An official website of the United States government. Here's how you knowHere'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.
Latest Earthquake | Chat Share
Our mission is to collect and disseminate reliable scientific information on issues affecting rivers, lakes, estuaries, groundwater, and water resources. Find data resources associated with our work here.