Traffic Sound & Noise Studies

AGI staff has prepared numerous studies involving traffic noise for developers and public agencies.  Studies have been prepared throughout the United States and a partial list of Projects follows:

Summerlin Parkway Widening Project in Las Vegas, Nevada

AGI staff conducted a traffic noise impact and abatement study for the Summerlin Parkway Widening Project in Las Vegas, Nevada. The 7-mile project included community interface, noise monitoring, traffic noise modeling, and report preparation.  Because the project is a high profile, controversial assignment, AGI staff assisted the design team in community workshops for project and soundwall presentation.  Soundwalls were recommended in the noise study to reduce traffic noise levels to meet NDOT noise criteria.

Route 215 Bruce Woodbury Beltway in Las Vegas, Nevada

AGI staff prepared traffic noise analysis for the 215 Beltway widening project in Clark County, Las Vegas, Nevada. The tasks conducted for this project included community interface, noise monitoring, traffic noise modeling, and report preparation.  Because the project is a high profile, controversial assignment, AGI staff assisted the design team in community workshops for project and soundwall presentation.

Dennis Road Extension in Fairbanks, Alaska

AGI staff conducted a traffic noise study for the Alaska Department of Transportation to evaluate traffic noise impacts from the Dennis Road Extension Project.  The study focused on establishing baseline noise conditions in a rural environment and predicting traffic noise levels for future forecast traffic conditions using the latest version of the FHWA’s TNM model.  A comprehensive noise study was prepared that summarized the results for inclusion into the Environmental Assessment Report.

TCA SR-241 Noise Study in County of Orange

AGI staff completed a traffic noise study for the Transportation Corridor Agency SR-241 Roadway Widening Project in Orange County. The purpose of the study was to evaluate the noise impact associated with roadway widening. Residential receptors located on both sides of SR241, between Bake Parkway and Melinda Road Bridge were the primary focus of the noise study. AGI staff met with TCA sub-consultants to identify key locations as part of the kick-off meeting. The noise study included noise monitoring, and traffic noise analyses using Caltrans’ Sound2000 prediction model. Impacts were assessed based on Caltrans NAC and the results for study were summarized in a noise study report.

I-15 Reconstruction in Salt Lake City, Utah

Over 10 noise studies were prepared to address traffic noise impacts associated with the I-15 reconstruction in Salt Lake City, Utah. Noise studies were prepared to evaluate over 10 segments of the proposed new roadway. For each noise study, noise measurements were conducted and an analysis was performed on the proposed new alignment. Soundwalls were recommended at over 20 locations to mitigate the noise increases associated with the project. The soundwalls were analyzed using a version of the FHWA model STAMINA and the Utah Department of Transportation (UDOT) noise criteria. All recommended soundwalls achieved at least 5 dB of noise reduction and provided noise abatement for numerous communities, schools and churches located along the project’s new alignment. Public hearings, community meetings, and open houses were initiated and held to encourage public participation and opinions.

Mount Highland Drive Soundwall Studies in Butte, Montana

Two noise technical studies were prepared to evaluate the existing and future noise impact associated with the Mount Highland Drive project in Butte, Montana. Ambient noise measurements were conducted to establish baseline conditions. Future noise impacts were predicted with the STAMINA traffic noise model. The noise impacts at residential receptor locations were assessed and noise abatement in the form of sound walls was evaluated to reduce future traffic noise impacts.

Outer Loop Highway Section 13 Noise Study in Phoenix, Arizona

The Outer Loop Highway (OLH) is a 52-mile multi-lane highway which will form a complete loop around the Phoenix metropolitan area. Section 13 of the OLH is centered around the intersection with the Superstition Freeway/SR360. The project involved assessing the impact of traffic noise generated by alternative configurations of the OLH interchange and recommending the location and height of sound walls to meet FHWA requirements. The alternative interchange configurations included tunneled ramps and multiple loop ramp alignments. A version of the Federal highway noise prediction model STAMINA was used for all noise computations. A detailed analysis was conducted for specific receptors to evaluate the benefit from double barriers.

Mountain View Avenue Roadway Widening Traffic Noise Study in Loma Linda, California

AGI staff conducted a traffic noise study for the City of Loma Linda’s widening of Mountain View Avenue. The study limits were from Prospect Avenue north to Van Leuwen Street. AGI staff met with Caltrans and the City of Loma Linda Public Works Department to kick-off the project and to identify key receptor locations. The noise study included ambient monitoring of existing traffic noise and rail noise, and future traffic noise modeling using Caltrans’ Sound2000 traffic noise model. The results of the analyses and impact assessment were summarized into a noise study report.

Washington Street Sound Attenuation Study in the City of La Quinta

AGI staff conducted a soundwall study for the City of La Quinta to evaluate existing and future traffic noise along Washington Street. The study limits were from Avenue 48 to Avenue 50. The noise study included traffic noise monitoring, exterior-to-interior noise monitoring, and verification of compliance for an existing soundwall. Noise abatement measures were evaluated as well as the associated costs. The results for were summarized in a noise study report presented to city staff and Council.

East Chapman Avenue Noise Study in City of Orange, California

AGI staff conducted a noise study for the City of Orange Public Works Department to address existing and future traffic noise and vibration on East Chapman Avenue. The study area was divided into three segments with each segment being treated as an individual subproject. AGI staff met with homeowners to discuss project goals, plans and schedule. The noise study included noise monitoring, exterior-to-interior noise monitoring, and vibration monitoring. Noise abatement measures were evaluated, costs were estimated, and the results were summarized into a comprehensive study for City Council.

San Joaquin Hills Transportation Corridor in Orange County, California

The San Joaquin Hills Transportation Corridor (SJHTC) is the extension of the State Route 73 Freeway from the I-5 freeway in the City of San Juan Capistrano to Jamboree Road in the City of Newport Beach. The project provides three general purpose lanes in each direction, two reversible HOV lanes, a toll system, and the reservation of an 88-foot median for additional capacity as warranted. The corridor is one of the first toll roads in the State of California and passes through the cities of Irvine, Laguna Hills, and unincorporated areas of Orange County. The purpose of the noise study was to assess the future noise impacts for the proposed project and recommend mitigation measures to comply with FHWA and CalTrans noise abatement criteria. Detailed barrier designs and analyses for various sensitive receptors along the corridor based on the specific topography and condition of each receptor was performed. Specifications were developed for the soundwall engineers and design drawings were reviewed for accuracy. Indoor/outdoor noise measurements were conducted for selected houses and building acoustical treatment measures were recommended to mitigate noise impacts. Public hearings, community meetings, and open houses were held to encourage public participation and opinions.

Route 55 Soundwalls in Orange, California

The 55 Freeway is a major freeway serving Orange County with residential properties bordering the freeway right-of-way. A noise study was performed to determine the need for soundwalls along the roadway to reduce or abate traffic noise levels at sensitive locations. Extensive noise monitoring was conducted at residential receptors bordering the freeway. The topography included at grade, above grade, and recessed properties. Analysis was performed to determine the soundwall heights needed to abate traffic noise levels per CalTrans requirements. These soundwalls were ultimately constructed of concrete block with heights ranging up to 16-feet.

91 Freeway Soundwall Study in Anaheim, California

A soundwall study was conducted for the 91 Freeway to address traffic noise impacts at sensitive receptors along the corridor. Noise surveys were performed to quantify existing traffic noise levels at key residential locations. The majority of residences were at grade with the roadway. However, a few receptors were above the freeway roadway elevation. The analysis was performed with CalTrans’ Sound32 traffic noise model. Traffic noise impacts were predicted and noise abatement in the form of freeway soundwalls was recommended.

Bastanchury Road in Fullerton, California

Bastanchury Road is a major arterial serving the City of Fullerton. The roadway is bordered by residential and horse properties on the north and south sides. As part of the environmental documentation, a noise study was performed to quantify existing and future noise levels from the proposed widening of the roadway. Residences located on either side of the road would experience increased noise levels from the widening of the roadway. Noise measurements were conducted in the residential neighborhood to quantify existing sound levels from traffic and background sources. The FHWA noise model was used to predict future noise levels from the widened roadway. Impacts were identified with respect to the local noise standards. Alternative noise control measures were recommended to reduce the traffic noise to acceptable levels.

Route 74 Project in Riverside County, California

This project proposed the widening of State Route 74 between the Interstate 15 interchange in the City of Lake Elsinore and 7th Street in the City of Perris. The entire length of the project was about 8.5 miles. The purpose of the noise study was to assess the environmental impact of highway traffic noise generated by the proposed project on sensitive receptors and recommend mitigation measures to reduce the noise impact based on noise barrier design requirements of the Federal Highway Administration (FHWA) and CalTrans noise abatement criteria. Future noise levels were predicted for the alternative which produces the highest noise levels using the forecasted Level-of-Service ‘C’ traffic for the future design year. Workshops were held with the public to address the impact of the project and noise control alternatives.

Route 85 Soundwall Study in Santa Clara County, California

A noise study was initiated by the Santa Clara Traffic Authority for the Route 85 transportation corridor. This corridor is about 18-miles long and extends from the U.S. Route 101 Freeway in south San Jose to Interstate Route 280 in Cupertino. The project involved assessing the impact of traffic noise generated by Route 85 and recommending preferred location and height of sound walls to meet CalTrans and FHWA requirements. The CalTrans preferred highway noise prediction computer model Sound32 was used for all noise computations. In addition, a detailed analysis was conducted for selected neighborhoods to evaluate reflected noise from soundwalls and underpasses.