Modification to Urban Settings
What changes could be made by city planners to protect water quality?
What would encourage developers to leave more natural areas? What
would be the economic impact?
What do you
see when you look at the landscape where you live? If you live in
a town or city, then houses, pavement and parking lots have most
likely replaced forests and fields, changing the view and the areas
hydrologythe way that water moves across the land.
While the act
of developing an urban area can have dramatic short-term effects
on water quality, the most enduring effect of urban hydrologic modification
is the creation of a huge imbalance between and
surfaces allow water to soak in and include lawns and parks. These
areas filter runoff, catching pollutants before they get into
surfaces resist water and include asphalt, concrete and even building
roofs. Water simply runs off these surfaces, moving toward the
lowest point, as water always moves. In its journey to the lowest
point, the water can pick up anything that is on the ground: trash,
sediment, gas, oil, chemicals, paints, the list goes on and on.
in an urban setting normally doesnt get sent to a
treatment plant. The runoff either moves into storm sewers which
carry it to streams or rivers, or it just keeps moving across surfaces,
eventually making its own way back to a stream or river. Either
way, it takes pollutants with it. Since it is impossible to track
pollutants back to their source in this scenario, urban runoff is
considered to be
What can be
done? Probably the most important step is to increase the amount
of water that soaks in to the soil. While it is important to keep
heavily traveled roads as hard surfaces, the other impervious surfaces
dont have to stay that way.
rain barrels to catch water from roof gutters.
- Use gravel,
pervious asphalt or grass paving on low use areas like driveways
and highway shoulders.
specially designed vegetated roofs instead of shingles for house