A pothole happens when the surface of a road or footpath has been worn away and a hollow forms.
As the road surface ages it becomes more porous, and rainwater gets in through cracks. In wet weather the pressure created by traffic passing over the area forces water further down into the road surface, weakening it.
In winter, as the temperature changes between freezing and thawing, there is a faster deterioration of road surfaces, because the water filling cracks freezes and expands, loosening chunks of the surface material.
Once a pothole has formed it will quickly grow as traffic continually dislodges and removes weakened and broken pieces of the surface.
Our inspectors check roads, footways and cycleways for potholes regularly. Quieter routes are inspected less often, so we ask you to help us identify and report potholes. When you report a pothole we log it and schedule a repair where required.
You can find out more about how often we carry out our inspections in our Highway Safety Inspection Manual.
How long it takes us to repair a pothole and prioritising repairs
When you report a pothole it is inspected within 3 working days and a repair will be planned if it meets the intervention levels set out in our Highway Safety Inspection Manual. In some cases we may do a temporary repair and a permanent repair will be carried out within 28 days.
Pothole repairs are prioritised depending on their size and where they are. We also take into account the amount and speed of traffic using the road, and where the pothole is in the road.
As a general rule, potholes in the road that are 40mm deep will be repaired within 28 days, the same timeframe as for potholes on a footway or cycleway that are 20mm deep. These response times are reduced to 24 hours for busy A and B roads and town centres.
You can find more information about our response times in our Highway Safety Inspection Manual.
Paint marks on the road
We make paint marks on the road to help us identify the exact spot to carry out the work. The markings used (lines, dots or letters) have no particular meaning. If a member of the public adds additional marks, this will not result in additional work being done.
How we repair potholes
A pothole repair involves 'cutting out' the weakened area. The hole is then cleaned out and painted with a coat of a liquid bitumen binder which acts like a glue when the hole is filled with a hot layer of road surface material, which is then compacted.