Potholes are small bowl-shaped depressions in the pavement surface. They generally have sharp edges and vertical sides near the top of the hole.
Potholes are created in many ways. The most common way is when water seeps into cracks in the surface of the road. Then, combined with the vibration of the tires over the cracks, this can cause the asphalt to fail. That is why there can be more potholes after it rains.
Vehicular traffic can cause the subsurface materials to move, generating a weak spot under the street. And every time that a vehicle travels over it, the damage grows until the new pothole is formed.
The City repairs more than 30,000 potholes per year using materials such as a hot patch compound and bagged asphalt.