As part of the Madison County Highway Department’s pavement management program, selected roads throughout the County each year receive a surface treatment sometime between May and September. The Highway Department has found that a program of preventive maintenance using a Bituminous Seal Coat (BSC) treatment, also sometimes referred to as Chip Seal, is the most cost effective way to extend the useful life of the County’s road network. Chip Sealing protects pavements from the damaging effects of water and air infiltration and sunlight exposure that can rapidly deteriorate a road. In many cases the use of this type of surface treatment will eliminate the need to do expensive pavement patching and will add years to the life of the existing pavement.
A single Bituminous Seal Coat (or chip seal) involves spraying liquid asphalt on the pavement followed by the spreading of a layer of small aggregate (rock) that is embedded into the oil. A double chip seal, also referred to as a Double Bituminous Surface Treatment or DBST, is a single chip seal with a second application (layer) of liquid asphalt and small aggregate. Chip seal surface treatment applications are performed by Highway Department maintenance crews.
Prior to the chip seal application, Highway Department maintenance crews will prepare the roads for the surface treatment. The preparation work can include crack sealing, removal/replacement of broken pavement, repairing potholes and repairing road shoulders. Preparation work is typically performed in the fall after the previous year’s surface treatments have been applied and in the spring after the winter weather.