Preservation: A treatment applied to a road in high fair to good condition that extends the pavement service life without substantially increasing the pavement structure (thickness). Typical pavement preservation treatments include bituminous surface treatments (chip seals), thin lift asphalt overlays, crack sealing, microsurfacing, and diamond grinding on concrete roadways.
Resurfacing: A hot mix asphalt overlay of an existing roadway. Resurfacing may consist of one or two lifts of asphalt surface course and may also consist of milling and replacing asphalt layers, microsurfacing, and other treatments. To minimize cost, a road should be resurfaced prior to the need for significant patching. The maximum thickness of resurfacing is two inches.
Rehabilitation: Significant work done to a road in poor to low fair condition, or to a road requiring additional structure due to increased traffic loads. Rehabilitation frequently includes full-depth patching, leveling, deep milling, or multiple lift overlays.