Community Noise Study for Railroad Relocation

A procedure is developed that can be utilized to predict the noise impact of passing freight train cars. The technique is based upon free-field measurements as corrected by the relative elevation of the track and the attenuation by structures in the sound path. Although any train speed and desired noise level can be accommodated by the prediction method, a case study is presented which examines the location of the 65-dBA isobar created by 40-mph (66-km/hr) trains passing through an urban area. The noise analysis formed a crucial part of the environmental statement exploring the impact of relocating train tracks from the heart of the city to a corridor along the river. A sophisticated data acquisition and analysis procedure is presented. Ambient background noise levels throughout the city were determined and compared against the current 65-dBA train contours. The freight train noise prediction method permitted the probable 65-dBA isobar resulting from the relocated tracks to be estimated.