I'm doing a report on the effects of flooding on the environment. Can you help me? What can people do to help ease flooding? I live in an area where flooding hardly occurs; What could I do to help people that live in those areas?
You asked about the effects of flooding on the environment.
This is a pretty broad question, but I'll try to provide some
answers to what I think you are asking about.
First, floods are part of the natural cycle of things. The
benefits of natural floods almost certainly outweigh the
negative aspects. The problems start when flooding occurs
in areas of large-scale human development of the landscape.
In areas largely inhabited by people, there are
both positive and negative environmental effects of flooding.
Floods can distribute large amounts of water and suspended river
sediment over vast areas. In many areas, this sediment helps
replenish valuable topsoil components to agricultural lands
and can keep the elevation of a land mass above sea level. An
example of the latter case is the Mississippi delta. Before the
Mississippi and associated rivers were controlled in levees in
southern Louisiana, the rivers would frequently spill their banks.
This processes made the lands of the Mississippi delta. This
area is slowly subsiding with time and without the continued
replenishment of sediment from river floods, much of it has dropped
to elevations below natural sea level. Thus, one could say that
not allowing floods is negative for this area. Our society has
chosen instead to create a vast and complex system to keep
Mississippi waters from reaching these lands. The lands remain dry
but each year they subside more, making it ultimately more and
more difficult to keep that way.
On the negative side, floods disrupt normal drainage systems in
cities and typically overwhelm sewer systems. Thus, raw or
partially raw sewage spills are common in flooded area. Additionally,
if the flood is severe enough, destruction of buildings that
can contain a large array of toxic materials (paints, pesticides,
gasoline, etc..) can cause the release of these materials into
the local environment, which is not good. I'm sure you
could imagine other "negatives" similar to those I've just described.
Floods disrupt many people's lives each year and personal
tragedies due to flooding occur frequently. A wise society, in
my opinion, would reap the benefits of flooding and avoid many
of the negatives if they would choose to build cities in ways that
can accomodate flooding without trying to avoid it. Attempting
to go against nature is almost certainly a loosing prospect in the end.
Flood prevention is really something left up to cities and towns.
If where you live isn't flood prone, maybe there is some
other natural hazard that does affect your area that you could
learn about and help with instead. As individuals, if we all keep
the minimum amount of toxic substances (paints, solvents, automotive
fluids, etc..) around our homes, there will be less of these substances
to "spill" when any sort of unfortunate natural dissaster befalls
the communities in which we live.
Ken Rubin, Assistant Professor
Department of Geology and Geophysics
University of Hawaii, Honolulu HI 96822
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