Setting reference marks

(Credit: Rena Kalmon, U.S. Geological Survey, New England Water Science Center. Public domain.)
Detailed Description
Surface Water Modeling for FEMA Flood Insurance Rate Maps.
USGS employees use a GPS to set reference marks next to a damn near St. Johnsbury, VT.
Details
Image Dimensions: 1920 x 1080
Date Taken:
Location Taken: VT, US