Just last month we blogged about a project that’s under way on I-17 and SR 69 in Cordes Junction.

So, maybe you’re wondering why we’re bringing it up again so soon …

Well, we’re blogging about it today because we’ve got an awesome new video (see above) that details the entire project and shows footage from January when crews installed some precast girders – a milestone in the construction.

When all the work is complete – around summer 2013 – motorists are going to have a much easier time maneuvering the interchange that sits halfway between Phoenix and Flagstaff. That’s because the project includes:

• New bridges on SR 69
• The removal of the outdated on- and off-ramps
• A new I-17 interchange
• Two new bridges and ramps built over I-17 to connect with SR 69
• The construction of a new Arcosanti Road, along with the realignment of Copper Star Road and Stagecoach Trail.

“I think this is going to be a major center for the folks around here and also for the state of Arizona,” Cordes Junction business owner Jerry Schultz says in the video above.

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.

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!

A project is now under way that’s going to result in a new, modern interchange designed to handle the area’s growing needs. Work started in August and by the time construction is finished (in about two years) some of the new features will include …

• New bridges on SR 69
• The removal of the outdated on- and off-ramps
• A new I-17 interchange constructed north of the existing interchange
• Two new bridges and ramps built over I-17 to connect with SR 69
• The construction of a new Arcosanti Road along with the realignment of Copper Star Road and Stagecoach Trail.

The current intersection design forces local and through traffic to mix, which causes congestion and safety concerns. The brand new interchange will be able to separate local and highway traffic, leading to improved traffic flow and safety.

Project area map.

Recent traffic shift
Crews are now working to build the bridge structures over I-17 and just last week a traffic “shift” was put into place that will allow work to continue over the highway.

Overnight on Dec. 29 crews temporarily moved southbound I-17 traffic onto the northbound side of I-17.

The detour will be in place until the bridges are complete. But don’t worry … I-17 still has two lanes in each direction within the work zone and the lanes are separated by temporary barrier walls. Drivers also should be aware the southbound I-17 speed limit is reduced to 55 mph. Temporary construction detours also are in place along SR 69 near I-17 (see map).

Work is being completed in four phases (right now, we’re in phase two). Each phase has been designed to minimize the impact to the local community and travelers while maximizing cost-effective procedures.

For more details on the interchange and information on what future construction phases entail, stay tuned … we’ll keep you updated as the project progresses!

The official start of winter is approaching, but the cold weather is already here!

Over the past few weeks, we’ve told you how ADOT prepares for the snowy conditions common this time of year in Arizona’s high country.

Getting the snowplows ready, along with plenty of deicer ready, along with closing down certain low-traffic/heavy snow routes are vital steps, but there’s an additional action ADOT takes each year as the temperatures start to dip …

Every winter ADOT has to suspend work on projects in the state’s high country. This is necessary because it is too cold to pour concrete or place asphalt pavement (rubberized asphalt is especially sensitive to temperature variations).

But that doesn’t mean our crews just drop what they’re doing!

Work is stopped at a logical point and the work zone is generally left in a condition that doesn’t impede traffic. Drivers may notice some barricades and should be aware as they’re driving through project sites.

And as for the actual crews…ADOT workers who manage or inspect the projects either switch gears to next-year’s planning or are reassigned to maintenance for the season.

Here’s a list of projects that have either already been suspended for the winter, or will be stopped in the next week or so:

• SR 64 roadway and streetscape improvements in Tusayan
• I-17 Munds Park traffic interchange
• US 93 repaving north of Kingman (top layer of rubberized asphalt will be finished in the spring)
• US 93 repaving south of Wikieup
• SR 260 passing lanes between Overgaard and Show Low
• US 60 repaving between Springerville and the New Mexico state line
• I-40 repaving through Holbrook
• SR 87 repaving north of I-40

As ADOT employees, we naturally get a lot of transportation-related questions thrown our way by friends and family... it’s just something that comes with the job!

By far, one of the most frequently asked questions has to do with HOV lanes and why ADOT builds them after the freeway is constructed (we answer that one here, by the way).

But, another question we regularly get focuses on the rock landscaping surrounding our Valley freeways.

People want to know why we don’t just use trees and shrubs instead of rock. Others wonder why we landscape the area at all.

Well, here’s the answer...

The main purpose of all freeway landscaping is really a practical one ... it helps control erosion and dust.

According to ADOT’s Chief Landscape Architect LeRoy Brady, anything that breaks up the rainfall (such as rock landscaping) or has a root system and holds soil together is going to help handle erosion.

As for dust control, Brady says rock landscaping and other types of plant-based landscaping help simply by covering the dirt.

“Because you don’t have bare soil, you don’t have the dust. It eliminates the dust source,” he said.

The type of rock that’s used matters, too.

Brady says his department sponsored a study that researched what size and grade of rock would work best for controlling erosion. The study was completed about 23 years ago, but the information is still used today.

Not only does landscaping help with erosion and dust, it has the added benefit of improving the aesthetics along freeways!

Rock landscaping is less expensive to maintain than planting and trimming trees and shrubbery... and rocks don't exactly require a lot of water.

ADOT works with the local communities to determine how to enhance the scenery along the freeways. Take for example the landscaping project along the recently upgraded I-17 in the north Valley.

ADOT worked with the city of Phoenix to create the landscaping theme and settle on designs, which are created to reflect Arizona's heritage and environment.

Brady says "context-sensitive design" is an effort in transportation to design and construct environmentally sound projects that fit and relate to the community, “instead of something that’s foreign and has no relationship.”

Along I-17, great care was taken to create designs that really fit the community.

About 15 colorful landform graphics made of crushed granite have been created for the project. There are a few Gila Monsters that have now taken shape at the Carefree Highway interchange and along the slopes at the Jomax Road interchange there’s a design patterned after a Hohokam water bowl.

It’s a challenging prospect to take a landscaping pattern from paper to the extra-large canvas of a freeway slope...

The process starts with site visits. Crews use flexible PVC piping and rope to set patterns before using spray paint to outline the design on the ground. Metal edging is then used to create the borders for the different sections of the colored rock and then the rocks are put in place.

Landform graphics and rock landscaping aren’t the only affordable and sustainable options for our freeways.

The location of the freeway often plays a role in determining what type of landscape to go with, as it did on a recently completed stretch of Loop 303.

There’s a lot more to freeway landscape design that we’ll cover in future blog posts. In the meantime, check out ADOT’s Roadside Development Web page.

It’s not often that a tree gets wrapped up in a mystery, but a lot of unanswered questions surround one Juniper growing next to I-17.

Some Arizonans might already know about the tree – it’s actually sort of famous around the state. Sitting in the middle of the median, just north of the Sunset Point rest area, around milepost 254, this is the tree that’s secretly decorated around Christmas and the Fourth of July. For years, no one has been able to figure out who is responsible.

Earlier this month something else happened that’s equally puzzling …

On Aug. 3, the 20-foot high tree survived a brush fire that had already consumed much of the vegetation around it. Flames got so close to the tree that plastic pipes situated near the trunk were melted (the pipes serve as a watering system and were put there presumably by the same people who stealthily decorate the tree each year).

The fire started about 200 feet south of the tree and forced a closure of the highway. But, according to ADOT Highway Operations Supervisor Randy Skinner , the tree, amazingly, was not harmed.

“The fire pretty much just burned up to the tree and burned out,” said Skinner, adding fire departments from Mayer and Black Canyon City responded to the blaze.

This isn’t the first time something like this has happened.

ADOT employees, who handled traffic control as the fire burned, have seen the tree somehow survive over and over again.

“In the 15 years I’ve been with ADOT, we’ve had fires three or four times a year and the tree never gets touched by the fire,” Skinner said. “For some reason this tree doesn’t burn.”

So, what do you think protects the tree? And, any ideas on who decorates it for the holidays? Leave your theories in the comments or post them over on our Facebook page!

Memorial Day weekend is here and if you’re headed out of town you probably have your travel plans all wrapped up by now.

Hopefully those plans already include some safety preparations … if not, here are a few things to think about before hitting the road!

• Check out your vehicle’s condition before a trip. Inspect things like tire condition and pressure, oil and other fluid levels and inspect belts and hoses.
• Pay attention while out on the road and expect the unexpected.
• Get plenty of rest before traveling and take regular rest breaks.
• Be patient and alert to changing road conditions … and buckle up!
• If your vehicle breaks down or you need to change a flat tire, pull completely off the roadway. Be cautious in areas with taller grass or brush – hot vehicle components can spark a fire.
• Don’t drive under the influence of alcohol or drugs (even prescription drugs can limit your ability to safely operate a motor vehicle).
• Cell phones or satellite devices help in an emergency – make sure they are fully charged.
• Obey the posted speed limit and check for changing speed limit conditions.
• Signal in advance for lane changes and turning maneuvers.
• Take plenty of food and water.
• Slow down in areas known for high winds and dust storms and be prepared to exit the roadway if extreme weather conditions occur. Weather conditions can change and monsoon storms can arrive suddenly, creating dust-filled winds and cutting visibility along the highway up ahead.

It’s always a good idea to allow some extra travel time, too. Unscheduled closures due to crashes or other incidents, including wildfires, can affect highway travel. Existing work zones for highway improvement projects, even when work is not taking place over holiday weekends, can add time spent on the road.

A couple of existing highway work zones to be aware of – especially at the start and end of the Memorial Day weekend – are located along Interstate 10 at the Hassayampa River bridges 40 miles west of downtown Phoenix and at the Interstate 17 bridges at Munds Park 20 miles south of Flagstaff. The highways are narrowed to one lane in each direction at those locations.

One last thing … before your trip you can call 5-1-1 or log on to ADOT’s Traveler Information site at az511.gov to check on updated highway conditions around the state.

The bridges over Pinewood Boulevard in Munds Park have been carrying Interstate-17 traffic for the past 53 years and now it’s time for some well-deserved reconstruction!

ADOT has already begun the project that will rebuild the bridges and ramps on I-17 at Munds Park, an area just south of Flagstaff . Work started last month and is scheduled to wrap up by fall 2012.

When the job is finished, motorists will have two new bridges each measuring 100-feet long (they’re now just 25 feet). The bridges will also be wider to accommodate an eventual third lane planned for I-17. A new sidewalk on Pinewood Boulevard is going in, too. It will allow pedestrians to cross safely underneath I-17 (see above video).

This update is necessary because there is more traffic now then when the bridges were built in 1958. Back then there was no development in Munds Park . The bridges are just inadequate for today’s traffic.

Drivers should expect some slowing of traffic due to this project – especially over busy holiday weekends. It is expected that delays at peak holiday travel times could reach up to 45 minutes … so please plan accordingly.

Project Timeline

April 2011 - Oct. 2011: The northbound bridge will be demolished, then reconstructed and I-17 will be repaved through the work zone. Because the northbound bridge is closed, motorists traveling northbound on I-17 will be directed to a detour that crosses over the median and utilizes southbound lanes. All on and off ramps will remain open.

April 2012 - Oct. 2012: 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.