Roads and Footpaths deteriorate in a number of ways:
Road traffic wears the road surface away causing it to become polished and slippery
The sun’s UV rays cause bitumen in the road surfacing material to oxidise. The road surface becomes brittle and starts to lose surface chippings
Once brittle, the road surface is prone to cracking or crazing.
Cracking can also be caused by extended dry, wet or cold periods where clay and chalk soils shrink or swell. In clay soils this is very common near trees where roots go under the road or footpath.
Cracks allow water to penetrate the road/footpath structure softening the foundations giving rise to deformation (undulations in surface profile i.e. rutting) and potholes
Soil is washed into cracks and enables weeds to take root, causing more cracking
Water present in foundation material of thinly constructed roads and footpaths can freeze and heave thus undermining the road or footpaths’ ability to withstand heavy traffic, leading to more potholes.