Highway development has been a critical part of ARC’s core mission since 1965, when Congress authorized the construction of the Appalachian Development Highway System (ADHS), a 3,090-mile network of highways throughout Appalachia. Since then, ADHS’s 33 corridors have continued to provide access to regional and national markets, contributing to growth opportunities and improved access in Appalachia.
ADHS Completion Status
As of fiscal year 2025, 2,846 miles, or 92.1 percent, of the ADHS is under construction or open to traffic. Three states—Mississippi, New York, and South Carolina—have completed their corridors.
Cost-to-Complete Estimate
In cooperation with the Federal Highway Administration and state departments of transportation, ARC regularly updates the cost-to-complete estimates for the unfinished Appalachian Development Highway System (ADHS) corridors. Based on the 2025 ADHS cost-to-complete estimate, the amount of funds needed to complete all unfinished ADHS corridors is $14.4 billion.
Economic Impact
The construction of the ADHS has increased economic activity across the region, including job creation, worker income, business sales, and saved travel time. According to a 2017 analysis, more than 168,000 jobs were created or maintained due to increased economic activity associated with the ADHS, while $9 billion was added to the gross regional product.
The ADHS also saves 231 million hours of travel time annually. Completion of the ADHS is estimated to create 47,000 more jobs and add $8.7 billion in goods and services annually across Appalachia’s 13 states.
