There are two basic kinds of floods, flash flood
Flood predictions require several types of data:
The USGS usually corrects any equipment or station problems within a few days of their occurrence. Occasionally, replacement parts or equipment might not be readily available, or a station might be inaccessible due to weather conditions.
1. 1797: A magnitude 8.4 earthquake near the central part of the western Sumatra generated a tsunami that flooded Padang. More than 300 fatalities.
At some USGS stream-gage installations, NOAA’s National Weather Service (NWS) maintains a separate stage sensor that is serviced by NWS technicians.
Stream stage is an important concept when analyzing how much water is moving in a stream at any given moment. Stage is the water level above some arbitrary point in the river and is commonly measured in feet.