This bill aims to cut climate and air pollution from large ships that carry cargo or passengers to and from U.S. ports. It sets step-by-step limits on how “carbon intense” ship fuel can be, based on a 2027 baseline, and requires zero-emission operations while ships are at the dock or anchorage by 2035, unless that is not technologically or economically possible, in which case the strongest feasible cuts must be made .

Key points

• Who is covered: Commercial voyages to, from, or between U.S. ports, on vessels 400 gross tons or larger. Ships with 30 days or fewer of these voyages in a year are exempt for that year .
• Fuel standards: Required cuts from the 2027 average fuel carbon intensity are at least 30% in 2030–34, 58% in 2034–39, 83% in 2040–44, 92% in 2045–49, and 100% from 2050 onward. EPA must finalize the first set by Jan 1, 2029, and later ones two years before they start.
• In-port emissions: EPA must set rules so ships at berth or anchorage in U.S. waters eliminate greenhouse gases and major air pollutants by 2035, or achieve the maximum feasible reductions if full elimination isn’t feasible, considering health and environmental impacts.
• Reporting and transparency: Each year, ship owners must report fuel carbon intensity, fuel used per voyage, and total greenhouse gas emissions. EPA will publish a public report, and DOT will repost it.
• Flexibility: EPA may align methods with European Union and International Maritime Organization systems, adopt IMO standards if they are as strong or stronger, let companies average performance across commonly owned ships, and allow banking of overcompliance for future years .

What this could mean for communities: cleaner air around ports as ships cut pollution at the dock, clearer public data on ship emissions, and a long-term push for cleaner marine fuels and equipment .