The phenomenon is altering weather patterns across the U.S. – placing new burdens on highway maintenance crews and budgets in dozens of states.
Much as meteorologists predicted, the el niño winter of 2015-2016 is turning into a monster. The immediate effects of heavy rain and flip-flopped temperatures – it was warmer in Boston (69 degrees F) and New York City (72 degrees F) on Christmas Day 2015 than in many parts of the Southwestern US (e.g., Phoenix was in the 50s) – allowed some to enjoy the outdoors more than is normal, while floods and tornadoes wreaked havoc and loss of life in Mississippi, Texas and Missouri.
The extreme moisture in Texas and surrounding states was followed with a wave of EF-4 classified tornadoes. Hours later winter weather conditions stretched from Texas on through Oklahoma, Arkansas, Missouri and Illinois. Severe rain covered much of Mississippi, Alabama and Tennessee.
What will be obvious to anyone driving a car, truck or bus in the months to come in almost every region is that potholes caused by weather will be more numerous. Those warm holiday temps were quickly followed in the new year with dips below freezing in most northeastern and Great Lakes region cities, causing the freeze-thaw cycles that are a primary cause of asphalt breakdown. Meanwhile, extreme moisture and flooding, sometimes mixed with freezing temperatures, are conditions that also undermine streets, roads and highways.
The truth of pavement, potholes and weather is that in the aftermath of heavy moisture and temperature fluctuations potholes are just about inevitable. Highway superintendents are familiar with this, particularly those in the northern plains and northeastern states where the thermometer might dance a few degrees above and below 32 degrees F in February, March and April. When and where possible, routine maintenance of small holes and cracks under such conditions can prevent those crevices from getting bigger.
But potholes also form in Miami, Los Angeles and Honolulu – because moisture and freeze-thaw cycles aren’t the only things that cause pavement to break down. Traffic, heavy loads in particular, as well as high temperatures, also cause cracking and shifting that ultimately undermine the sublayers of roads. All roadways need maintenance – the earlier the better.
Previous large el niño years provide some indication of what to expect in the winter, spring and summer of 2016. News reports from 1998, the most recent “very strong” cycle of the phenomenon, indicate that by early March of that year – when Los Angeles received 22.83 inches of rain in just three months – there were more than $137 million in damages to California highways (accounting for inflation, that would be almost $200 million in 2015). One pothole was reportedly 20 feet wide and five inches deep. As previously reported on Pothole.info, damage to vehicles can cost hundreds or thousands of dollars to individual motorists due to tire blowouts, cracked rims, alignment issues and broken axels. The Independent Insurance Agents of America report that pothole damages to all vehicles in 2013 cost $5 billion.