Do you remember the last time you drove down an Indianapolis road without turning to avoid a pothole? Can you drive to work or the store without commenting to yourself, or perhaps a passenger in the car, about the size of a particular hole? Maybe you say it’s more like a crater than a hole (I know I have).
Indiana has a hole problem.
A recent study from QuoteWizard, a site that sells insurance by Lending Tree, looked at internet searches for potholes and repair questions. It found that Indiana was ranked second across the country where road craters caused the most problems.
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Holes may seem like an infrastructure problem rather than an environmental problem. And without a doubt, deteriorating infrastructure is at the core of Indianapolis’ pit woes, coupled with limited budgets and overstaffing. In fact, Mayor Hogsett and the Department of Public Works have approved overtime for road maintenance crews to work filling potholes around the city this spring.
All that said, environmental factors do play a role – and maybe even more than you think. That crossroads (no pun intended) is exactly what we’ll be seeing for this week’s Scrub Hub.
We will explore the question: How is climate change impacting the hole? And does that make the hole problem worse?
To find the answer, we spoke with someone from the city’s Public Works department and saw what research has to say about the disturbing hole.
Short answer: Crack to hole to crater
In order to understand how climate change can impact holes, it is important to know what causes them in the first place. Despite what many people might think, it’s not just a matter of old, broken roads. Rather, it is the result of the weather.
Just as our bodies may feel a little stiffer in winter, roads have the same problem. As temperatures cool, asphalt becomes less flexible, which makes it more susceptible to cracking.
When moisture enters the crack and freezes, it expands. Then when the temperature warms slightly and the ice melts, it contracts — simple physics.
As the freeze-thaw cycle continues, the cracks get bigger and create pockets in the asphalt. After that, it didn’t take long for the surface to crumble as a nearly two-ton car drove past. Other cars disperse the debris and scrape at the edges as they pass by—and thus a hole is made.
Potholes are possible in asphalt and concrete roads, the latter being more resistant to wear and tear while asphalt is more susceptible to conditions causing potholes. And most roads in Marion County are asphalt, according to DPW spokesman Ben Easley.
“It’s temperatures above and below freezing in one day that really spoil the streets,” he said.
Since early December 2021, the Indianapolis region has experienced at least 36 days where temperatures swing above and below 32 degrees Fahrenheit in a 24-hour period, according to a review of IndyStar data from the National Oceanic and Atmospheric Administration. That’s almost a quarter of the city’s winter days ready to cause trouble.
Long answer: Climate change will make the problem worse
Indianapolis and the state as a whole are used to seeing winters where temperatures drop below freezing and stay there or hover just above them. Those were good days, said Easley.
However, consistently colder days seem to come fewer and farther in between as the effects of climate change are felt across the country and here in Indiana.
Climate change projections over the next few decades suggest that pit problems will become more common in Midwestern cities, according to the study. Most freeze-thaw cycles have historically occurred in places like Missouri, but they will become less frequent in those areas as they move north.
Studies from the Purdue Climate Change Research Center show that Indiana is experiencing greater temperature fluctuations and fewer very cold days than it did a few decades ago, and the trend is only expected to increase by mid-century. Climate change also brings greater amounts of precipitation, particularly wetter winters with more rain than snow.
Such weather is completely right — or wrong — to produce holes.
“The right conditions for the pit are more regular than ever,” says Easley. “Cycles of thawing on top of additional rainfall are ruining roads.”
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So far this year DPW has filled more than 169,000 holes across Indianapolis. There were also more than 27,000 pit service requests filed with the city in 2022, according to Easley.
However, it is difficult to draw conclusions from the data whether climate change is causing more demand for holes because the reporting system is only a few years old and thus cannot show long-term trends. It also counts the number of calls or requests made rather than the number of holes reported.
In addition, the DPW recognizes the relationship between climate and road conditions (but emphasizes that they are not climatologists).
A 2017 report from the US Department of Transportation supported this prediction and said an increase in average air temperatures during winter is likely to affect the freeze-thaw cycle and road infrastructure. It added that areas experiencing more winter days above freezing may have to adjust or extend road restrictions.
Indianapolis isn’t the only place experiencing this problem. So are Kansas City, Boston, and others.
So what can be done to try to prevent this hole problem, especially as it is predicted to get worse?
The city regularly assesses its road needs to determine where it can fill holes for now and which roads require more extensive work. As a middle ground, Indianapolis has completed more strip patching in the last five years. That’s where it will lay a new surface along the extended section of the road with significant problems.
DPW is also working to improve the base layer of roads that are frequently traveled when they are demolished for larger construction projects — which is exactly what happened with the work on Delaware Street in downtown Indy, Easley said.
While concrete is more resistant to potholes, it is also more expensive and many city budgets cannot afford such a road surface.
That’s why many city engineers keep their ears open and hope for new technologies and advances that will help keep Indianapolis’ streets catered for. Self-healing concrete, anyone? This may not be so far-fetched.
If you have further questions about climate and infrastructure, or any other topic, please let us know! You can ask us by submitting a question via our Google form below.
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Contact IndyStar reporter Sarah Bowman at 317-444-6129 or email at sarah.bowman@indystar.com. Follow him on Indonesia and Facebook: @IndyStarSarah. Connect with IndyStar environmental reporters: Join The Scrub on Facebook.
The IndyStar environmental reporting project was made possible through the generous support of the non-profit Nina Mason Pulliam Charitable Trust.