The U.S. Geological Survey has thousands of stream-gaging systems
installed nationwide. These systems measure the heights
of the water in streams. After
some computations, the amount of water flowing can be computed.
The technology is changing. The more modern systems detect
the heights of streams and transmit that information via satellites to
a USGS office. But in the past, wire recorders like this one
maintained our gage-height recording network.
Here's how these recorders work: This recorder is kept in a box
(made of metal to resist
bullets!) on top of a large metal pipe going down into the water. The round wheel in
front has a metal wire wrapped around it holding a float at one
end. As the water in the stream moves up and down, the water in the
stilling well moves, too. The float on the wire goes up and down
with the water. As the wire moves, it moves the ink pen, which
records the stream height on rolling paper, operated by a battery.
When technicians visit the site, they remove the paper roll and take
it back at to the office where they will analyze it.
With all these moving parts, you can see the opportunity for trouble. The newer automated instruments are more reliable and more efficient.
Measuring water
Human's influence
Water use
Water Science home page
U.S. Department of the Interior | U.S. Geological Survey
URL: http://ga.water.usgs.gov/edu/wirerecorder.html
Page Contact Information: Howard Perlman
Page Last Modified: Wednesday, 13-May-2009 16:23:00 EDT
