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.
Acoustic echosounders were installed on the selected bridges to measure streambed elevations adjacent to supporting piers in real-time and deliver the data through available USGS web-based services.
Public Domain.
