Potholes are common occurrences on roads, especially during winter. These depressions in the road surface can pose safety hazards for motorists, cyclists, and pedestrians.
Definition of a pothole
Knowsley Council defines a pothole as a defect in the road surface that is 40mm or more deep. If a section of the road deteriorates but is less than 40mm deep, it is not considered to be a pothole.
Factors contributing to pothole formation
Several factors contribute to the formation of potholes:
Road age and deterioration
Over time, road surfaces age, becoming less flexible and more susceptible to cracking. This makes them more vulnerable to damage from water, traffic, and extreme temperatures.
Water ingress
Water seeping into cracks in the road surface can freeze and expand when temperatures drop. This repeated expansion and contraction process weakens the road surface, leading to potholes.
Heavy traffic
Heavy traffic puts excessive wear and tear on road surfaces, accelerating the deterioration process and increasing the likelihood of potholes forming.
Utility trenches
Excavation work for utility trenches can disrupt the integrity of the road surface, creating weak spots that can develop into potholes.
Extreme temperatures
Extreme heat and cold can also cause the road surface to expand and contract, leading to cracks and potholes.
Identifying potholes
Roads in Knowsley are regularly inspected to ensure they remain in a safe condition. All defects are recorded and repaired in accordance with Knowsley’s policy for highway safety inspections, available to download below.
The frequency of inspections is based on the road type and the traffic using it.
Table 1: Carriageways
Category |
Category name |
Short description |
Long description |
Frequency |
| 1 | Motorway | Limited access motorway regulations apply | Routes for fast moving long distance traffic. Fully grade separated and restrictions on use. | Weekly |
| 2 | Strategic Route |
Trunk and some Principal 'A' roads between Primary Destinations |
Routes for fast moving long distance traffic with little frontage access or pedestrian traffic. Speed limits are usually in excess of 40 mph and there are few junctions. Pedestrian crossings are either segregated or controlled and parked vehicles are generally prohibited. | One month |
| 3a | Main Distributor |
Major Urban Network and Inter-Primary Links. Short-medium distance traffic |
Routes between Strategic Routes and linking urban centres to the strategic network with limited frontage access. In urban areas speed limits are usually 40 mph or less, parking is restricted at peak times and there are positive measures for pedestrian safety. | One month |
| 3b | Secondary Distributor |
Classified Road (B and C class) and unclassified urban bus routes carrying local traffic with frontage access and frequent junctions |
In rural areas these roads link the larger villages and HGV generators to the Strategic and Main Distributor Network. In built up areas these roads have 30 mph speed limits and very high levels of pedestrian activity with some crossing facilities including zebra crossings. On street parking is generally unrestricted except for safety reasons. | One month |
| 4a | Link Road | Roads linking between the Main and Secondary Distributor Network with frontage access and frequent junctions | In rural areas these roads link the smaller villages to the distributor roads. They are of varying width and not always capable of carrying two way traffic. In urban areas they are residential or industrial interconnecting roads with 30 mph speed limits random pedestrian movements and uncontrolled parking. | Three monthly |
| 4b | Local Access Road | Roads serving limited numbers of properties carrying only access traffic | In rural areas these roads serve small settlements and provide access to individual properties and land. They are often only single lane width and unsuitable for HGVs. In urban areas they are often residential loop roads or cul-de-sacs. | 12 monthly |
Table 2: Footways
Category |
Category name |
Short description |
Long description |
frequency |
| 1(a) | Footway | Prestige Walking Zone | Very busy areas of towns and cities with high public space and street scene contribution. | One month |
| 1 | Footway | Primary Walking Route | Busy urban shopping and business areas and main pedestrian routes. |
One month |
| 2 | Footway | Secondary Walking Route | Medium usage routes through local areas feeding into primary routes, local shopping centres etc. | Three monthly |
| 3 | Footway | Link Footway | Linking local access footways through urban areas and busy rural footways. | Six monthly |
| 4 | Footway | Local Access Footway | Footways associated with low usage, short estate roads to the main routes and cul-de-sacs. | 12 monthly |
| A | Cycleway | Cycle lane forming part of the carriageway, commonly 1.5 metre strip adjacent to the nearside kerb. Cycle gaps at road closure point (no entries allowing cycle access). | As for Roads | |
| B | Cycleway | Cycle track, a highway route for cyclists not contiguous with the public footway or carriageway. Shared cycle/pedestrian paths, either segregated by a white line or other physical segregation, or un-segregated. | Six monthly | |
| C | Cycleway |
Cycle trails, leisure routes through open spaces. These are not necessarily the responsibility of the highway authority but may be maintained by an authority under other powers or duties.
|
12 monthly |
Potholes and other defects may occur between these inspections, particularly following adverse weather conditions. This is why people must report them.
Response times for repairing potholes
The severity of the pothole and the urgency of repair is determined by the risk it poses to road users. Factors taken into account include location, size and depth of pothole; traffic type, speed and volume; road type, alignment and visibility; and also the position to cycle trails and leisure routes through open spaces. road width.
Category 1
Defects that represent an immediate or imminent hazard, where not providing an immediate response could significantly endanger the safety of road users, will be made safe or repaired within two hours.
Category 2
Defects that fall within the investigation levels below will be made safe or repaired within 24 hours.
Category 3
Defects that fall within the investigation levels below will be made safe or repaired within 14 days.
Category 4
Defects that fall within the investigation levels below will be made safe or repaired within 28 days.
How potholes are repaired
Repairs will be completed within the timescales above and carried out by the council’s term maintenance contractor.
Permanent repairs will be carried out straight away. In some circumstances, a temporary repair is carried out as a short-term measure, with a permanent repair scheduled soon after.
Temporary repairs will also be considered when there are extensive patching or resurfacing works programmed.
A typical permanent repair would see the area of the road around the pothole cut out to give a clean vertical edge. Any loose material is removed from the area being repaired and is then painted with liquid bituminous binder. The area is filled with a hot bitumen-bound material, which is raked and compacted to the level of the surrounding road.
Performance management
Performance will be monitored and managed appropriately with the aim of achieving the following response times:
| Response times | |
| Response category | Target % repaired |
| Category 1 - 2 hours | 98% |
| Category 2 – 24 hours | 95% |
| Category 3 – 14 days | 95% |
| Category 4 – 28 days | 95% |
How repairs are paid for
Pothole inspections and repairs are funded from Knowsley Council’s highway maintenance budget and from the government’s Pothole Action Fund. More information on how and where the pothole action funding was invested in Knowsley.
How to report a pothole
Potholes and other defects can happen very fast, and the council may not be aware of them, so any reports are helpful.
Reported defects are assessed, and where they meet the intervention criteria set out in the Highway Safety Inspection Policy, then repairs will be undertaken.
Report a pothole here
or contact 0800 0232334.