The pavement overlay program provides a new pavement surface on existing streets that have deteriorated to a condition that chip sealing is not an acceptable treatment. The overlay process involves many activities. Prior to the actual overlay taking place, patching, utility adjustment, traffic signal actuators, and mandated American Disability Act (ADA) access ramp improvements need to be completed.
Most overlay projects include milling off a portion of the existing pavement surface, placement of a geo-textile paving fabric, and the application of a new asphalt pavement surface. This new asphalt surface is normally two to four inches thick. Collector and arterial streets require new striping with this kind of maintenance treatment. During the process, utility adjustments for manholes and water valve boxes are also required. Each street in the overlay process is evaluated for the type of overlay it will receive. These factors include traffic types and amounts, existing surface condition, and structural strength.
In some cases, a total or partial reconstruction needs to take place when a street has completely failed and even an overlay is not applicable. Pavement reconstruction involves all the aspects of a mill and overlay, except the pavement and base are totally removed, the underlying sub-grade soils are repaired and re-compacted, new base coarse material is constructed, and a total new pavement structure is constructed.