How Watersheds Work 157
How watersheds protect water and soil
Most of the water in a watershed is not in the rivers and lakes, but in the soil
itself. A healthy watershed has a supply of clean water and rich soil. Trees and
plants, especially grasses, in the higher parts of the watershed and along the
banks of rivers and streams, improve the quality and quantity of groundwater.
By protecting and conserving water, plants, and soil, we protect the watershed.
Plants and trees slow
the rainwater, help it
spread and sink into the
ground, and prevent it
from carrying off too
much soil.
Flowing rivers and streams
support people, fish, and animals.
When water enters rivers slowly
through the ground, there is more
water in the river between rainfalls
and less flooding during storms.
Wetlands, often at the
bottom of a watershed,
filter and clean water as it
moves along. Wetlands can
even filter out some toxic
contamination.
A Community Guide to Environmental Health 2012