Federal-Aid Highway Program Guidance on High Occupancy Vehicle (HOV) Lanes
August 2008
Appendix B
A Summary of 23 U.S.C. 166 Requirements for Exceptions to Minimum Occupancy Requirements
States are provided flexibility in 23 U.S.C. 166 to maximize the throughput of HOV facilities by allowing exempted vehicles to use excess capacity. The information contained in this appendix summarizes the requirements found in 23 U.S.C. 166 for vehicles that do not meet the minimum occupancy requirement to use HOV lanes.
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Motorcycles and Bicycles 23 U.S.C. 166(b)(2) | SOV Public Transportation Vehicles 23 U.S.C. 166(b)(3) | High Occupancy Toll Vehicles 23 U.S.C. 166(b)(4) | Inherently Low Emission Vehicles 23 U.S.C. 166(b)(5) | Low Emission and Energy-Efficient Vehicles and Alternative Fuel Vehicles 23 U.S.C. 166(b)(5) |
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Access to HOV Facilities | Mandatory unless a State certifies to FHWA that these vehicles would create safety hazard. | Optional if excess capacity is available. | Optional if excess capacity is available. | Optional if excess capacity is available. | Optional if excess capacity is available. |
Requirements for certifications before allowing exceptions to use HOV facilities | No. Only if a State wants to prohibit these vehicles to use HOV facilities due to safety hazards. | Optional but States are encouraged to work with local FHWA Division Offices in submitting certifications before allowing exceptions to use HOV facilities. | Optional but States are encouraged to work with local FHWA Division Offices in submitting certifications before allowing exceptions to use HOV facilities. | Optional but States are encouraged to work with local FHWA Division Offices in submitting certifications before allowing exceptions to use HOV facilities. | Optional but States are encouraged to work with local FHWA Division Offices in submitting certifications before allowing exceptions to use HOV facilities. |
Required to submit annual certification | Optional | Optional | Yes | Yes | Yes |
Requirements for performance monitoring | Optional | Optional | Yes | Yes | Yes |
Requirements for enforcement | Optional | Yes | Yes | Yes | Yes |
Limit or discontinue the use of the HOV facility if the presence of these vehicles has degraded the operation of the facility | No | Optional | Yes, but in no particular order. | Yes, but in no particular order. | Yes, but in no particular order. |
Requirements for labeling | No | Yes | Yes | Yes | Yes |
Subject to be tolled | No | No. However, decision to implement 166(b)(3) is discretionary. If State implements HOT Lane under 166(b)(4), SOV public transportation vehicle may be tolled as a HOT vehicle. | Yes | Optional | Optional |
Requirements for automatic toll collection | N/A | N/A | Yes | No | No |
Toll agreement | N/A | N/A | Yes | Yes, unless no toll is charged. | Yes, unless no toll is charged. |
Requirement to manage demand by varying toll amounts | N/A | N/A | Yes | No | No |
Use of toll revenue | N/A | N/A | Debt Service, reasonable return on investment, operations and maintenance of toll facility. | Debt Service, reasonable return on investment, operations and maintenance of toll facility. | Debt Service, reasonable return on investment, operations and maintenance of toll facility. |
Use of excess toll revenue | N/A | N/A | Must be eligible under Title 23 and give priority to projects for developing alternative to SOV travel and projects for improving highway safety. | Must be eligible under Title 23 and give priority to projects for developing alternative to SOV travel and projects for improving highway safety. | Must be eligible under Title 23 and give priority to projects for developing alternatives to SOV travel and projects for improving highway safety. |