What we do

We offer expert assistance in transportation and community noise analysis and mitigation as well as transportation air quality assessments. Our work includes highway and rail environmental impact and assessment studies, acoustical design of noise abatement, statewide and regional noise barrier prioritization studies, policy analysis and revision, methods development, and research.

Bowlby & Associates, Inc. also develops and teaches transportation noise courses.  We provide a short course on Traffic Noise Fundamentals and the use of the Federal Highway Administration’s Traffic Noise Model version 2.5 (TNM).  We have delivered that course more than 50 times in the last 20 years including sessions for the state DOTs in California, Georgia, Indiana, Minnesota, and Washington.  Training development clients include the National Highway Institute, USDOT, and New York State DOT. 

Our work also includes:

  • industrial plants
  • rock quarries
  • retail facilities
  • pump stations
  • natural gas regulators
  • construction sites
  • emergency generators
  • HVAC systems
  • noise ordinances
  • racetracks
  • stadiums
  • concerts
  • “soundscapes” for the National Park Service (NPS)

Traffic Noise Analysis and Noise Studies

Bowlby & Associates, Inc. offers expert assistance in transportation and community noise analysis and mitigation. We have completed hundreds of noise studies for federal projects per the FHWA noise regulation, Procedures for Abatement of Highway Traffic Noise and Construction Noise, 23 CFR 772, and state noise policies for an extensive list of DOTs. We have evaluated all types of highway projects, including complex interstate widening and interchange projects, new alignments, widenings, bridge replacements, and truck climbing lanes. We have managed many noise barrier projects from environmental through design and construction. We also perform noise studies to meet the Department of Housing and Urban Development (HUD) requirements per 24 CFR Part 51, Subpart B.

Our experience also includes evaluating noise policies and procedures for state and federal government agencies, assessing noise barrier priorities and needs, determining noise barrier effectiveness, and evaluating tire-pavement noise.

HUD Noise Assessments

We perform environmental noise assessments to meet the U.S. Department of Housing and Urban Development (HUD) requirements per 24 CFR Part 51, Subpart B. HUD permits the use of the Federal Highway Administration’s Traffic Noise Model version 3©® (TNM 3) for assessing roadway noise. This model transcends the HUD Calculator by considering factors like terrain, roadway geometry, and shielding, leading to more accurate noise predictions. TNM 3 often generates lower noise predictions that may eliminate the need for time-consuming Environmental Impact Statements (EIS) and potentially unnecessary noise mitigation measures for some projects.

At B&A, we’ve been at the forefront of TNM expertise. Our team conducted beta testing for TNM 3.2 for FHWA and has provided TNM training for over two decades. Trust our experience and in-depth knowledge of TNM 3 for your HUD noise assessments. Contact us today to discuss your needs.

Rail Noise Studies

Bowlby & Associates, Inc. has conducted noise studies for commuter trains, high-speed rail, and light rail systems including the evaluation of noise abatement. We have also evaluated freight operations and retarders.

Non-transportation Noise Measurement & Analysis

Bowlby & Associates, Inc. has performed noise studies and assessments for varied clients in the private sector including warehouses, metal plants, natural gas regulator stations, hospitals, national parks, restaurants, outdoor amphitheaters, racetracks, and rock quarries.

Research

Bowlby & Associates, Inc. is a leader in the transportation noise research arena. We have been involved in many research studies for FHWA that resulted in FHWA publications including the Noise Measurement Handbook (FHWA-HEP-18-065) and associated Noise Measurement Field Guide (FHWA-HEP-18-066), Noise Barrier Acceptance Criteria: Analysis (FHWA-HEP-16-017); Techniques for Reviewing TNM Model Runs and Associated Noise Modeling Reports (FHWA-HEP-18-068); Techniques for Reviewing Noise Analyses and Associated Noise Reports (FHWA-HEP-18-067); Evaluation of 23 CFR 772 for Opportunities to Establish Programmatic Agreements (FHWA-HEP-17-060); Evaluation of 23 CFR 772 for Opportunities to Streamline the Noise Study Process (FHWA-HEP-17-061).

We were also on the research teams that developed NCHRP Report 791, Supplemental Guidance on the Application of FHWA’s Traffic Noise Model (TNM); NCHRP Report 886, Field Evaluation of Reflected Noise from a Single Noise Barrier, and NCHRP Report 882, How Weather Affects the Noise You Hear from Highways.

Air Quality Studies & Air Pollutant Emissions Analysis

Bowlby & Associates, Inc. performs Air Quality Studies for highway projects, including transportation conformity, CO hot-spot analysis, pollutant emissions assessments, qualitative and quantitative MSATs analysis, and climate change evaluations.