The main purpose of the Great Lakes Restoration Initiative Act of 2025 is to continue funding and support for the restoration and protection of the Great Lakes. This initiative aims to address environmental issues affecting the lakes, such as pollution, habitat loss, and invasive species, ensuring the health of this vital ecosystem. Key provisions of the Act include the reauthorization of funding for the Great Lakes Restoration Initiative. Specifically, it allocates $500 million each year from 2027 to 2031 to support various restoration projects.