Development and Application of Link-Level Vehicle Emission Inventory for the Metropolitan Area

摘要

Developing counties have been investing heavily on transportation projects. These projects bring good aspects that improve economic situation and mobility in the region. On the flipside transportation projects also may have an impact on environment with increase vehicle miles travelled and emissions. It is important to assess current on-road emissions to better plan control strategies that could help a region to attain the ambient air quality standards. On-road emission models can be used as planning tools in various settings. For example, metropolitan planning organizations (MPO), ranking projects for implementation, air agencies working on state implementation plan, state department of transportation working on National Environmental Policy Act (NEPA) analysis, etc. The two pieces of puzzle for estimating emissions are vehicle miles of travel (VMT) and emission factors. North Central Texas Council of Governments (NCTCOG) has automated the process by developing a module called EmiLink that is used on the back end of the regional travel demand model. Currently, using results from this tool, volume changes between a build and a no-build network are estimated for all roadway links for all analysis years. EmiLink has been successfully applied to numerous projects undergoing the NEPA process in the Dallas-Fort Worth (DFW) area, and has not only reduced the time required to complete a MSAT analysis, but also provides procedural and data assumption consistency. A case study was performed for the Loop-12 NEPA project in the DFW region which focused on pros and cons of the FHWA's current recommended procedure and other methods or parameters that can be utilized to identify transportation impacts in a project level MSAT analysis.