What are "Waters of the United States," as defined in the Clean Water Act?
Defining "waters of the United States" is essential because those bodies of water that are considered to fall under this definition are governed by a federal act called the Clean Water Act (CWA). The definition of "waters of the United States" has been clarified by the US Supreme Court so that individuals can understand exactly which bodies or types of water the CWA applies to.
The Clean Water Act of 1972 was drafted as a means of protecting the country’s natural wetlands and resources by enforcing national pollution laws. This federal act was designed to protect all inland and territorial waters of the United States from runoff pollution and from pollution by dredging or dumping into natural lakes and rivers within any of the 50 states. Due to a variety of different lawsuits involving the CWA, the United States Supreme Court in 2006 defined the terms as used in the act, which were described as “Waters of the United States”.
The definition given by the Supreme Court that year gave meaning to the term by pointing out that the act was meant to protect any continuously flowing water bodies (rivers, streams, springs, and creeks), any inland lakes, reservoirs, or ponds, or any other permanent or relatively permanent bodies of water which constitute geographic features within the United States. This act is also applied to the boundary waters of the United States, which means that any ocean water within 12 miles of any part of United States coastline is considered “Waters of the United States”.
Today, almost all bodies of water in the US - from streams to rivers to wetlands - are considered "waters of the United States." The water doesn't need to be navigable. If you are concerned about whether a given body of water is one of the "waters of the United States" and thus subject to federal Clean Water Act regulations, it is in your best interest to consult with a lawyer. Your lawyer can help make sure any actions you take are in full compliance with the law.