Winter 2011-2012 in the Central U.S. – and the Potholes to Come
As winter settles in, it is anyone’s guess as to whether the weather will meet expectations. But as sure as there will be cold, snow, sleet and eventually, a thaw, there is one prediction that is a safe bet: there will be potholes.
A severe period of cold and snow is predicted for the upper Midwest, including storms expected to hit Chicago, Indianapolis, Omaha, Nebraska and of course Buffalo, New York. AccuWeather.com predicted in October 2011 that in terms of temperatures, Minneapolis will get the “worst of winter’s cold alone.” The meteorological site further predicts, “bitterly cold blasts of arctic air are expected to invade the northern Plains, Midwest and Great Lakes in December through January.”
Texas, fresh off a drought-and-heat ridden summer – sometimes characterized by exploding pavement, where moisture under pavement turned to steam, quite like a pressure cooker – is expecting that “winter temperatures will be milder than normal, on average, with much-below-normal rainfall,” according to the Old Farmer’s Almanac. “The coldest periods will occur in early and mid-December, early January, and early February.”
Arkansas is expecting drier, warmer temps than normal. Just north, in Missouri, the Almanac predicts warmer and drier weather as well in winter, but a cooler, wetter spring.
AccuWeather.com’s long range expert, Joe Bastardi, is predicting “severe bouts of cold deep into Texas and Florida [that] would be capable of affecting agriculture more so than we’ve seen in the last 20 years.” He predicts this based on a combination of strong El Nino and La Nina cycles and arctic volcanic activity, such as the Icelandic volcanoes (Eyjafjallajokull in 2010, Grimsvotn in 2011 and possibly an eruption of Mighty Katla in 2012) which severely impacted air traffic in Europe in 2010-2011 and could affect global temperatures in the year or two following 2012.
The freeze-thaw heave-hos – and truck traffic
Severe weather is one thing. No one likes shivering while waiting for their car to warm up, it’s never fun to drive in icy conditions, and no one wants to get stranded in their vehicles in a snowstorm. But the real problem, insofar as potholes go, is temperature fluctuations. Added to traffic and the simple passage of time, the dance above and below the point where water freezes is what rips pavement apart.
It is not at all unusual for most regions of the country – except those that are in the sub-tropics, where freezing temperatures rarely occur – to have frequent temperature variances above and below 32 degrees Fahrenheit (0 degrees Celsius) during certain seasons of the year. This is the point where water turns to ice, of course, which causes an expansion of cracks and crevices in a roadway, followed by erosion when the ice melts, and later more expansion the next time temperatures again drop below 32 degrees. A small crack can turn into a gaping pothole in a matter of days when such conditions are right.
Exacerbating all that is traffic, as heavy vehicles roll over those small gaps in space. The pressing action of cars and trucks – especially the trucks, which weigh as much as 19,000 pounds per axel, several times more than on passenger vehicles – squeezes sub-pavement water outward. In so doing, the freeze-thaw phenomenon is spread over a larger area.
Which gets to the dilemma of roads and trucks and pavement quality: our economy depends on trucks, and trucks depend on good roads. Truck delivery is intrinsic to commerce – from ports and freight train intermodal transfer sites to retailers, manufacturers, commercial buildings and residences. When pavement is in poor condition, trucks incur damage (flat tires, broken axels – and accidents) or at least are forced to drive slower. Potholes literally slow the wheels of commerce, adding time and expense to trucking operations and those businesses that depend on them.
There are more than 3.2 million people employed as short-haul and long-haul truck drivers in the U.S., with about 15.5 million trucks in operation, about two million of which are tractor trailers (the biggest vehicles). In any given year, trucks log more than 430 billion miles on U.S. roads, streets and highways. Freight trains might be cheaper and able to move goods at lower energy costs, but they are slower and more cumbersome. In the United States, moving goods by surface vehicles (trucks on roads) commands 88 percent of all shipping dollars. This reflects a trend away from rail shipping that began with the construction of the interstate highway system in the middle of the 20th century.
Truck traffic somewhat correlates with denser population, such as is seen around cities like Miami, Fort Lauderdale, Tampa-St. Petersburg and Jacksonville, Florida. Statewide, the average annual daily traffic (AADT) actually increases at a greater rate than the increase in population in rural counties, as those counties’ interstate highways are main corridors of transportation between population centers (source: Florida Department of Transportation, Project Traffic Forecasting Handbook, October 2002).
In other words, traffic is spread evenly throughout the interstate highway system, somewhat apart from where the population centers are. Secondary highways, roads and streets of course get much more traffic in the urban areas, leading to significant pavement deterioration from vehicular traffic in combination with weather conditions. The same can be said in crossroads/manufacturing states such as Texas, Arkansas, Missouri, and Illinois and throughout the country.
Pothole blitz worked in Virginia
In the springs of 2010 and 2011, the Virginia Department of Transportation (VDOT) approached its own roadway pothole problem with a “pothole blitz.”
According to a press statement from the state’s governor, Bob McDonnell, “Virginia’s transportation network is vital to our economic prosperity and connects people to their work, homes, families and friends. Although the milder winter we experienced this year has led to fewer potholes to repair than the 161,00 filled during our 2010 pothole blitz, VDOT and its contractors promptly responded when Virginia citizens reported potholes to VDOT’s website or called their customer service center. The pothole blitz has helped to make travel safer and easier for all Virginia motorists.”
The repairs were made to state-maintained roads and interstates. It was driven by a public education campaign, asking residents to report potholes by way of VDOT, which then conducted a triage of sorts in determining where to fix roads first. Severe potholes in highly trafficked areas were given priority, fixed within 24 hours of reporting.
In online news stories about the Virginia blitz, the commenting readers complained that these potholes were given temporary filler. (Temporary repairs with lower-quality cold mix asphalt are often necessary in colder conditions, however higher-quality, permanent-fix cold mix asphalt is in increasing use by many municipalities.) The state responded by saying that reconstruction or more resilient, permanent repaving constituted the second part of this program, repairs that commenced once the freeze-thaw season had passed.