Project Description
LEA was retained by the City of Toronto to prepare a Noise Impact Study to assess the existing and future noise impacts from road traffic on Highway 2A. This study evaluated its potential impact on sensitive receptors in the study areas north and south of Highway 2A.
The study aimed to assess the levels of vehicular traffic noise that residential areas of concern were exposed to, focusing on specific receiver locations of interest.
The aforementioned receiver locations of interest were the noise-sensitive receptors in the north study area of Highway 2A, including the residences along Franklin Avenue, Tanis Crescent, Meadowvale Road, Stagecoach Circle, Culloden Court, Kingston Road, Valmount Avenue, and Centennial Road, which have a direct sightline to Highway 2A. The noise-sensitive receptors in the south study area include the residences along Newmains Court, Evenwood Avenue, Cedarview Drive, Satchell Boulevard, Meadowvale Road, and Lawson Road, which also have a direct sightline to Highway 2A. The northern and southern study areas are bounded by Centennial Road to the east and the Highland Creek Overpass to the west. The surrounding land is mixed-use, which includes mostly residential zones and some commercial and institutional zones.
LEA was to provide an evaluation of the potential acoustic benefits of constructing a road traffic noise wall and to recommend appropriate mitigation measures and benchmark costs, if necessary. During the evaluation process of noise impacts, all properties located on the first row within the study area were assessed on their most exposed side. This was expected to be completed within six (6) months.
Utilizing road data from the City, noise level calculations were performed in accordance with ORNAMENT and the methodology outlined in the MTO Guide. Road traffic sound levels were modelled using noise propagation modelling software CadnaA, version 2020, based on the ISO 9613-2 standard: “Acoustics-Attenuation of sound during propagation outdoors – Part 2: General method of calculation” (1996). Within CadnaA, road noise emissions were modelled using the Traffic Noise Model (TNM) Version 2.5 algorithm, the current STAMINA methodology approved for use in the MTO guidance document. The TNM algorithm is a widely accepted and recognized method for noise modelling in transportation engineering. Its use is particularly relevant in the analysis of traffic noise impacts and mitigation measures associated with roadway design and construction projects.
Long-term sound level measurements were collected across the Study Area at locations with direct line-of-sight exposure to noise from road traffic on Highway 2A to establish a background noise level. As mentioned above, for modelling purposes, traffic data counts related to Highway 2A were obtained from the City. This data was grown to the year 2041 with a yearly growth rate of 1.13% compounded over 17 years as recommended by the City. Based on these field measurements and analysis, most of the existing residential receptors were exposed to sound levels above the 60 dBA Leq-24hr noise limit.