Lever & Ecker April 22, 2015 Slip Trip & Fall
There’s nothing that will ruin your morning jog more than doing a face plant on the road after tripping on a pothole. It could cause you serious injury, time away from work, and at least a lot of personal embarrassment. The DOT in NYC strives to keep roads in good condition and accepts pothole repair requests from locals who want to help better their community. The DOT only considers potholes actionable if they are at least one foot in diameter and at least three inches deep. But how do potholes get to this point, how are they made?
In order to discuss how potholes form, we must first understand why roads are constructed the way they are. Most roads are formed by laying layers of different material down, all of which perform some role to help protect the road, make it driveable, or have easy upkeep. The bottom layer of the road is typically made up of packed earth and gravel, or a layer of bricks in many old cities, for drainage. On top of this drainage layer, most roads are typically covered in a layer of asphalt. Asphalt is basically a protective layer for the road, made up of aggregate gravel, oily by-products, curatives, and bitumen. This gooey mixture is poured over the road, left to dry, and then it serves its purpose by repelling snow and rain, forcing it to drain on the shoulders of the roads and keeping road travelers a bit more safe.
Over time, however, the stress of traffic and the heat of the sun result in cracking of the asphalt layer. Once the damage has begun, it’s hard to stop further damage from occurring.
As mentioned above, normal traffic and heat stress cause the asphalt to break on roadways. But how does it go from minor cracking to dangerous craters in the road? Once the protective layer that is supposed to deflect rain and snow from the road cracks, this harmful water seeps down into the road all the way down to the base layer of loose gravel and earth. This still doesn’t seem like that big of a deal. Instead of deflecting the water to the shoulder of the road, now the water is just going into the materials that make up the bottom layer of the road. No harm, no foul…right? This may be fine in the summer, or even parts of spring and fall in some regions of the country, but winter brings a whole new set of problems. Rain can seep down into the road all year with very few problems, but upon the first freezing temperature, irreversible road damage takes place.
The water in the gravel and earth hits the freezing point and begins to turn to ice, thereby expanding. With nowhere else to expand, the water is forced to expand outward and upward, moving dirt and gravel with it. As temperatures go through cycles of warm and cold, water continues to expand and melt, pushing gravel and dirt further out and leaving a hollow space where the ice used to be. As travelers continue to drive over the hollow ground and the now-thin layer of asphalt, the stress added by these vehicles eventually causes the layer of asphalt over the divots to collapse. Once the road has collapsed, it’s only a matter of time before additional rain and snow eat away at the broken asphalt and exposed gravel, leaving a widening and deepening pothole for drivers to contend with.
As potholes present increasing problems, the DOT must do something to remedy the condition of roads. There are two main ways to fix potholes, a temporary and permanent fix. The temporary fix consists of pouring a winter asphalt mix into the pothole after clearing it of debris. The soft mix is used to prevent car damage until road crews can make the time to perform a permanent fix, the damage is expected to return after only a few months. The permanent fix is a summer mix that can only be applied in warm, dry weather. Typically road crews spend more time preparing the road surface for the mix and reroute traffic to let it dry properly as the repair should last several years.
Potholes are a problem that can’t really be prevented without a major overhaul of road condition technology. They are potential dangers that are part of nearly every road and can cause some serious damage. When walking or running on roads potholes can be especially dangerous for hazards such as trips and falls. Simply catching the toe of a shoe on the lip of a pothole could result in a broken bone or loss of balance into traffic. Potholes present many dangers and it’s important that they get fixed in a timely manner.