If you’ve even driven down a city road, you’ve probably asked yourself “Where do all these potholes come from anyway?”. It’s a good question, but before you blame someone, wait - it might not be entirely their fault!
Potholes happen from water getting under and inside the pavement. As water naturally expands and contracts, the asphalt weakens from the structural changes. If you have trouble picturing it, imagine how water changes shape as it freezes. The more this happens, the weaker your asphalt gets. In colder temperatures, there are more freeze and thaw cycles, which can lead to potholes getting created pretty rapidly. This is also why coastal climates seem to have more potholes than other areas - there’s more freezing and thaw cycles due to the weather coming off the coast.
How Does Water Get Under Or Inside Pavement?
There are four main causes of water seeping into asphalt. In extreme heat and sun, the asphalt can weaken and crack in normal response to the weather. In freezing climates, pavement needs to be thick enough to withstand normal traffic amounts - if it gets too thin, water is likely to seep under. In all climates, water can potentially seep under along the sides of the road. If asphalt isn’t maintained, then water can seep into cracks and damages along the surface.
The good news, all of these things can be avoided to a degree. Potholes caused by cracks, weakening, and damages can be prevented by properly maintaining your pavement. Applying a seal coat when needed will help to protect the surface. Proper grading and measuring thickness of asphalt will prevent water from seeping under, as well as traffic weakening it.
Once potholes exist, they have to be filled. In cooler weather, this may lead to a temporary fix, using a throw and roll repair method as opposed to the proper construction methods. Have no fear - once the temperatures rise, hot asphalt will be applied and the potholes fixed.
In general, proper maintenance of your asphalt pavement can lead to the prevention of potholes.