the biggest threats to waters quality are the modifications
or changes weve made to the landscapes that water moves through.
Explore More about the ways weve interfered with the natural
hydrologic cycle and the effects of those changes.
Cycle of Life
you notice it or not, water is constantly on the move all around
us. Its falling to the land in the form of .
Its moving across landscapes making its way to streams. Streams
are running to rivers and rivers are running to oceans. Water is
and transpirating and absorbing. Water is the ultimate recycled
element thanks to the hydrologic cycle, which constantly moves water
from the atmospheredown to the planets surface and then
back into the atmosphere.
a natural system, with no human modifications, water "percolates"
through many different elements (sand and dirt, rocky and grassy
areas) before reaching waterways like streams and rivers. Those
elements help filter out pollutants. Sometimes they act as holding
areas, creating standing water waiting to go through the system.
Humans have made shortworking around this natural flow, forcing
water more directly into waterways, and making the water more vulnerable
to the natural landscapes, like tiling and uprooting prairies, were
made for many different reasons. Some were made to support agriculture;
forests were cleared and lands were drained. Other modifications
supported development of cities and towns, resulting in more
surfaces and less
ones. Major changes, like shifting a rivers course or straightening
its flow, were made to support navigation. Whatever the reasons
for the modifications, they had the same outcomechanging the
way water moves through landscapes, affecting what water comes into
contact with and ultimately, waters quality.
Modification to Urban Settings
changes could be made by city planners to protect water quality?
very act of development has a huge impact on water quality.
Nonpoint Source Pollution
are the sources of pollution and their and effects?
Modifications to Agricultural Settings
America looks very different now than it did when the European settlers
first arrived. More
programs have been developed to encourage farmers to restore environmentally
Facts: An Overview of Wetlands
preservation of existing wetlands and the restoration of wetlands,
which are both needed, is going to require a partnership between
farmers and environmentalists. And it will need to be done on private
land if it is to be effective." More
to Market Online Links
Interest Still Divided Over Water Use." This Market to
Market feature looks at the controversy of water rights taking place
in the the western part of the country.
Issues Trouble Rural America." This Market to Market feature
looks at water interests of farming and rural areas. Read about
flooding, drought, hydrologic modification, and more.