6/17/08
When we were fishing the Great Smoky Mountains National Park last week, my
grandson ask me “where does the water come from”. I thought that was a good
question and maybe one that a lot of other folks may not have thought about.
A freestone stream is born at the top of mountains as drops of rainwater and
melting snowflakes. As gravity forces these droplets to seep through the
crevices of rocks, soil and organic matter, they combine into small trickles of
water. These trickles eventually collide and become larger and larger. They form
tiny streams that you can step across. The tiny streams eventually join other tiny
steams to form larger ones. These tiny streams are made larger along the way
by many other trickles of water and eventually become streams that are large
enough to be named and shown on maps. These streams are usually the
headwaters of what will become a large freestone stream or river.
Generally, water in the headwater streams is fast moving pocket water. Most
headwaters fall through steep gradients and rapidly flow downhill. As the stream
reaches the lower elevations of the foothills the gradients become less and less
and the flow of the water decreases accordingly. As more and more water
collects the streams become wider. The water in the larger streams slows as it
moves through the valley.
As the stream reaches the lower elevations of the valley and the flows decrease,
the temperature increases. Eventually the water will become too warm to support
trout and other warm water species of fish such as smallmouth bass will become
more prevalent. The slower moving water will not hold as much dissolved oxygen
as the faster moving headwaters. This also becomes an important factor in the
stream’s ability to support trout.
Coming Up Next:Freestone Streams – Part 2
Copyright 2008 James Marsh