Chapter 3: Local Road Planning 84 4.2. Level of Service for Local Roads 4.2.1 Local Road Traiffc Volume Traiffc or vehicle volume determines the over-all loading unto the pavement of a local road. It is therefore important to consider the present and future (projected) traiffc volume passing unto a local road. An increase in future traiffc volume will entail necessary design changes for a local road such as geometric conifguration and pavement type. Such design changes should make the local road suiffcient to carry the design traiffc volume without a drop of level of service. Table 3.7 lists down the vehicle classiifcation used in surveying the traiffc volume of a local road. Each vehicle is counted as they pass through a section of a local road. Engineers will often use the number of vehicles passing a point or entering an intersection in the analysis of roadway operations. The two basic methods of collecting data are manual observation and automatic recording. Each has their use and effectiveness depending on the type of information needed for analysis. The traiffc data is the basis of all analysis in a traiffc impact study and careful consideration should be given to the locations, types of counts and duration of counts. This also the basis for the Geometric improvement of a certain road section and for its pavement design. Table 3.7 Vehicle Classiifcation for Traiffc Survey of a Local Road