EPA Releases New Definition on Waters of the United States
The revised definition identifies four clear categories of waters that are federally regulated. These included territorial seas and traditional navigable waters; perennial and intermittent tributaries; certain lakes, ponds and impoundments; and wetlands adjacent to jurisdictional waters. Note that ephemeral tributaries (i.e., those that flow only in immediate response to rainfall events) waterbodies that are adjacent to them are excluded from regulation under the revised definition.
It also details other exclusions from federal control such as water bodies that are only created due to direct rainfall, groundwater, farm and stock watering ponds and waste treatment systems.
Read the full EPA press release regarding the proposed definition here.