Local Road Management Manual 203 markets and government services, as well as the general mobility of people and goods. Hence, there is a need to preserve and properly manage these assets if the beneifts from the use of the road are to be sustained. Road assets can be preserved and managed through the timely implementation of routine and periodic maintenance. Without such interventions, road assets will result to deterioration, reduced usability of the road, and high costs for reconstructing failed sections (maintenance costs is signiifcantly less expensive than new construction or rehabilitation). Damage as a result of lack of maintenance will mean reduced beneifts and higher travel cost to road users. Deteriorated roads will increase vehicle operating costs due to frequent repairs and higher fuel consumption, which would then discourage or would act as disincentives for transport operators to provide service to passengers and to carry goods from production area to the market. The American Association of State and Highway Transport Oiffcials (AASHTO) deifnes the service life cycle of a road as: a. Design. This stage deals with dimensions, type of materials, thickness of base and top surfaces, and the drainage system. Investments made at the design stage affect the long-term durability of the pavement surface. If, however, suiffcient funding is not available to upgrade the design, the road starts out and stays mediocre; b. Construction. A high-quality construction process produces a longer-lasting pavement surface; c. Initial Deterioration. During the ifrst few years of use, the road surface starts to experience some initial deterioration caused by traiffc volume, rain, snow, solar radiation, and temperature changes. At this stage, the road appears in good condition, providing a smooth ride. Preservation strategies at this stage will sustain the smooth ride, preserve the foundation, extend the life, and reduce the need for costly reconstruction later on; d. Visible Deterioration. Visible signs of distress such as potholes and cracking occur. Repairs made at this stage using overlays and milling to eliminate ruts will restore a smooth ride and extend the life of the road; and