Traffic Data Collection, Reduction and Dissemination Program Needs Assessment

Traffic monitoring is defined by the American Society for Testing and Materials (ASTM) designation E-1442 as the "activity of collecting, summarizing and reporting traffic volume, vehicle classification, and vehicle weight data". This comprises of three major elements, namely (Traffic Monitoring Guide, 1985): 1. Continuous count (ATR) element 2. Highway Performance Monitoring System (HPMS coverage) element a. HPMS sample subelement b. Traffic volume subelement c. Vehicle classification subelement d. Truck weight subelement 3. Special needs element\nNDOT is currently maintaining a traffic monitoring system on its approximately 5,400 miles of road and 3230 count stations. Continuous counts are being performed on its 36 automatic traffic recorders (ATR) which record traffic volume on a continuous hourly basis for a period of one year. Currently, the traffic monitoring year starts from October and ends in September of the following year. Starting 1993, NDOT will perform the annual traffic collection following the calendar year.\nThe magnitude of data collected annually necessitates an efficient way of managing these data and making them available for use, on a timely basis. The present practice of NDOT is to combine both manual and computerized procedures to facilitate traffic data management.\nOne of the biggest problems of the Department deals with data management which includes data editing, storage and access, especially when responding to specific requests from the public. The existing traffic system does not provide easily accessible and readable data.\nDue to the absence of standardized procedures of traffic monitoring in the past, the Department adopts practices which may or may not be similar with other states and may not be generally acceptable. Manual editing are often performed by the traffic analysts who may follow different procedures of correcting the data. Thus, problems of non-uniformity and inconsistency exist.\nThe nationwide interest towards standardization of procedures started in 1985 through the issuance of the FHWA Traffic Monitoring Guide. This was followed by the ASTM designation E- 1442-91 (Standard Practice for Highway-Traffic Monitoring) and lately, the 1992 AASHTO Guidelines for Traffic Data Programs. The need to evaluate the Department traffic monitoring system becomes more relevant with the development of these standards.