The 1991 Intermodal Surface Transportation Efficiency Act (ISTEA) established 21 high priority corridors on the National Highway System (NHS). The purpose of establishing these corridors of national significance was to allow the Secretary of Transportation, in cooperation with the States, to prepare long-range plans and feasibility studies and to allow the States to give priority to funding the construction of these corridors and to provide increased funding for segments of these corridors that have been identified for construction. This created a new discretionary funding category for the conduct of feasibility and design studies.
Congress used the following reasons for creating the high priority corridors:
a) The construction of the Interstate Highway System connected the major population centers of the Nation and greatly enhanced economic growth in the United States.
b) Many Regions of the Nation are not now adequately served by the Interstate System or comparable highways and require further highway development in order to serve the travel and economic development needs of the region.
c) The development of transportation corridors is the most efficient and effective way of integrating regions and improving efficiency and safety of commerce and travel and further promoting economic development.
In 1995, the National Highway System Designation Act amended Section 1105 (c) (3) of ISTEA and in Kentucky listed I-66 as centered on the cities of Pikeville, Jenkins, Hazard, London, Somerset, Columbia, Bowling Green, Hopkinsville, Benton and Paducah. The Southern Kentucky Corridor (I-66) would connect with the proposed King Coal Highway (also called I-73 / 74 North-South Corridor) in West Virginia as listed in Section 1105 (c) (5) in ISTEA (1991).
Governor Paul E. Patton of Kentucky is actively pursuing a strategic development plan for Appalachian Kentucky. The plan premise is that Kentucky cannot advance as a Commonwealth if any sections of the state lag in socioeconomic development. The Governor's plan focuses on preparing Appalachian communities to host commercial activities and processes that will fuel economic development and lead to local sustainable economies. Effective preparation is linked to a number of factors, one of which includes building adequate infrastructure such as a highway system to enhance a community's posture as a site for sustainable economic development.
A number of studies have been completed on the Southern Kentucky Corridor (I-66) and proposed King Coal Highway. For the SOUTHERN KENTUCKY CORRIDOR (I-66), the Trans American Corridor Location Study was completed in 1994, while a Study Approach and Issues, Existing Conditions, Project Cost Estimate, Economic Impact Assessment, Economic Justification and Financial Feasibility Study, and a Corridor and Need Study and Feasibility Study were completed in 1994.