Summary: Thirty-six state and two federal agencies have recognized 34,000 miles of roads as scenic byways--roadways that provide access to historic, cultural, recreational, and other resources. Many of these roads were built years ago, often to specifications that fall short of today's geometric design standards governing the physical layout of roads. In relying on current standards to improve or reconstruct their scenic byways, state highway agencies could end up damaging the byway's scenic character because the standards emphasize mobility and safety rather than preservation. To help prevent such damage, Congress passed legislation giving state highway agencies the flexibility to apply alternative to the geometric design standards for improving and reconstructing scenic byways. This report discusses (1) what design standards states use or plan to use to improve and reconstruct roads in scenic areas and (2) what national design standards or guidance is available to state for improving and rebuilding such roads. In addition, GAO provides information on design approaches to reconstructing one scenic byway--Rhode Island's Ministerial Road--to illustrate the trade-offs involved in different design standards.
