River gauges measure water level and water flow. This information can be used to determine the safety and comfort level of paddling at a given time.

When looking at the USGS webpage, the area where you need to obtain your information for flow rate is located under "Daily Discharge, Cubic Feet Per Second" and read the "Most Instantaneous Value" to get your cubic feet per second.  The graph below the "Daily Discharge" shows you the depth of where the water was read - not the depth of the river itself.