It's summer 2022 – also known as the “summer of closures” – on the Interstate 10 Broadway Curve Improvement Project. As we’ve been saying for a few weeks now, travelers should expect multiple weekend freeway closures in the project area through at least August. Our project team encourages you to plan routes ahead of time and allow extra time to get where you’re going.

We are often asked for directions to get around a freeway closure. For this project, ADOT is advising drivers to use the highways and freeways in the state highway system, rather than local roads and streets. While it may add a few extra miles or minutes to your route, highways and freeways generally provide the fastest detours. We are using our project app, The Curve, our website, i10BroadwayCurve.com, social media and other tools to share the detour routes along the state highway system with travelers, and we encourage everyone to use them.

However, on a complex project in a large metropolitan area like Phoenix, it may be a natural inclination during freeway closures for some drivers to self-detour onto local roads. For those drivers, the Maricopa Association of Governments (MAG) and ADOT are collaborating with local cities and towns in the project area on a unique program to make sure drivers can get where they’re going without too much delay and with minimal disruption to the drivers already using those local roads.

This program keeps traffic flowing by deploying traffic signal timing plans across local jurisdictions on key roads during freeway closures.

How were those signal timing plans created? Early in the project process, MAG used a traffic modeling program to determine which local roads and streets drivers would most likely use to detour themselves around freeway closures. Through the program, they identified that, among others, 48th Street, Priest Drive, Baseline Road and Southern Avenue could likely see increased traffic when I-10 is closed.

Since technology now allows for traffic signal timing to be controlled remotely through computer networks, MAG took an inventory of the types of technology installed on the signals on the identified roads to make sure their signal timing plans could be adjusted and controlled remotely. If a traffic signal needed upgraded technology, MAG worked with the local city or town to find the funding to make the upgrades.

The MAG team then looked at the expected increase in traffic during different freeway closure scenarios. On the I-10 Broadway Curve Improvement Project, freeway closures typically occur in the same areas. The MAG team studied the directions in which people were expected to travel and their possible destinations during each closure in each area. From that information, they developed signal timing plans that adjust the timing of red and green lights across a series of traffic signals along the identified local roads and streets. Now, the signals are timed to work together to keep traffic flowing along the roadway.

These signal timing plans were set into place as the first freeway closures for the I-10 Broadway Curve Improvement Project were beginning in 2021. Now, after each closure, the team reviews the data about how traffic flowed during the closure and adjusts the signal timing plans for the next closure.

It’s all part of an ongoing improvement process to make sure you get where you’re going, even when the freeway is closed.

You only have to work at the Arizona Department of Transportation for about five minutes to understand how passionate people are about their commutes. And rightly so. Travelers want to get to and from the places they need to be quickly and safely.

We understand closing a highway so we can work on it adds time, and sometimes extra miles, to a commute. With every project comes a balancing act of getting critical work completed while trying to reduce impacts to the traveling public. Many of you offer comments, questions and suggestions for us, which we appreciate.  Among the most common: 

“You shouldn’t close all of the lanes at the same time. When I lived in (enter another state here) they only closed a couple lanes at a time to do road work.”

“Why do you have to close the highways on the weekends?”

“You should do all of the work overnight when fewer people are driving.”

All fair points. But there is a method to the madness that we call “maintenance of traffic,” or MOT for short.

MOT comes into play when crews set up temporary construction zones on the highway system. While it’s critical to ensure movement of traffic through or around the work area, the foundation of MOT is keeping everyone - drivers, their passengers and construction crews - safe. That’s why closing all of the lanes is necessary at times.

Certain types of work over the travel lanes, such as relocating overhead power lines, taking down a bridge or setting bridge girders, cannot occur with drivers on the roadway below. The risk of potentially injuring travelers or damaging their vehicles is too great. Similarly, it’s not safe for workers to put down lane striping or set up concrete barriers on a multilane highway with thousands of vehicles driving by at 55, 65 and 75 mph. 

A project’s schedule is another factor in determining the size and scope of a closure. Fully closing a highway so 100% of the work is completed in one weekend can be a better alternative than partially closing the highway over three weekends so about 30% of the work is completed each time. Getting the work done more quickly benefits all of us. No one ever complains that a project finished too soon. 

That also helps to explain why not all of the work is done on weeknights, and why weekend closures are necessary. 

Weeknight highway closures are actually pretty common. Crews do a significant amount of work while most of us are sleeping. ADOT’s overnight closures generally occur from 9 or 10 p.m. to 4 or 5 a.m., ensuring the highway is fully open for your weekday morning commute.

Limiting a project to overnight work only - and not allowing for weekend closures - will undoubtedly add time (and cost) to a project. Consider this:

Closing a freeway between a Friday night and a Monday morning provides about two full days for work to get done (after you subtract the hours needed to set up and take down the traffic control barriers and signs).

If a project has 25 weekend closures in a year that adds up to 50 work days. Over the course of a three-year project, it’s 150 work days - or five months.

Finishing a project five months earlier is a good thing; motorists get to take advantage of the improvements sooner and - depending on factors such as fuel prices and inflation rates - the project will often cost less. 

We know many people are out and about on the weekends. Yet, an even greater number of people use our urban highways on weekdays. Although we saw a dip in traffic volumes during 2020, our urban highways are back to pre-pandemic levels during the work week. 

That doesn’t mean work won’t get done on week days. We collaborate with our contractors to develop schedules that allow them to have crews in the field without impacting drivers. On the Interstate 10 Broadway Curve Improvement Project, for example, work is happening on weekdays, but behind concrete barriers in the median of I-10 and on the outside of travel lanes. This allows our workers to make progress while we fully maintain all of the travel lanes zone during peak travel times.  

We can also make considerable progress - and more quickly - by allowing extended closures of on or off ramps. For example, the I-10 Broadway Curve project team is planning to close the ramps 32nd and 40th streets for up to 45 days each to make improvements. Both ramps won’t be closed at the same time, however, so motorists will have a convenient, nearby alternate route. Extended ramp closures like these make it possible for crews to establish a work zone and keep it in place until they’ve completed the job. Again, this is a more time- and cost-efficient method vs. setting up and tearing down the work zone daily.

What you might not know is we don’t schedule work that requires highway closures during our “holiday moratorium,” which begins in mid-November and continues until the first work day after New Year’s Day. We also don’t close a highway that provides access to a special event with 30,000 or more people. Our highways also remain open over state holiday weekends when we know more drivers will be out enjoying our beautiful state.

Unless there is an unplanned incident on or next to the highway (crashes, wildfires, for example) we strive to provide as much information as possible in advance so you can plan ahead. We encourage you to allow extra travel time and use the detours we provide. You can also download the free AZ511 app to get real-time highway conditions statewide.

We work hard every day to achieve our vision of becoming the safest, most reliable transportation system in the nation - but sometimes that means we need to close a road. 

Do you think you’re #AheadOfTheCurve when it comes to Arizona’s largest urban freeway reconstruction project to date? Let’s find out! 

Take our quiz and let us know how you do. If you get all five questions right, then call yourself a Broadway star!

For more information about this project, visit i10BroadwayCurve.com and don’t forget to download the free project mobile app, The Curve, for access to real-time traffic updates.

As the project manager for the Interstate 10 Broadway Curve Improvement Project, I’ve come to expect the unexpected. It’s all part of leading the Arizona Department of Transportation’s largest-ever urban highway reconstruction project: a four-year, $776 million effort along the busiest 11 miles of highway in the state.

Yet one aspect of this project has taken me by surprise: the number of people who risk their lives, and the lives of others every day, to save about three minutes. That’s how much time you save when you drive the 11 miles of I-10 between the Loop 202 (Santan/South Mountain Freeway) and I-17 at 75 mph vs. the posted speed limit of 55.

Three. Whole. Minutes.

Speeding saves a small amount of time, yet takes many lives. Consider this:

• In 2020, 337 people were killed in speed-related crashes in Arizona and another 15,839 were injured.
• Speeding is one of the major causes of work-zone crashes.
• In 80% of fatal work-zone crashes, the driver and his or her passengers are killed. 

Construction crews are also at risk, even when they work behind barriers. Their hard work makes our highways safer and more efficient. Just like you, they want to get home safely to their families, friends and pets every day.

Our project team decided not to sit back and accept that dangerous drivers speed through our work zone. Instead, we’re taking actions, like adding DPS patrols and using overhead message signs and billboards to share safety information. Recently, I joined my project team colleagues Kole, Marcy, Edika and Jeremy to participate in a public service announcement (PSA) asking drivers to slow down. We’re not actors; we're people who work on highway projects, and who truly care about your safety and that of our crews in the field. I hope you’ll watch our PSA and share it with others.

We also care about the time, expense and inconvenience involved with putting the roadway back together after someone collides with a barrier, guardrail or attenuator. That’s been happening about twice a week since our work zone was established and - you guessed it - the No. 1 contributor is speed. Thankfully, most people aren’t seriously injured in these types of crashes, unless you count the headache of having to fix or replace their vehicles and paying higher insurance rates.

Repairing and replacing the damaged equipment requires closing I-10 travel lanes or ramps and putting detours in place - detours that often add more distance and time to a driver’s commute. How ironic.

While our team is hyperfocused on our work zone along I-10 in Phoenix, Tempe, Guadalupe and Chander, we hope you’ll remember that speeding through any work zone can be deadly and costly, and slows everyone down in the long run. Are the few minutes you might save by speeding really worth it?

Please, slow down.

If you’ve driven on any freeway, chances are you’ve seen the aftermath of vehicle collisions that just occurred, or evidence of crashes from the recent past: guardrails smashed into accordion-looking metal clusters, pieces of freeway signs bent and twisted, or tire marks on barrier walls. Sometimes you might even wonder, “How in the world did a tire mark get that high up on the wall?”

Most crashes are the result of driver behavior. According to the Arizona Department of Transportation’s 2020 Crash Facts report, driver behavior is a leading factor in more than 90% of crashes. Speeding, impairment, aggressive driving, and distracted driving are primary contributors -- yet all of these factors are 100% preventable.

Members of the Interstate 10 Broadway Curve Improvement Project team see the damage that crashes cause all too often. In their work zone, speeding drivers are the most common culprit despite the posted 55 mph speed limit. In an effort to reduce the number of crashes in their 11-mile work zone, they participated in a new public service announcement that reminds drivers to slow down and drive 55.

I-10 Broadway Curve Improvement Project team members featured in the PSA (pictured above) are Marcy McMacken, ADOT Community Relations project manager and project spokesperson; Edika Zarbroudi, P.E., ADOT project supervisor; Jeremy Sala, P.E., resident engineer; Kole Dea, P.E., ADOT senior resident engineer; and ADOT Project Manager Amy Ritz.

Project Manager Amy Ritz, who’s worked at ADOT for 16 years, said she hopes this PSA encourages motorists to do one small thing while traveling through construction project work zones: slow down. By just slowing down, this small action will help get everyone home safely to their families, she said.

Kole Dea has worked at ADOT for 15 years. Dea says that when crews are in active work zones, their worksite can be very close to the freeway with thousands of vehicles driving by. When drivers slow down, the chances of a crash decrease, and work-crew safety increases.

Jeremy Sala, with Civil Solutions Engineering and Management, part of the project's general engineering consultant team, who is working with ADOT, oversees construction on the east end of the project. Sala believes drivers should observe the speed limit and obey traffic signals to ensure construction crews stay safe as they work on the project for the next two and a half years. 

Edika Zarbroudi wants to remind motorists that when they slow down in construction work zones, they will arrive at their destination safely. Speeding causes crashes, which only create more traffic congestion and longer commute times, which slow everyone down, she said. 

Marcy McMacken, who joined ADOT’s Major Projects communication team in November 2021 and helped produce the PSA, said her main goal was to create a safety message that not only included the faces of project team members who are regularly out in the work zone but also provided a visual of the costly damage caused by high-speed vehicle collisions. McMacken hopes both of these will encourage motorists to slow down in active work zones.

Is there such a thing as TMI about TMAs? TMAs (truck-mounted attenuators) are also called crash cushions, but there’s nothing cushy about them when it comes to keeping drivers and workers safe. 

All kidding aside, we’re serious about your safety and that of workers during the state’s largest urban freeway reconstruction project, the Interstate 10 Broadway Curve Improvement Project. 

Attenuators, whether truck-mounted or fixed, are hard to miss (hint: the yellow and black stripes usually give them away) and you’ve probably seen them along the project area, which spans I-10 for 11 miles in both directions from the Loop 202 (Santan/South Mountain freeways) to Interstate 17. Additional work is occurring on one mile of eastbound and westbound US 60 between I-10 and Hardy Drive and on 1 mile of northbound and southbound State Route 143 between I-10 and the Salt River. 

The mobile TMAs act as a safety barrier between the workers on the job and freeway traffic. A project crew member parks the TMA behind the work crew; if a driver veers into the work site, the vehicle will hit the attenuator instead of a heavy truck or a construction worker. 

Fixed attenuators stay in one place in active work zones. They are usually installed near off-ramps or medians and anywhere a temporary barrier wall comes to an end. 

Fixed or mobile attenuators are designed to absorb the impact of a crash, protecting workers and helping to reduce injuries to motorists and damage to their vehicles. But anytime one is hit, people can be seriously injured. Also, the attenuator must be repaired or replaced right away, which is costly and requires additional lane closures and delays for drivers.

Work zones will be shifting throughout the length of the Interstate 10 Broadway Curve Improvement Project, and fixed attenuators will be added and removed as needed during construction. Mobile TMAs will follow and protect workers for the next three years. Watch for these as you drive through the project area! 

So please slow down, avoid distractions and give our attenuators your full attention. 

All about attenuators: /adot-blog/all-about-attenuators