Some types of roadways are functionally classified, designed, and regulated with the needs of high-speed through-traffic in mind. The vast majority of roadways are local urban streets or local rural roads; they provide little service to through traffic and essentially provide low-speed access to adjacent and nearby properties. Most access-related conflicts tend to occur on routes that must provide a mixture of service to through-traffic and access to property. Generally, these routes are functionally classified either as arterials or collectors in the United States. Access management involves careful planning and management of direct access (through the public road system or private driveways) to the arterial and collector roadway systems. This is done through a variety of treatments and standards, including driveway spacing standards, driveway corner clearance standards, and the installation of raised medians. Retrofit access management projects are generally planned and implemented on a corridor by corridor basis. This paper suggests a strategic approach to access management in an urban area. Geographic information systems (GIS) along with road inventory data, safety management data, land use planning information, and aerial photography are used to identify priority corridors for access management in the Ames, Iowa area. The results are then compared with those of a citizen survey of arterial routes that city residents would most like to have improved. The results from the GIS analysis and the citizen survey are nearly identical in the case of Ames, suggesting that the city could expect considerable support (from residents, at least) for an aggressive access management program. (a)
Samenvatting