Case Study

Road: Highway Air Quality Analysis (US)

The project, conducted for a Department of Transport,  is one of the largest transportation projects in the State. The Bypass is a proposed new 11-mile, 4-lane access controlled expressway to go around the a number of cities in the County. The Bypass is needed to reduce congestion.







Project Objectives:

SLR is performing the Noise and Air Quality analyses to fulfill National Environmental Protection Act (NEPA) requirements for the final Environmental Impact Statement (EIS) as required by the Federal Highway Administration (FHWA). The noise analysis has been complex because the new 4-lane road is proposed through areas not currently significantly impacted by traffic noise and due to the projects complex topography. The analysis was also complicated by the planned construction of the project in two phases, requiring additional noise analysis for the Phase 1 improvements. The noise analysis must be reviewed and approved by our client and the FHWA. The EIS was published in Spring 2012.

Our Role

SLR undertook the following works:

•Performed the Noise Analyses and Air Quality to fulfill NEPA
•The noise analysis must be reviewed and approved by our client and the FHWA
•Extensive detailed modelling using the FHWA Traffic Noise Model
•Complex analysis of potentially feasible noise mitigation measures
•Historical structure noise analysis
•Results of analyses used to establish “noise impact zones”
•The EIS was published in Spring 2012