Glossary of Highway Maintenance Techniques
Our roads and footpaths need periodic maintenance to keep them in a usable condition. There is a range of different maintenance techniques available.
Road and Footpath Improvements
In order of cost, with cheapest first:
Localised patch repairs corrects areas that have cracked or crazed but which are structurally sound.
Surface-dressing (a thin layer of chippings spread onto a film of bitumen) protects an otherwise structurally sound and regular surface from water ingress, UV light, slows-down the rate of wear and restores grip.
Find out more about Surface Dressing
Resurfacing corrects the unevenness of a deformed surface or areas of extensive shallow cracking where the integrity of the underlying road is sound.
Localised full-depth repairs (of more than one of the structural layers of the road or footpath) strengthens the road or footpath in areas that have failed through settlement, typically at road edges (known as ‘Haunching’).
Major Maintenance uses a combination of two or more of the above techniques
Drainage improvements allow water, that would normally ‘pond’ on the highway (known as ‘standing’ water), to drain into the drainage system or onto lower ground. Standing water can undermine the road and footpaths’ ability to withstand heavy traffic and cause aquaplaning or the formation of black ice in cold conditions.
As a general rule:
Once a surface starts to become polished, cracked or crazed (damp but drying surfaces show this best), a small amount of localised patch repair (maximum of 5% of the surface area) can be used to deal with any defects. The whole area can then be surface dressed. This approach can delay the need for costly and disruptive major maintenance for upwards of ten to fifteen years.
Where levels of patching exceed 10% of the surface area, it is more than likely that full resurfacing would be a more cost-effective solution.
With problems such as large cracks, extensive potholing and rutting, the only appropriate treatment is localised full-depth repairs.
It is not unusual to find some sites that rate too high for surface dressing but not high enough for resurfacing. The amount of patching required on these site means that surface dressing would not be a cost effective solution. In these circumstances the road must remain untreated until resurfacing can be justified.