USGS WATER DATA
HOW TO INTERPRET THE DATA
Flood Stage/Gage Height: The most useful information on this graph is to know if the river level is rising or falling. The gauge height can also be useful if you’ve previously paddled the same stretch of water and want to compare where it is now to where it was then. Beware that the gauge height reported isn’t indicative of how many feet of water there is in the river everywhere – it’s only telling you how many feet of water there is in that specific location – which may be shallow or may be a deep pool or somewhere in between.
Discharge State:This gauge tells you how much water there is and how fast it is flowing. How high a particular river is at is dependent upon the size of the river canal. A good rule of thumb is if the gauge is below 100 cfs, it will be a tough paddle. The yellow triangles indicate what the mean flow has been over a number of years and should tell you if the river is running average, low or high.
Percentile: This is the real-time percentage of distribution compared to the same day of the year historically. If the river you’re planning to paddle has this metric, it means there have been at least 30 years of data collected there.
Precipitation: This tells you the amount of precipitation at a specific location. Generally, if it hasn’t rained you can expect that the river levels will drop and if has rained the river levels should rise.
USGS Water Alert Subscription
The U.S. Geological Survey WaterAlert service sends e-mail or text (SMS) messages when certain parameters, as measured by a USGS real-time data-collection station, exceed user-definable thresholds. The development and maintenance of the WaterAlert system is supported by the USGS and its partners, including numerous federal, state, and local agencies.
Real-time data from USGS gages are transmitted via satellite or other telemetry to USGS offices at various intervals; in most cases, 1 to 4 times per hour. Emergency transmissions, such as during floods, may be more frequent. Notifications will be based on the data received at these site-dependent intervals.