Pembrokeshire County Council's area maintenance works division is due to start its annual road surface-dressing programme from the end of this week, in two separate operations.
The first, in the south, starts from Angle and works towards Dale, via Tenby, Narberth and Haverfordwest. The second operation commences in St. Davids and heads towards St. Dogmaels in the north of the county.
Surface dressing involves a coating of bitumen being sprayed onto the road surface, followed by one or more layers of hard stone chippings. Once the dressing has settled down after two or three days, the surplus chippings are then swept up by a mechanical sweeper.
Good reasons for carrying out the operation are that it restores a good skid resistance to smooth or slippery roads, prevents water from seeping into the road foundation and weakening it, thus reducing the chances of potholes developing and therefore delaying the need for complete rebuilding of a road. It is up to ten times cheaper than other methods of restoring road surfaces and allows traffic to run on the new surface almost immediately, avoiding lengthy closures and disruption.
The disadvantages are that drivers need to travel very slowly on the newly-laid surface to prevent chippings being dislodged, inconsiderate drivers travelling above the recommended speed cause chippings to be thrown up which can damage other vehicles and property.
To be successful, surface dressing relies on warm dry weather and for this reason work is carried out from May to September. This ensures that physical changes to the bitumen take place and that the chippings become embedded into the road surface, which ensures long term stability of the new surface.
Pembrokeshire County Council will, where practicable, give advance notice of works to residents and drivers and provide advisory and warning signs from the time of treatment to the time the road is ready for normal use.
The council will sweep the road of surplus chippings once the new surface has settled down and ensure that surface dressing is carried out to a high standard.
The authority will also minimise hazards and disruption to traffic through correct use of traffic control and ensure that complaints are investigated and appropriate action taken.
Motorists are asked to ensure their vehicle is not left on the road to be treated, drive carefully to the recommended speed limit on recently treated roads, or when signs are displayed, never overtake, and avoid sudden braking and turning on newly treated roads.
Pedestrians are warned to take care walking near newly treated surfaces, as it is possible to get bitumen on shoes. This can be easily removed by the use of solvents such as turpentine or white spirit.