FHWA Proposes Revisions to Procedures for Traffic Noise Abatement

10.13.2009 | HMMH |

by Doug Barrett

On September 17, the Federal Highway Administration (FHWA)issued a notice of proposed rulemaking (NPRM) and request for comments related to 23 CFR Part 772.  For those involved with traffic noise analysis, 23 CFR Part 772 is the source from which all other state or local guidance flows.  While maintaining much of the existing regulation, the proposed changes would provide many clarifications, as well as some new additions and other changes that may influence traffic noise studies for many years to come.

Highway Traffic

First, a little background information for those not familiar with 23 CFR Part 772.  This portion of the Code of Federal Regulations addresses “Procedures for Abatement of Highway Traffic Noise and Construction Noise” and provides the basis for State transportation agency noise abatement standards in use throughout the U.S.  The regulation, originally developed as a requirement of the Federal-Aid Highway Act of 1970, applies to highway construction projects where a State department of transportation has requested federal funding for the project.  The FHWA provided further clarification and guidance in the 1995 document “Highway Traffic Noise Analysis and Abatement Policy and Guidance.”   While updating the 1995 document, the FHWA determined that certain changes to 23 CFR Part 772 were necessary.

The current NPRM proposes numerous changes to the existing regulation.  While soliciting comments on all the proposed changes, the FHWA is specifically seeking comments on three additions to the regulation:

  • The first would require highway agencies to determine a baseline cost-reasonableness value.  This value, which would require FHWA approval, may include the actual construction cost of noise abatement, cost per square foot of abatement, and either the cost per benefited receiver or cost per benefited receiver per dB(A) noise reduction.  In addition, highway agencies would be required to reevaluate these costs at least every five years.
  • The second addition would provide a change from past FHWA guidance regarding when third parties may contribute additional funds to a noise abatement measure or aesthetic treatment.  The NPRM would allow third party contributions only after the highway agency has determined that the noise abatement measure is feasible and reasonable.
  • The third addition would require each highway agency to maintain an inventory of all constructed noise abatement measures.

Other portions of the NPRM provide definitions or clarification of terms included either in the current regulation or in the 1995 policy document.  For example:

  • “Residence” would be defined to include all dwelling units, e.g., owner-occupied, rental units, and mobile homes.  In addition, “multi-family dwelling” would be defined.
  • “Special land use facilities” would be defined and would include picnic areas, recreation areas, playgrounds, active sport areas, parks, motels, hotels, schools, places of worship, libraries, hospitals, cemeteries, campgrounds, trails, and trail crossings.
  • The terms “planned, designed, and programmed” and “date of public knowledge” would be defined to clarify the cut-off date for considering new residential construction for noise abatement.
  • “Severe noise impact” would be defined.  Areas meeting this definition may be eligible for (1) exterior noise abatement that exceeds the allowable cost for feasible and reasonable abatement measures, or for (2) consideration of interior noise insulation for privately owned structures.
  • States would be required to define a “Substantial increase” criterion that is between 10 and 15 dBA over existing noise levels.
  • “Benefited” receptors must recieve “at least 5 dBA reduction” and benefited recievers must be included in determining cost reasonableness, even if not impacted.
  • The noise analysis study area would be required to extend at least 500 feet from all termini of the project build alternatives.

The NPRM also would require highway agencies choosing to participate in a Type II (retrofit) noise barrier program to develop an FHWA-approved priority system, based on a variety of factors, and rank the projects.  While some state agencies currently employ system-wide prioritization lists (HMMH has assisted the Massachusetts Turnpike Authority, the District of Columbia, and the New York State Thruway Authority in the development of their Type II prioritization lists), others currently construct Type II barriers based on ad hoc funding made available on a project by project basis.

This is a summary of only some of the proposed changes.  The full NPRM is available at  Comments on the NPRM must be received by November 16, 2009 and may be submitted via the Federal eRulemaking Portal.