The Westchester County Department of Public Works undertook this traffic signal re-timing study and emissions analysis on behalf of the municipalities in the county to identify routine maintenance improvements which would provide better traffic operations, reduce vehicle emissions and improve air quality.

The study was also performed to identify traffic signal upgrades that could further improve traffic emissions and air quality and to provide the quantitative data for the respective municipalities to apply for federal or state funding, such as CMAQ, targeted for air quality improvements and congestion mitigation.