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.
Total dissolved solids (TDS) in surface waters affect water quality and useability and are of particular concern in the Colorado River Basin. Estimates of current and past TDS concentration and...
data.gov
An official website of the GSA's Technology Transformation Services