Whatzzzzup-stream?
Water goes with

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First-order streams are small.
Fourth-order streams are large.
Raise your hand if you live in a
watershed! Do you all have
your hands raised? Great!
Because we all live in a watershed.
No matter whether you live in the city
or the country, our land is sloping
toward the sea. This means that water
is always trying to flow downhill
to the sea. (Gravity at
work!) The next time ]
you are standing next
to a stream, think about
whatzzzzup-stream. Has
this water flowed past
another neighborhood
like yours? A forest? -i
A farm?
When water falls
as rain or snow, it
quickly runs together
into small streams. Even-
tually these small streams
flow into each other and form
rivers. Rivers, in turn, meet
to form larger rivers. From an
airplane you can easily see how
this stream network is organized.
It's kind of like a tree lying on its side
with many branches attached to a
main trunk.
Pick out any location in any
stream and all the land that contrib-
utes water up to that point is called
its drainage basin or watershed. The
watershed of a small stream—one
you can cross wearing only rubber
boots—might be only a couple of
acres in size. On the other hand, if
you need fishing waders to get across,
the stream is probably draining a
square mile or more of land. If scuba
gear is required, you know the stream
has a large drainage area. Knowing
where your water comes from is
important, especially if any problems
Streams are ordered according to their position in the watershed.
The smallest streams have a "1" and are called "first-order" streams.
Hydrologists (scientists who
study the movement of water) have
devised a system for classifying the
position of streams in a watershed.
The uppermost channels with no
tributaries are designated first-order
streams. A second-order stream is
formed when two first-order streams
meet. Third-order streams are created
when two second-order streams join,
and so on. A network is formed by
all the streams in the watershed,
and people can easily see how they
connect.
Like nesting dolls, small water-
sheds are part of larger watersheds,
which in turn are part of even larger
watersheds. To help keep everything
organized, the U.S. Geological Survey
developed a system to keep track of
all the different scales of watersheds.
There are four basic sizes of water-
sheds in their system. The largest are
known as the major river basins and
occur upstream. You probably would
not want to head out to your favor-
ite sw imming hole if that morning a
gasoline truck spilled some of its load
upstream.

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1 Let's
Go
— —j Surfing
Now!
Learn about your
watershed at...
http://cfpub1 .epa.gov/surf/
locate/index, cfm
EPA has developed a web site
that can help you identify the
watershed you live in and what
kind of activities occur in it. The
site can also help you join a local
watershed protection group or
volunteer monitoring association.
*	How many rivers and streams
are there in your watershed?
*	How much land does your
watershed drain?
*	Are there impaired waters in
your watershed?
*	What order stream is near your
home?
Let's Get
Our Boots
Muddy!
& &
Follow that Stream!
Find a stream near your house
and take a walk. (No trespassing
on private property!)
*	Walking upstream, do you see
any smaller streams flowing
into your stream?
*	What order is the stream?
*	Walking downstream, what
does your stream flow into?
*	After your walk, get on the internet
at http://cfpub 1. epa.gov/surf/
locate/index.cfm to find out
which watershed the stream is
in and how healthy its waters
are.
Major River
Basins
Catalog Units
The 18 major river basins in the 48 contiguous
states are subdivided into 2,111 catalog units.
include the Rio Grande River Basin
(13 on the Major River Basin Map)
in the Southwest and the Ohio River
Basin (5) in the Midwest.
The smallest watersheds defined
in the USGS watershed classifica-
tion system are called catalog units.
Generally, when people ask you about
your watershed, they are focusing on
the catalog unit-size watershed.
Most catalog units are named after
the major river that flows through
them.
Did you know?
Most Americans (218 million)
live within 10 miles of a
polluted lake, river, stream,
or coastal area.
w"
Career
Corner
A hydrologist studies the
dynamics of surface water.
A science teacher teaches young
people about science, including
organisms and environmental
processes.
A geographic information system
(GIS) analyst creates computer-
generated maps that can include
wetlands, waterways, and nearby land
uses that could affect them.
A soil conservationist provides
technical assistance regarding erosion
to fanners, ranchers, state and local
governments, and others concerned
about the conservation of soil, water,
and related natural resources.

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