In the animated series “Avatar the Last Air Bender,” key characters are able to manipulate (bend) the elements of air, earth, wind and fire. Together, they are responsible for maintaining harmony between nations and the spirit world. Here in Arizona, while there is no one central person who manipulates aggregates, there is a thriving rock mining industry that maintains the state’s transportation and infrastructure. Without aggregates, the harmony of our most relied-upon roadways, airports and other travel pathways would literally crumble. 

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Despite the necessity of aggregates to the integrity of Arizona’s transportation and infrastructure, overall funding shortages could present problematic outcomes. Back in 2016, KJZZ quoted Maricopa Association of Governments’ (MAG) Eric Anderson saying, “When you buy a gallon of gas, 18 cents goes to the state to fund transportation projects. That amount has stayed the same for more than 20 years while cars have become more fuel efficient.”

Aggregate funding: Yellow light ahead

Anderson then went on to add that by 2040, MAG estimates the region will need more than $15 billion to cover freeway and highway costs.

“Many gas taxes in the states are antiquated back from the ‘80s when they were set,” says Jeff May, president of Mountain West Division, Vulcan Materials Company. “And our taxing mechanism that supports infrastructure predominantly comes from our sales tax, which unfortunately goes to a general fund and then anybody can get their hands on it.”

Not having a defined mechanism for transportation, May notes, is concerning when you have a city growing as fast as Phoenix (and Tucson). It also makes it difficult for businesses in the aggregate industry to prepare for growth if they are unsure of how transportation and infrastructure investments will flow. 

“I think more transparency and visibility to the funding mechanisms and the way that that money is going to be spent, gives us much more confidence in investing in our businesses,” May says. 

If you’re curious about how investments in transportation and infrastructure specifically correlate to the aggregate industry, consider these facts: A one-mile stretch of freeway requires an estimated 38,000 tons of aggregate material; a metropolitan airport requires 1,320,000 tons of aggregate material and aggregates make up 94% of asphalt pavement and 80% of concrete. 

Additionally, 90% of aggregates are used within 50 miles of where they are mined. 

This last point is extremely important to consider, and here’s why, according to May: “If you look at the Gulf Coast of the U.S., essentially from Galveston and Houston, all the way around to the west coast of Florida, all the way around to the northeast coast of Florida, there really isn’t any aggregates in that part of the world,” he explains. “So, they’re either railed in or boated in from offshore. We don’t have that problem [in Arizona] thankfully.”

But what Arizona does have, May continues, is a dwindling supply of aggregates in Arizona markets, particularly Phoenix. This is partially due to shortages of available land for the mining of aggregates. “What you do by taking aggregate sources from the market is you push the rings of the supply further and further out from the epicenter of where they’re needed.”

Once the supply chain parameter extends further out, prices rise significantly. According to Caltrans, if transportation distances were reduced by an average of 15 miles, it would result in a 42% savings in material costs. 

“If we’re not careful, we’re going to increase the cost of construction and infrastructure substantially because of the lack of local [aggregate] sourcing,” May says. “And that is going to eat up any amount of surplus funding or taxes.”

Future-planning leads to green light for aggregate industry

Even with future transportation and infrastructure funding uncertainties, combined with potential supply chain problems, Arizona Department of Transportation (ADOT) Director Jennifer Toth sees signs of positive traction. “Funding is always a hurdle, but we still are working on innovative and cost-effective strategies to improve our infrastructure,” she says. “For example, ADOT is choosing to prioritize investment in our existing pavement, to keep our current system in as good condition as possible.”

Toth goes on to explain that technology provides additional proactive solutions. “Over the past several years, ADOT has adopted — and fully implemented — bridge and pavement management systems to aid planning for the preservation of these important assets. These sophisticated software systems quickly perform millions of calculations, allowing ADOT’s engineers and planners to predict bridge and pavement deterioration for the entire network over many years.”

These systems also enable the exploration of multiple scenarios to identify the most cost-effective strategies for the long-term management of the assets Toth mentions.

Technology, according to Toth, also allowed ADOT to install an adaptive traffic signal system on SR 77 for about 13 intersections in Tucson, monitoring traffic conditions on the mainline and adjusting ramp signal timing that slows or increases ramp traffic merging onto the freeway, improving traffic flow on the highway.

Additionally, ADOT is a member of the Institute of Automated Vehicles (IAM), participating with universities, the private sector and other government entities to advance support in Arizona for automated vehicle technology. 

“The agency participates in MAG’s Emerging Technology program, where we recently successfully piloted traveler information messages to connected vehicles using cell phone technology,” Toth says. “ADOT piloted messages communicating work zone locations, curve speed warnings and identified where traffic had slowed considerably, warning drivers ahead of time to slow down. All of this was communicated audibly using cellular technology.”   

Even with potential transportation and infrastructure funding challenges afoot, both May and Toth point to effective state planning for the future.

“I think the state has done a really good job of putting forth a really, really good vision and plan for the infrastructure growth,” May says. “There’s a lot of information out there that supports — going back decades — when folks that started putting together the highway plan, actually manifested over time — with the Red Mountain Freeway as an example. All that was pre-planned.”

Adds Toth, “ADOT actively plans on a regular basis, through standardized processes, to assess future growth needs. We’re currently in the middle of the state Long-Range Transportation Plan process, which looks out at needs through the year 2050, more than 25 years in the future. This comprehensive planning process helps us take into account population growth and its forecasted impact on the transportation system.”