Watersheds
Surface Water
• Definition: fresh water on the Earth’s land surface
– Is found in lakes, rivers, streams, and wetlands
• Types of surface waters are:
– River systems
• Mississippi, Amazon, Nile
– Watersheds
• Definition: area of land that is drained by a river
– Example: Mississippi Watershed
A Watershed
• Definition - The total
land that contributes
water (or drains into)
a particular waterway.
• Can also be called a
"Drainage Basin"
A Watershed
http://www.ugwawv.org/images/watershed_large.jpg
All of the
water within
the area drains
into the central
waterway and
to a specific
point along
that waterway.
Watershed or Drainage Basin
• The drain board under a kitchen sink
drying rack is like a watershed.
The "Dry Dish"
Watershed
Go with the Flow
• Water always follows the path of least
resistance....
DOWNHILL!
• Water that flows through a Watershed:
-Streams, Creeks, and Rivers
-Surface runoff (water across the land surface)
-Groundwater (under the surface)
All three interact with each other!
Flow: Streams and Rivers
Flow: Surface Runoff
• Surface Runoff can also be called Overland
Flow
http://t2.gstatic.com/images?q=tbn:ANd9GcTNLL3TB1lwMw7XT0cgjqD2
Tdk69LGaoMMKXvWPCWAB_rtk4OXaaz63sOa-
http://www.gardening.cornell.edu/news/images/lawn.jpg
http://1.bp.blogspot.com/_3k4d15i2OAA/TMcWeF0DXzI/AAAAAA
AAFtU/tAwW5Z1C9JI/s400/parking+lot+runoff+2.JPG
Includes over forested land, grassland, and parking lots
Flow: Groundwater
Under the surface Groundwater is on the
move
http://savethewater.org/wp-content/uploads/2012/07/Maryland-groundwater-diagram-pubs-usgs-gov.jpg
Fuel for the Flow: The Water Cycle
The Water
Cycle
provides the
water to
create
these three
types of
flow.
Watersheds Land Area
TOPOGRAPHY
(Shape of the lands surface)
Determines
what area
will make up
a watershed
http://www.nrcan.gc.ca/sites/www.nrcan.gc.ca.earth-sciences/files/jpg/h2o/bowen/images/watershed_e.jpg
Watershed Topography
Low points in a watershed:
Stream or river itself, the very bottom
http://www.americanwhitewater.org/photos/archive/medium/10211.jpg
Watershed Topography
Highpoints in a watershed:
Hills, Mountains, or ridges surrounding the
waterway.
http://mysticsail.com/wpcontent/uploads/2009/03/rotui-web.jpg
http://farm4.static.flickr.com/3487/4060038327_5088e10425.jpg
http://www.birdsasart.com/rootjpegs/Mount%20McKinley.jpg
Watershed Boundary
The watershed boundary is created by the
high points of land surrounding a
waterway
Watershed
Boundary
http://www.thinkbluemaine.org/images/kids/watershed%20-%20edit.jpg
http://www.kidsgeo.com/images/watershed.jpg
Watershed Boundary
Any water within
the boundary
of your
watershed or
precipitation
that falls
within the
boundary will
flow into your
waterway
http://www.pedrocreek.org/images/watershed_drawing.gif
Watershed Boundary
Any water OUTSIDE
the boundary of
your watershed
or precipitation
that falls
OUTSIDE the
boundary will
flow into a
different
waterway is part
of a different
watershed.
http://water.me.vccs.edu/courses/CIV246/changes/watershe.gif
Watershed Boundary
• The watershed boundary is the dividing
line between two watersheds
• Watershed boundaries are sometimes
called Watershed Divides
http://www.fs.usda.gov/Internet/FSE_MEDIA/stelprdb5361417.jpg
Many Watersheds
Does your favorite
stream have a
watershed?
http://www.fws.gov/chesapeakebay/Newsletter/Summer05/Streams/Flowing%20stream.
gif
All waterways, large or small, have a watershed.
Waterways always have land surrounding them that
drain into them.
Small creek=Small watershed Large Creek=Larger Watershed
Build up a Waterway
waterways flow into one another.
small creeks flow into
Large creeks
which flow into
LARGER
creeks
or a river!
http://www.fgmorph.com/images/04/04_08_01.gi
f
Build up a Watershed
Watersheds interact with one another too.
Small watersheds make up
Larger Watersheds
which
make up
http://epa.gov/gmpo/images/lower_missis
sippi_map.jpg
Even LARGER Watersheds
Scale
Watersheds work on
different scales
Allegheny
River
French
Creek
Suga
r
Cree
k
• small creeks have small
watersheds
• large creeks include the
•
watersheds of many small
creeks
rivers include the combined
watersheds of many large
creeks
No Watersheds Somewhere?
Is there any place on land that is not part
of a watershed?
No, Everywhere you stand on the Earth's
land surface drains somewhere, so it is
part of a watershed, whether big or small.
What is YOUR Watershed?
• Small watershed?
• Big watershed?
• Where does your
water flow to?
• Which of the
major watersheds
in Costa Rica are
you in?
Watershed Impacts
• Our Water Cycle
The Fuel that Runs the Watershed
http://web.bryant.edu/~langlois/ecology/hydrocyc.gif
Watershed Impacts (Rural)
Land and waterway interaction
http://media.sanluisobispo.com/smedia/2012/03/14/18/30/1dSwQC.MiSt.76.jpg
What we do on our land
affects our waterways
http://water.epa.gov/scitech/datait/tools/warsss/images/fig32.jpg
Watershed Impacts (Urban)
Land and waterway interaction
http://upload.wikimedia.org/wikipedia/commons/8/8d/Allegheny_River_Pittsburgh.JPG
What we do on our
land affects our
waterways
http://www.twpusc.org/comdev/stormwater/photos/stream21_lg.jp
g
Watershed Impacts (Residential)
Land and waterway interaction
http://farm1.static.flickr.com/11/12774549_1f8ae21d9a.jpg
What we do on our
land affects our
waterways
http://www.seagrant.umn.edu/newsletter/2002/06/images/lake_fertilizer.jpg
Watershed Impacts
• We influence our waterway and
watershed
Direct Impact on Waterway
•
Dumping into creek, littering into creek
Impact on Land Surrounding Waterway (Watershed)
•
•
•
Poor land use decisions
Disturbing the land without minimal impact
Contributing to pollution on the land
Watershed Impacts Downstream
• We are connected to others
downstream
• Our waterway flows into other
waterways
• Our watershed drains into other
watersheds
• Our mess/pollution travels
downstream
Watershed Impacts
What will YOU do to protect your watershed?