Oak Tree Road over Conrail Lehigh Valley Line Bridge Replacement

Project Description

The Oak Tree Road over the Conrail Lehigh Valley line bridge is structurally deficient and functionally obsolete; therefore, the NJDOT will replace the bridge to meet current geometric and safety standards. Proposed improvements include a six-foot wide sidewalk on both the north and south sides of the bridge, an increase in the bridge elevation to meet the 23-foot vertical under clearance over the Conrail tracks and 35 mile per hour design speed, as well as a westward shift in the bridge alignment to minimize property impacts to the east. One commercial/residential structure along westbound Oak Tree Road will be required to accommodate the proposed improvements.

The significant vertical change to both the structure and roadway profile would be considered a Type I improvement, as defined within 23 CFR 772.5; therefore, PCA performed a quantitative traffic noise assessment detailed within a Noise Assessment document and summarized within the NEPA Categorical Exclusion Document (CED) prepared for the project. The traffic noise assessment was performed pursuant to 23 CFR 772 and in accordance with NJDOT’s Traffic Noise Policy. Existing noise measurements with concurrent vehicle classification counts were conducted in two locations to validate the project-specific TNM2.5 model. Since noise measurements were conducted in 2021 when schools in the region were operating partially remotely due to the on-going COVID-19 pandemic, concurrent 2021 traffic counts obtained during noise measurements were compared with historic (2017) traffic counts, which were projected to 2021 using a NJDOT approved growth rate. Projected volumes were higher for all movements; therefore, the grown 2021 traffic volumes were conservatively used within the project-specific TNM2.5 model to evaluate existing conditions. Projected 2021 traffic volumes based on pre-pandemic traffic conditions were subsequently grown to 2045 to evaluate No Build and Build condition noise levels. Noise impacts were predicted at residences along Oak Tree Road with direct access/driveways to/from Oak Tree Road; therefore, noise walls would not be acoustically feasible due to the gaps necessary to maintain access to intersection roads and driveways.