lid) is all out, the bridge, tunnel or box culvert is ready to go! Check out the video above for a look at false work and sand jacks in action. The structure being built is a box culvert that will be used as an equipment pass through during construction of the Loop 303. We'll explain more about that one soon. Stay tuned...

You know when you drive under or over a freeway bridge that it’s a massive structure…

There are the two abutments (the upright supporting structures at each end that carries the load of the bridge span), there are usually center columns or piers, and, of course, the girders and the bridge deck (the part you actually drive across).

The girders and the deck make up the bridge’s superstructure. (You can tell how much goes into a bridge’s superstructure by checking out what goes into taking one down.)

But what you don’t see is that buried beneath the bridge is part of the equally impressive substructure formed by rows of caissons – massive steel-and-concrete pillars that support and lock in place the abutments.

The substructure, which is made up of the caissons and the abutments, ensures that the bridge is secure and strong enough to support not only its own weight, but also the weight of all the vehicles that drive across it every day.

The caissons are formed by tying thousands of feet of rebar into massive steel cages that are then lifted with a crane, lowered into drilled shafts, and filled with concrete. Several feet of rebar is left rising out of the ground, which is what the abutments are ultimately secured to.

There’s no such thing as a “standard size” caisson…their lengths and diameters vary from project to project and bridge to bridge based on several factors, including the soil type and the expected and actual weights the bridge must support.

Generally speaking, caissons for most bridges in Arizona are between 40 and 120 feet deep and 5 to 12 feet in diameter.

There’s also no set number for how many caissons each abutment will require – that, too varies by bridge.

Take the three bridges being constructed for the new phase of Loop 303 in Surprise, for example. The bridge abutments at Waddell and Cactus roads are supported by 23 caissons each (46 total per bridge), while the bridge at Greenway Road, which is only partially elevated over Loop 303, requires just 20 total caissons (10 under each abutment).

The video above shows the fabrication and installation of those Loop 303 caissons. The steel cages for these particular caissons are 95-feet long and weigh about 20,000 pounds. The cages were lowered into 88-feet-deep drilled shafts and filled with 80 cubic yards (8 truckloads) of concrete each.

If you’re keeping tally…that’s 8 truckloads for each caisson, times 106 caissons, for a total of 848 cement truckloads (for just those three bridges)…and that is just part of the substructure!

The concrete for these caissons cures in about 24 hours, clearing the way for the next phase of building a freeway.

When ADOT has a freeway to build, many steps must be taken long before any asphalt is paved.

One of those initial tasks involves pre-wetting the soil, which entails pretty much exactly what you think it does … crews put sprinkler systems into place and water the dirt!

Just how long crews need to water depends on the type of soil they’re dealing with, but usually this step takes a few days.

Pre-wetting the dirt makes it easier to move, helps the crews eliminate dust pollution and allows them to bring the soil’s moisture content up to a level that enhances compaction.

If you’ve ever built a sand castle, you know it’s much easier to work with sand that’s a little wet (but not too wet). Not only is it easier to build with compared to dry, loose grains of sand, but it also gives your castle a stronger foundation to build upon.

The same principal holds true out in the middle of a road construction site …

Once the soil’s moisture content is at the optimum level, the dirt can be excavated and moved to embankments or medians or off the site completely (depending on the project).

Then it’s time for compaction. This is done with different types of heavy-duty equipment like rollers, dozers, scrapers and front-end loaders. Compacting the soil creates a good solid base for the road (think of your castle’s foundation) and pre-wetting the dirt makes this step easier.

“Water serves a big purpose in compaction,” says Loop 303 Project Supervisor Mark Wheeler in the video above. “It gives you the foundation which you build on and that equates to longevity on your roadway.”

When ADOT builds a road, the work gets started years (sometimes decades) ahead of any real construction …

It all begins with the planning phase, which includes everything from determining where a new roadway is most needed to taking a look at available funding.

From there, environmental studies are completed, public involvement is conducted and preliminary plans get designed. ADOT continues to engage the public as engineers begin developing more detailed project plans. Through each phase of the project, ADOT coordinates with other government agencies, developer/landowners and utility companies.

By the time the project is ready for construction, a considerable amount of time has been invested, but there’s still a lot of work left to be done!

(By the way, this is by no means an exhaustive list of what it takes to build a road, but hopefully you can see that it’s a big job.)

More work on Loop 303. Crews are building an underpass for construction vehicles to use during the build.

We want to give you a more detailed look at each step, so today we’re kicking off a long-term series of blog posts and videos designed to show how ADOT builds a road from start to finish.

We want to use this space to help inform people about what we do and why and how we do it.

We hope you stay tuned and look out for posts tagged with “Building a Freeway.” It all starts tomorrow with a video and blog post on pre-wetting— one of the very first steps in the construction phase.

When the editorial team at Roads & Bridges makes choices for the magazine’s annual Top 10 Roads list, many factors are considered.

But, according to Editorial Director Bill Wilson, it’s the challenges faced in building each nominated road and the project’s impact that get the closest looks.

Maybe that’s why the Loop 303 (Happy Valley Road to Lake Pleasant Parkway) made it to this year’s top 10!

There were plenty of challenges … the contractor’s “to do” list was huge and included:

• The installation of a 5.35-mile section of new freeway
  (including 18 bridges)
• Moving more than 1 million cubic yards of earth
• Placing about 40,000 linear feet of underground utilities
• Pouring roughly 340,000 square yards of concrete pavement.

And, the project certainly had an impact (check out this blog post detailing the how this portion of the Loop 303 has made a difference in the West Valley).

This section of the Loop 303 was also recognized for the significant excavation and blasting that took place during construction, along with ADOT’s commitment to replant the native plants and cacti that were moved during construction.

Wilson says the magazine has been publishing a Top 10 Roads list and a Top 10 Bridges list since 2001. This year’s list will be highlighted in the magazine’s October issue.

“I think it shows our readers what people can really do out there to successfully construct a project. People have different tactics … solutions that are out there allows our readers to learn essentially from the best,” he said.

The team responsible for this project includes contractors Austin Bridge & Road, ADOT and AZTEC Engineering. For a better understanding of what this project entailed, take a look at the blog entries we posted leading up to the May opening of the entire 14-mile stretch of the new freeway between Happy Valley Parkway and I-17. We explained how it was paved, landscaped, checked for smoothness and even what's in store for its future.

Think back to 1984. You might recall that the United States hosted the summer Olympics in Los Angeles and Michael Jackson’s Thriller snagged eight Grammy Awards. It’s also when the Maricopa Association of Governments (MAG) identified the need for a West Valley regional connector freeway later to be dubbed Loop 303.

After years of scoping, study, assessment, public input and design the Loop 303 is taking shape in the West Valley. In May, a four-lane section between Interstate 17 and Happy Valley Parkway opened; and, just last week, preliminary construction work began on the next leg in Surprise, between Mountain View Boulevard (just south of U.S. 60/Grand Avenue) and Peoria Avenue.

Many who live and work in the northwest valley have been eagerly waiting for ADOT to “turn dirt” on this six-mile segment of new highway. Right now, crews are establishing water sources so they can pre-wet the ground before excavation; surveying the alignment so utilities can be relocated; and clearing the work zone of weeds and debris. In the weeks to come, the area will become an active work zone, with construction occurring on the roadway and on new bridges throughout the six-mile area simultaneously.

This phase of the Loop 303 Improvement Project is scheduled to last about two years and will transform the existing, two-lane roadway into a modern urban freeway. By fall 2013, it will include three lanes in each direction with a median, auxiliary lanes and signalized traffic interchanges at Bell, Greenway, Waddell and Cactus Roads.

No doubt, there will be impacts to area traffic while this work is underway. ADOT will provide information about possible lane restrictions, road closures or detours in advance. In addition to traffic information, ADOT is committed to providing information about other possible impacts to the surrounding community, and provides simple ways for residents and businesses to stay informed:

• Visit our Projects page and sign up to receive email updates. ADOT sends email alerts to subscribers weekly or as needed.
• Questions or comments? Call the toll-free ADOT Project Hotline at 855.712.8530.