"This manual is an update of the Emergency Relief Manual, Interim Update August 2003. It provides updated guidance and instructions on the Federal Highway Administration's (FHWA) emergency relief (ER) program. This manual provides information for FHWA, State, and local transportation agency personnel on policies and procedures for requesting, obtaining and administering ER funds. This manual covers only those criteria and procedures applicable to the ER program for Federal-aid highways, these being public highways other than those functionally classified as local roads or rural minor collectors. Procedures relating to the ER program for roads on Federal lands that are not Federal-aid highways are outlined in Emergency Relief for Federally Owned Roads (ERFO) Disaster Assistance Manual, Publication Number FHWA-FLH-04-007. […]. Congress authorized in Title 23, United States Code, Section 125, a special program from the Highway Trust Fund for the repair or reconstruction of Federal-aid highways and roads on Federal lands which have suffered serious damage as a result of (1) natural disasters or (2) catastrophic failures from an external cause. This program, commonly referred to as the emergency relief or ER program, supplements the commitment of resources by States, their political subdivisions, or other Federal agencies to help pay for unusually heavy expenses resulting from extraordinary conditions. Examples of natural disasters include floods, hurricanes, earthquakes, tornadoes, tidal waves, severe storms, and landslides. A catastrophic failure is defined as the sudden and complete failure of a major element or segment of the highway system that causes a disastrous impact on transportation services."
United States. Federal Highway Administration: http://www.fhwa.dot.gov/