The committee also holds jurisdiction over water quality issues. Throughout her career in public service, protecting the Great Lakes has been one of Representative Miller's principal advocacies. She is a vocal proponent of policy designed to preserve and protect Michigan's most cherished natural resource. During the 113th Congress, as the only member of the committee from the state of Michigan, Miller tirelessly advocated for the Great Lakes during House and conference negotiations of the Water Resources Reform and Development Act (WRRDA) and secured the inclusion of her provision designating all ports and harbors on the Great Lakes as a single, comprehensive navigation system for budgeting purposes – the Great Lakes Navigation System – essentially allowing the Great Lakes ports and harbors to create a unified front when it comes to federal funding.