Rain and snow may fall on a forest canopy or on a roof,
but the water always flows somewhere. On its way downhill,
water passes over and through many parts of the land.
It may soak into the soil and flow underground, or follow
a paved street to a storm drain. It can take minutes to years
to flow through part of the watershed. Along the way, water
picks up and moves soil, litter, pollutants, and other materials
from natural and man-made sources.
Within a water shed all things are linked by water. Watersheds can cross city, state, and international borders. When people make changes to their landscape, they often alter how water moves though their watershed. These changes can affect the quality of water and quality of life for communities, both human and wild, living downstream.