The purpose of the corridor study is to determine the best way to serve existing and future travel demand. These studies bring together the goals and expectations of all groups involved in the project. Corridor studies typically respond to a specific problem (high accident locations and corridors, high levels of existing or future congestion, significant land-use changes, etc.) and often involve more than one mode. These studies identify existing and future deficiencies and evaluate alternative solutions. The recommended alternative usually includes a facility description including environmental, operational, and other impacts (with proposed mitigation, if applicable). Corridor planning is accomplished using a long-range outlook (at least 20 years).
These studies may be broad in purpose and recommendations. On the other side of the spectrum, they may be very specific, providing a significant level of detail, for a specific purpose.
Typically an existing facility, such as a highway or a rail line, will define the axis of the corridor. The corridor may often extend beyond the facility right-of-way. Sometimes the corridor may be narrow, but it may be as much or more than five miles on either side of the axis. The length of the corridor will usually connect major destinations, such as two cities, or a major portion of the distance between those destinations. A corridor may also cover the length of an entire route.
Corridors may be defined in terms of broad geographic areas served by various transportation systems. These systems provide important connections between various regions for passengers, goods and services. Studies of this magnitude might be defined in such terms as “Regional or Mega-Corridors” and address linking of facilities and systems (such as rail, highway, transit lines, transit stations, bicycle paths, airports and marine ports/terminals) with a network of these links, services and facilities. These other locations would represent readily understandable corridor beginning and end points, referred to as logical termini.
The Transportation Research Board has provided guidelines in developing corridor studies in The National Cooperative Highway Research Program, Report 435, “Guidebook for Transportation Corridor Studies: A Process for Effective Decision-Making”. In addition to discussing the steps of the planning process for corridor studies, the guidebook deals with the decision-making process and its relationship to the National Environmental Policy Act. The guidebook recommends development of core competencies to enable these studies to be conducted in-house. It recommends training for the following core competencies: modeling, public involvement and consensus building, economic analysis, financial analysis and funding.
Benefits of corridor planning include:
• Resolution of major planning issues prior to the initiation of project development
• Identification and possibly preservation of transportation right-of-way
• Protection of transportation investments
• Partnerships with diverse public and private agencies and organizations
The National Cooperative Highway Research Program (NCHRP) was created in 1962 as a means to conduct research in acute problem areas that affect highway planning, design, construction, operation, and maintenance nationwide. The NCHRP is administered by the Transportation Research Board and sponsored by the member departments (i.e., individual state departments of transportation) of the American Association of State Highway and Transportation Officials, in cooperation with the Federal Highway Administration.