Available Tools
The Federal Highway Administration (FHWA) Office of Natural Environment developed a series of tools to provide technical support and resources for the implementation of the Congestion Mitigation and Air Quality Improvement (CMAQ) Program.
CMAQ project justification as well as annual reporting require the development of reliable air quality benefit estimates. Realizing that every potential project sponsor may not have the capacity for developing independent air quality benefit estimates, the FHWA has undertaken the initiative of developing a series of spreadsheet based tools to facilitate the calculation of representative air quality benefit data.
This CMAQ Emissions Calculator Toolkit (in Microsoft Excel format) is only offered as an additional resource to assist DOTs, MPOs and project sponsors in the project justification process. Agencies and individuals using a preferred methodology to generate air quality benefit information are welcome to continue their current practice. The tool kit will be released in modules by project type.
CMAQ Toolkit Video Series: FHWA is developing short 3–4-minute videos for each tool or set of related tools in the CMAQ Toolkit. See an overview video here and tool-specific videos on the cards below. New videos will be added as they are completed.
CMAQ Input Data Dictionary provides important details related to various inputs associated with emissions estimation processes for CMAQ project eligibility categories including inputs associated with the CMAQ Emissions Calculator Tools.
Use the cards below to explore the tools, documentation, and training.
Introduction
Traffic signal timings in adaptive traffic control systems (ATCS) can adjust to changing traffic environments based on traffic volume data collected by sensors deployed at individual intersections. This tool calculates emission reductions for projects that implement ATCS on a corridor with signalized intersections previously controlled by a time-of-day signal timing plan.
Original Release: March 2021
Latest Update: November 2022
Help Line
For help using this tool or to provide feedback, please email: CMAQ_Toolkit_Help@dot.gov
* For those wishing to view the corrected transcript, please click button at bottom of zoom screen and select AUDIO transcript
Introduction
Replacing convention fuels with alternative fuel types reduces transit emissions. This tool calculates emissions reductions from purchasing vehicles to replace a convention fuel fleet or developing new alternative fuel infrastructure with restricted or unrestricted access.
Original Release: May 2018
Latest Update: November 2022
Help Line
For help using this tool or to provide feedback, please email: CMAQ_Toolkit_Help@dot.gov
Introduction
The Shared Micromobility Module was added to the existing Bicycle and Pedestrian Improvements Tool to create the new Bicycle, Pedestrian, and Shared Micromobility Projects Tool. The Shared Micromobility Module evaluates emissions benefits from the implementation of a shared bicycle or scooter project. Emissions benefits are based on the number of personal vehicle trip miles that are replaced by trips using shared micromobility devices.
Original Release: August 2019
Latest Update: October 2023
Help Line
For help using this tool or to provide feedback, please email: CMAQ_Toolkit_Help@dot.gov
Introduction
Carpooling and vanpooling encourage participants to commute together and reduce vehicle activity. This tool calculates emission reductions from projects that start carpool and vanpool programs, increase ridership in existing programs, or purchase vehicles for vanpool programs.
Original Release: May 2018
Latest Update: September 2022
Help Line
For help using this tool or to provide feedback, please email: CMAQ_Toolkit_Help@dot.gov
Introduction
Reducing congestion and improving traffic flow along a roadway improves roadway performance and reduces emissions from passing vehicles. This tool calculates emission reductions from intersection improvements, traffic signal synchronization, and roundabout projects.
Original Release: July 2019
Latest Update: December 2022
Help Line
For help using this tool or to provide feedback, please email: CMAQ_Toolkit_Help@dot.gov
Introduction
Projects that replace or retrofit diesel nonroad engines can help reduce emissions associated with construction, rail yard, and port activity. This tool estimates emission reductions from the retrofit or repower/replacement of diesel construction and intermodal equipment.
Original Release: April 2022
Latest Update: N/A
Help Line
For help using this tool or to provide feedback, please email: CMAQ_Toolkit_Help@dot.gov
Introduction
Idle reduction technologies are devices that enable diesel engine operators to refrain from long-duration idling of the main propulsion engine (referred to as "extended idle") by using an alternative power source. This tool calculates emission reductions from the application of idle reduction methods to diesel long-haul truck operations.
Original Release: November 2018
Latest Update: November 2022
Help Line
For help using this tool or to provide feedback, please email: CMAQ_Toolkit_Help@dot.gov
Introduction
Engine retrofit technologies and newer model year engines reduce vehicle emissions. This tool calculates emission reductions from retrofitting a heavy-duty diesel vehicle with a retrofit technology or repowering/replacing the heavy-duty vehicle with a more recent model year.
Original Release: May 2018
Latest Update: March 2022
Help Line
For help using this tool or to provide feedback, please email: CMAQ_Toolkit_Help@dot.gov
Introduction
Significant atmospheric dust arises from the mechanical disturbance of both paved and unpaved road surfaces by vehicle traffic. This tool calculates emission reductions from dust mitigation projects for paved roads, unpaved roads, or paving an unpaved road.
Original Release: February 2020
Latest Update: November 2022
Help Line
For help using this tool or to provide feedback, please email: CMAQ_Toolkit_Help@dot.gov
Introduction
Electronic open-road tolling (EORT) projects include conversion of traditional full-stop or rolling-stop toll plazas to free-flow facilities with overhead gantries. EORT gantries are mounted with vehicle-to-infrastructure (V2I) technologies—such as high-resolution cameras for license plate reading and high-speed sensors for transponder detection—which help smooth the drive cycle and reduce congestion in tolling areas
Original Release: November 2021
Latest Update: N/A
Help Line
For help using this tool or to provide feedback, please email: CMAQ_Toolkit_Help@dot.gov
* For those wishing to view the corrected transcript, please click button at bottom of zoom screen and select AUDIO transcript
Introduction
Replacing convention fuel vehicles with electric vehicles reduces emissions. This tool calculates emissions reductions from purchasing vehicles to replace a conventional fuel fleet or developing new EV charging infrastructure with restricted or unrestricted access.
Original Release: November 2022
Latest Update: N/A
Help Line
For help using this tool or to provide feedback, please email: CMAQ_Toolkit_Help@dot.gov
Introduction
Rail and marine freight transportation are more fuel efficient than freight moved via trucks. This tool calculates emission reductions for projects that shift freight activity from highways to more efficient and cleaner transportation modes.
Original Release: October 2023
Latest Update: N/A
Help Line
For help using this tool or to provide feedback, please email: CMAQ_Toolkit_Help@dot.gov
Introduction
Retrofit technologies and newer engine model years reduce emissions from locomotive and marine vessels. This tool calculates emission reductions from implementing engine retrofitting or engine repowering and replacement for locomotive and marine vessels.
Original Release: October 2020
Latest Update: N/A
Help Line
For help using this tool or to provide feedback, please email: CMAQ_Toolkit_Help@dot.gov
Introduction
Managed lane (ML) facilities, such as high-occupancy vehicle (HOV) and high-occupancy toll (HOT) lanes, on freeways produce emission benefits through smoothing driving behavior, improving traffic flow, and increasing average travel speeds. This tool calculates emission reductions from construction of a new ML facility on a freeway or conversion of an existing lane to a ML.
Original Release: January 2020
Latest Update: December 2022
Help Line
For help using this tool or to provide feedback, please email: CMAQ_Toolkit_Help@dot.gov
Introduction
Commuting constitutes a significant portion of total annual household vehicle miles traveled. By reducing the number of employees who commute to physical office buildings each day, telework programs can decrease the total number of vehicles miles traveled and reduce commuting-related emissions. This tool provides estimates of emission reductions for CMAQ-funded projects that encourage employees to switch to a hybrid or fully remote work schedule.
Original Release: January 2024
Latest Update: N/A
Help Line
For help using this tool or to provide feedback, please email: CMAQ_Toolkit_Help@dot.gov
Introduction
Emission reduction technologies and newer engines or alternative fuels reduce transit emissions. This tool is a modification of a previous version updated to include electric repowering of conventionally fueled transit buses. The tool can calculate emission reductions from retrofitting diesel transit buses with emission reduction technologies, replacing diesel and compressed natural gas (CNG) transit buses (or engines) with newer diesel, CNG, or alternative fuel vehicles, and replacing conventional buses with battery electric versions.
Original Release: May 2018
Latest Update: September 2022
Help Line
For help using this tool or to provide feedback, please email: CMAQ_Toolkit_Help@dot.gov
Introduction
Increasing transit bus service and expanding transit bus fleet sizes encourages decreased passenger vehicle activity. This tool calculates emission reductions from diverting use of passenger vehicles to transit buses.
Original Release: May 2018
Latest Update: September 2022
Help Line
For help using this tool or to provide feedback, please email: CMAQ_Toolkit_Help@dot.gov
Introduction
Travel advisory projects may involve signage or other messaging that alert drivers of upcoming roadway conditions. This tool currently accommodates two types of travel advisories: variable message signs (VMS) and variable speed limits (VSL). VMS typically provide warnings about temporary road events such as congestion, construction, or inclement weather, while VSL adjust the permitted speed to make travel conditions safer in response to roadway conditions. Travel advisories can contribute to reduced emissions by modifying driving behavior and smoothing the drive cycle, resulting in fewer speed variations.
Original Release: September 2022
Latest Update: September 2022
Help Line
For help using this tool or to provide feedback, please email: CMAQ_Toolkit_Help@dot.gov
* For those wishing to view the corrected transcript, please click button at bottom of zoom screen and select AUDIO transcript
