An official website of the United States government
Here’s how you know
Official websites use .gov
A .gov website belongs to an official government organization in the
United States.
Secure .gov websites use HTTPS
A lock (
) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.
Google Analytics Dashboard for Water quality of the Potomac River at Chain Bridge at Washington, D.C.; hydrologic-data report, 1978 water year
Water quality of the Potomac River at Chain Bridge at Washington, D.C.; hydrologic-data report, 1978 water year