Greenhouse Gas (GHG) Program

GHG Transportation Planning Standard

On December 16, 2021, the Transportation Commission voted to approve a groundbreaking new rule, the GHG Transportation Planning Standardwhich will reduce pollution and greenhouse gas (GHG) emissions from the transportation sector, improve air quality and reduce smog, and provide more travel options for Coloradans.

The GHG Transportation Planning Standard is one of several transportation strategies identified in the state’s Greenhouse Gas (GHG) Pollution Reduction Roadmap and is a key requirement established in the 2021 state transportation funding bill (SB260). Colorado's GHG Pollution Reduction Roadmap was updated in 2024, "Roadmap 2.0".

The Standard focuses on transportation planning — the process for how CDOT and the state’s largest metropolitan regions select future transportation projects. Long before a transportation project is built, it is first identified in plans developed with local public input. These plans often include a decade or more of projects and thus represent a short- and medium-term vision for coming changes. 

Under the Standard, CDOT and the state’s five Metropolitan Planning Organizations (MPOs) are required to achieve individually set GHG reduction levels at four different time periods - 2025, 2030, 2040, and 2050. To determine compliance with the reduction levels, agencies must model their existing transportation networks and all future regionally significant capacity projects in their transportation planning documents (CDOT’s 10-Year Plan and Four-Year Prioritized Plan in Non-MPO area, and the MPO’s fiscally constrained RTPs) using travel demand models, with a subsequent analysis through EPA’s Motor Vehicle Emission Simulator (MOVES). Overall, the standard encourages CDOT and the MPOs to develop long range transportation plans that support travel choices that reduce GHG emissions.

On September 15, 2022, the Transportation Commission voted to approve CDOT’s newly updated 10 Year Plan and associated GHG Transportation Report, which shows compliance with the GHG reduction levels in the rule and is required by October 1, 2022 by the GHG Planning Rule and SB260. For a copy of the GHG Transportation Report, please email Libba Rollins ([email protected]).

The Transportation Commission also voted via resolution to accept DRCOG and NFRMPO’s GHG Transportation Report which also shows compliance with the GHG reduction levels in the rule. These three agencies are in compliance with the GHG Planning Standard. The planning documents of PPACG, PACOG, and GVMPO will be subject to the rule following October 1, 2022.

About the Rule

GHG Mitigation Measure Policy Directive

On May 19, 2022, the Transportation Commission voted to adopt Policy Directive 1610 on GHG Mitigation Measures. Email Libba Rollins ([email protected]) for a copy of Policy Directive 1610. The Policy Directive fulfills the requirements of the GHG Planning Standard, adopted by the Commission in December 2021, to establish an ongoing administrative process and guidelines for selecting, measuring, confirming, verifying, and reporting on GHG Mitigation Measures.  

GHG Mitigation Measures are an important, but voluntary, component of the GHG Transportation Planning Standard. Policy Directive 1610 provides an additional compliance mechanism for CDOT and the state’s five MPOs to meet the GHG Reduction Levels found in the Planning Standard.  

As per the requirements of the GHG Transportation Planning Standard, agencies will model the travel impacts of their transportation plans using travel demand models, with a subsequent GHG analysis of these plans through EPA’s Motor Vehicle Emission Simulator (MOVES). If agencies do not meet their individual Reduction Levels as required by the Planning Standard, they can  change the mix of projects in their transportation plans and/or use GHG Mitigation Measures. GHG Mitigation Measures are projects and strategies whose GHG and travel benefits cannot be accurately or easily captured and quantified in travel demand models.   

Appendix A in Policy Directive 1610 includes a list of GHG Mitigation Measures that have been reviewed, vetted, and scored by CDOT subject matter experts and formally approved by the Transportation Commission. These approved GHG Mitigation Measures are “scored”, which reflects the ability of a project to reduce GHG emissions relative to a certain metric, while providing a way to distinguish and value the location and context. One point is equivalent to one metric ton of avoided GHGs. If you would like to see the calculation methodologies for any of the GHG Mitigation Measures included in the Appendix, please email Libba Rollins  ([email protected]). Any individual or organization may nominate new GHG Mitigation Measures for review and potential approval by filling out a form on CDOT’s website here.