Virginia Watersheds

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Virginia Watersheds

• Mathematics Science Center

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What is a Watershed?

• Its the land that water flows across or under
  on its way to a stream, river or lake.

A watershed with its small streams and larger
river can be compared to a leaf with its
sub-veins and main vein.
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Watershed Movie
Courtesy of Michigan Environmental Education
Curriculum
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We all live in a Watershed
Courtesy of DCRs Soil Water Conservation
Programs

• In the mountains or where the land is flat.
• In cities, forests and on farms.
• Even plants and animals live in a watershed.

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Watersheds Vary In Size
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Hydrologic Units
The United States is divided and sub-divided into
successively smaller hydrologic Units.

• The Four Levels
• Region
• Sub-Region
• Account Unit
• Cataloging Unit

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What is a Divide?

• A divide is the boundary that separates one
  watershed from another.

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What is a Tributary?
A tributary is a stream or river that contributes
its water to another stream, river or body of
water.
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Two Kinds of Water Pollution

• Point Source Pollution
• Nonpoint Source Pollution

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Point Source Pollution

• Its usually easy to figure out where point
  source pollution comes from. If you see a pipe
  emptying into the water, thats a point source.
  You can point to where its coming from.

Courtesy The Scottish Agricultural College
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Nonpoint Source Pollution
Courtesywww.deq.gov

• Nonpoint source pollution comes from places you
  cant easily identify
• Rain washes loose soil off construction sites
• Rain washes oil and litter off parking lots
• Extra fertilizer on lawns wash into our water
• Acid rain exhaust from cars

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Why Do We Study Watersheds?

• Every place in Virginia belongs to a watershed.
• The quality of water in each stream and river
  depends in large part on the land use in the
  watershed.
• Land used for residential, agricultural, or
  commercial areas can either hurt or support water
  quality.
• Knowing where your water comes from is
  important, especially if any problems occur
  upstream.