The Connecticut River Watershed Partnership Act directs the Secretary of the Interior to establish a non-regulatory program to coordinate restoration and protection efforts across the Connecticut River Watershed, which spans Connecticut, Maine, Massachusetts, New Hampshire, and Vermont. The bill creates a grant program to provide competitive matching grants to states, tribal governments, local governments, nonprofits, and colleges to fund restoration projects, with federal funding covering up to 75 percent of project costs, or up to 90 percent for projects serving environmental justice communities. The program aims to accomplish multiple goals including improving water quality, restoring fish and wildlife habitats, building climate resilience, enhancing public access and recreation, protecting farmland, and promoting traditional tribal ecological practices. The bill authorizes unspecified funding for fiscal years 2026 through 2030, with at least 75 percent of appropriated funds dedicated to grants and technical assistance, and requires annual congressional reports on program implementation. The Secretary must establish both the partnership program and grant program within 180 days of the bill's enactment.