The National Assessment Database summarizes electronic information submitted by the states to EPA.
This information should not be used to compare water quality conditions between states or to identify statewide or national trends because of
differences in state assessment methods and changes to EPA guidance. This represents the most recent electronically available state water quality
This website provides a summary of state-reported water quality information and allows the user to view assessments
of individual waterbodies. It presents data in a format designed for quick reference by water quality professionals and
those familiar with water quality reporting. EPA is working with the states to improve future electronic reporting.