It is easy to assume that potholes and damage to roads are formed due to roads being poorly maintained but that is not usually the case. There are many factors that can cause damage to roads.

The primary factors that are important to road integrity is water drainage, compaction, quality of the fill and the weight of vehicles.

Good quality material (gravel, fill) and good compaction of the ground underneath the road seal is very important to building a good quality road. This is to make sure the ground is stable and can withstand the weight of vehicles. Heavy vehicles are the ones that damage road seals. Rarotonga’s newer roads (2012+) are built to withstand a weight of 39 tonnes. That means, if any vehicles carrying loads above that weight use the roads, the road will start to deteriorate.

Additionally, the road needs to be shaped to make sure water does not pool on the road and instead runs off into good drainage systems. 

Pothole formation requires two factors to be present at the same time: water and traffic. Water weakens the soil beneath the pavement while traffic applies the loads that stress the pavement past the breaking point, which causes the road surface to crack or to sink.