Every once in a while, we come across some funny words in the engineering vernacular.  Recently, the word “shoofly” caught our ears when the construction tactic was deployed on the Interstate 10 Broadway Curve Improvement Project. 

We’d heard the word before. Many of us learned the words to the song “Shoo Fly Don’t Bother Me” in primary school. But what does a nursery rhyme have to do with road construction?

To get our answer, we had to dig back a century or so into history.

The song “Shoo Fly Don’t Bother Me” emerged in the 1860s, however, it was originally reportedly written by a soldier during the Civil War, according to multiple newspaper sources from the period. However, these newspaper sources don’t agree on exactly who wrote the song or the meaning of its lyrics. They do agree that it became widely popular among street performers and other entertainers popular at that time. 

What’s also known is that around the same time, railroad construction began booming in the United States. According to the Library of Congress, the number of railroad track miles tripled between 1871 and 1900, with much of that construction performed by crews of workers who entertained themselves during the long workdays by singing songs. There’s no record found that these workers specifically sang “Shoo Fly Don’t Bother Me,” but given the song’s popularity at the time and its distinct beat, which helped workers stay on-task and keep pace with each other while building railroad tracks, we’d venture a guess that it made the rounds.

So maybe it’s not too much of a stretch that in the early 1900s, the Oxford English Dictionary shows that the term “Shoo Fly” began appearing in relation to railroad construction. The first newspaper articles to use the term in 1905 were out of Los Angeles and New York. These articles referred to the construction of a “shoo fly” to detour trains around obstacles on the track. Later articles defined the shoofly as a bypass on the track. All references cited by the Oxford English Dictionary refer to the shoofly as a temporary configuration – which brings us to today.

The term has evolved to be merged as “shoofly” and is now a commonly used term in roadway and railroad construction to describe a temporary road or track detour that allows traffic to continue flowing around a construction zone. 

That’s exactly what you’ll find on southbound State Route 143 just south of University Drive.  The shoofly is diverting traffic to the right for several hundred feet, to give I-10 Broadway Curve Improvement Project crews the space they need to build a new flyover ramp that will connect SR 143 and I-10. This shoofly configuration is expected to be in place until early 2023. Because of the curving movement of the shoofly, the speed limit in this area is reduced to 35 mph. Please keep this in mind when driving through the work zone.

Be sure to watch the Interstate 10 Broadway Curve Project’s Behind the Scenes video on the “Shoofly”, at this link.

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.