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Safe, Accountable, Flexible, Efficient Transportation Equity Act: A Legacy for Users (SAFETEA-LU)

Fact Sheets on Highway Provisions


Year 2005 2006 2007 2008 2009
Authorization* $4,884M $4,961M $5,039M $5,119M $5,199M
*Authorizations shown here will be augmented by a portion of the Equity Bonus Program funds

Program Purpose

The Interstate Maintenance (IM) program provides funding for resurfacing, restoring, rehabilitating and reconstructing (4R) most routes on the Interstate System.

Statutory References

SAFETEA-LU Section(s): 1101(a)(1), 1111

Other: 23 USC 119, 104(b)(4), 118(c)


Funded by contract authority, to remain available for 4 years. Funds are subject to the overall Federal-aid obligation limitation. A State may transfer up to 50% of its IM apportionment to its National Highway System, Surface Transportation, Congestion Mitigation and Air Quality Improvement, Highway Bridge Replacement and Rehabilitation, or Recreational Trails apportionment.

The following funds are to be set aside from the authorized amounts:

Interstate Maintenance Discretionary

$100 million for each fiscal year 2005 through 2009 to be distributed at the discretion of the Secretary of Transportation for projects for 4R work (including added lanes) on any route or portion thereof on the Interstate System. Excluded are projects on any highway designated as a part of the Interstate System under 23 USC 139 as in effect before the date of enactment of TEA-21 and any toll road on the Interstate System not subject to an agreement under 23 USC 119(c) as in effect on December 17, 1991. Funds are available until expended. [1111(a), 23 USC 118(c)]

Funds are apportioned to States based on the following factors:

  • 33-1/3% based on lane miles on Interstate System routes open to traffic
  • 33-1/3% based on total vehicle miles traveled on Interstate System routes open to traffic
  • 33-1/3% based on State's annual contributions to the Highway Account of the Highway Trust Fund attributable to commercial vehicles.

Each State shall receive a minimum of ½ percent of combined IM and National Highway System apportionments.

Eligible Use of Funds

Projects on routes on the Interstate System, except those added under 23 USC 103(c)(4)(A) that were not previously designated future Interstate under former 23 UCS 139(b), as well as any segments that become part of the Interstate System under Section 1105(e)(5) of ISTEA are eligible for funding. Construction of additional Single Occupancy Vehicle (SOV) lanes continues to be ineligible for IM program funds.

IM program funds may not be used on a facility where tolls are being collected under the Interstate System Reconstruction and Rehabilitation Pilot Program [TEA-21 1216(b)] or the Interstate System Construction Toll Pilot Program. [1604(c)(7)]

Federal Share

The Federal share is 90 percent, subject to the sliding scale adjustment. Certain safety improvements listed in 23 USC 120(c) have a Federal share of 100 percent.

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