The bill, designated as Substitute Senate Bill No. 1083 with File No. 251, proposes the establishment of a transportation carbon budget for the state of Connecticut. This budget, effective from October 1, 2023, would require the Commissioner of Transportation, in consultation with the Commissioner of Energy and Environmental Protection, to set a maximum limit on greenhouse gas emissions from the transportation sector by July 1, 2030, and to update this annually. The bill mandates the consideration of long-term emission reduction targets as specified in section 22a-200a of the general statutes. The Commissioner of Transportation is also tasked with adopting regulations to ensure that transportation projects by the Department of Transportation, metropolitan planning organizations, and municipalities do not exceed the established greenhouse gas emissions limit. These regulations must include a definition of "transportation project," a methodology for calculating expected emissions from future projects, ways to offset increased emissions, and a description of greenhouse gas mitigation transportation projects.

The bill further requires the implementation of a public outreach plan to engage stakeholders in the development of the transportation carbon budget and the associated regulations. The Commissioner of Transportation must submit annual reports to the General Assembly's joint standing committees on transportation and the environment from January 1, 2025, until January 1, 2030, detailing the progress of the carbon budget and regulations, stakeholder collaboration, and public outreach efforts. Additionally, starting July 1, 2030, an annual submission of the transportation carbon budget and any legislative recommendations to the same committees is required. The bill's fiscal note indicates that while there are no expected costs during the biennium, there will likely be increased costs in the out years, potentially requiring additional full-time positions or consultant services at the Department of Transportation.