‘Water quality’ means different things to different people. In the legal arena of the federal Clean Water Act, ‘water quality’ refers to the suitability of water for a specific purpose (called a ‘designated use’) based on a set of physical, chemical, and biological factors. Common designated uses of water include drinking, agriculture, industry, swimming, and boating. Water quality standards developed by each state, and approved by the EPA, identify designated uses for each water around the state. The standards also outline the physical, chemical, and biological characteristics that must be present for that water to meet its designated use.
People also use the term ‘water quality’ as a catch-all for the overall cleanliness and ‘health’ of water. This makes it easier to talk about big picture goals for water in general, but if we want to reach those goals, it is important to understand how the Clean Water Act and the Water Quality Standards work.
Vermont’s Water Quality Standards are reviewed and revised every 3 years. The current set of standards and the 2022 proposed revisions are available through the links below. Further information can also be found online here. The Vermont Department of Environmental Conservation (VT DEC) is responsible for maintaining and enforcing the Water Quality Standards. They also monitor and evaluate the quality of water across the state.