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Vertical Clearances - Highway Development and Coordination with Other Agencies

Formerly Federal-aid Policy Guide Non-Regulatory Supplement NS 23 CFR, Part 620A,
December 9, 1991, Transmittal 1
See Order 1321.1C FHWA Directives Management

  1. Policy (23 CFR 620.103)
    1. Further, the FHWA encourages all highway and airport agencies to cooperate to achieve safety and economy in highway and airport development and operation.
    2. Any case, in which airway-highway clearance conflicts cannot be resolved by cooperative agreement at the field level, shall be referred through the Regional Federal Highway Administrator, with recommendations, to the Federal Highway Administrator.
  2. STANDARDS (23 CFR 620.104). Part 77 of the Federal Aviation Regulations, or amendments thereto, are the basic criteria to be applied at public-use and military airports. These standards prescribe required vertical clearances over highways and are coordinated between FAA and FHWA at their respective Headquarters.
  3. Coordination with FAA (No CFR paragraph reference)
    1. Any proposed Federal-aid highway project to which this directive applies where there may be a potential for substandard airway-highway clearances shall be coordinated with the concerned FAA Airports District Office.
    2. Although programming, A-95, and National Environmental Policy Act (NEPA) requirements will usually identify potential conflicts, such requirements do not guarantee the avoidance or resolution of conflicts.
      1. Any Federal-aid highway project within 2 miles of an airport should be carefully examined to determine if there is a possibility for conflict and if coordination is required.
      2. Any highway project on which mobile objects are shielded by existing structures of permanent and substantial character or by natural terrain or topographic features of equal or greater height or which are located more than 2 miles from an airport will, normally, not require coordination.
      3. No coordination is required on those projects which may be considered stage construction of projects previously coordinated and which do not result in increased elevation of critical project elements previously coordinated.
    3. All information submitted by the FAA Airports District Office regarding new public-use airports or changes to existing public-use air ports shall be reviewed by the FHWA to determine if the clearances provided are sufficient. The FHWA shall advise the FAA Airports District Office of its finding and give concurrence that airport construction or extension and any consequent expenditure of Federal funds for the necessary highway reconstruction or relocation are in the public interest.
    4. FAA procedures for coordinating proposed improvements are contained in FAA Order 5000.3.
    5. Federal-aid programming procedures provide for consideration of airway-highway information when an airport is involved. Accordingly, program documentation will furnish a suitable check point to determine if coordination is necessary and if it has been accomplished where required.
  4. Coordination with Military Agencies and Private Air Ports (No CFR paragraph reference). Coordination with military agencies and private airports should make use of guidelines similar to those used for public-use airports. In these cases, the commander in charge of the military airport or the private airport owner will be the coordinating airport official.
Updated: 06/27/2017
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