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dam-l The Smithsonian's take on dams... an antidote to ICOLD
Dear listmembers:
I found this the day that Jacques Cousteau died. That was some time ago.
It is of course linked to the DRIIA page and has been since the day I
found it.
Given the "Educational" section I've sent along from ICOLD's
supposedly unbiased view that *ahem* <grim smile> perhaps this
might serve as an antidote, er, balance.
I know some fish species who would differ severely with ICOLD's supposedly
unbiased view. ;-> And some tree species come to thin of it. And some
native peoples.
For the record, my views and those of DRWG are based on at least 10
years of research - I used to believe that hydro was clean and perfect
energy. The information was so multidisciplinary and scattered it
was hard for an undergraduate not to have that kind of erroneous
view based on limited knowledge of the impacts literature.
I now have a balanced view. Given enough evidence it was inevitable.
I only wish I could say the same for ICOLD. But of course they have
paycheques resting on it whereas I do not.
Really it's all a matter of not OD'ing on any one form using common sense
and not just staying comfortable becasue one has a cushy job that pays a
lot rushing about being "un castor" as some inside Hydro-Quebec who don't
belive hydroelectric to be the saviour of humankind, call their pro-dam
collegues.
Castor, or beaver is a good image I think for the ICOLD crew.
In any event... the Ocean Planet site:
http://seawifs.gsfc.nasa.gov/OCEAN_PLANET/
is well worth a visit.
It was put together by a curator at the Smithsonian with the help
of NASA oceanographer Gene Carl Feldman. Lovely site either in
eyecandy Netscape or IE or Mosaic, as well as in lynx.
Bon appetit!
-Dianne
Forwarded message:
From dianne Mon Dec 6 16:57:42 1999
Date: Mon, 6 Dec 1999 16:57:41 -0500 (EST)
From: "D. Murray" <dianne@sandelman.ottawa.on.ca>
X-URL: http://seawifs.gsfc.nasa.gov/OCEAN_PLANET/HTML/peril_fresh_water.html
Subject: peril_fresh_water.html
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_________________________________________________________________
Pluses
There are over 75,000 dams in the United States, and more are planned.
Why? We divert river water to meet household needs, irrigate fields,
supply factories, control flooding, generate power, permit barge
traffic deep inland, and make lakes for boating and fishing §.
Minuses
Dams decrease the natural runoff from watersheds. Less sediment washes
downstream to replenish coastal wetlands and beaches. Salt levels rise
at river mouths, as less fresh water flows out. Dams interfere with
migration routes and spawning grounds, and water released after long
periods behind dams is often oxygen- poor and polluted §.
[LINK] Bonneville Dam, completed in 1938
Before the 56 Columbia River dams were built for irrigation and
hydroelectric power, 16 million wild salmon swam upriver each year.
Today, streams and tributaries yield only 2.5 million salmon, most
bred in hatcheries §.
photo © Gary Braasch/Woodfin Camp & Associates
What lowered water levels do
[LINK] San Joaquin/Sacramento Delta, San Francisco Bay
More than a hundred dams and water-diversion systems built to provide
irrigation and reclaim cropland have transformed the watersheds that
feed San Francisco Bay. Water withdrawals have depleted the San
Joaquin River's flow by up to 90 percent §.
Salinity has spread into the delta §. Combined losses of salmon,
striped bass, shad, and other estuarine fisheries have exceeded $3
billion. Control structures have been built to reduce the amount of
salt water entering the delta.
photo © California Department of Water Resources
[LINK] Aswan High Dam, Nile River, Egypt, 1983
In the early 1960s Egypt dammed the Nile to generate electricity and
provide year-round irrigation for agriculture §. During droughts, the
Aswan High Dam diverts up to 95 percent of the Nile's normal water
flow, holding back silt §.
The dam has deprived the Nile Delta and Mediterranean shores of more
than 1 million tons of nutrient-rich silt §. Sardine and shrimp
fisheries in the southeastern Mediterranean have declined sharply.
photo © Robert Caputo
More Information
* Nubia: Its Glory and Its People - a selection of objects recovered
over twenty years ago by the Oriental Institute Nubian Expedition
in the effort to rescue archaeology from the rising water behind
the Aswan Dam.
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Remedies
San Francisco Bay fish win one
Early in 1993, California and federal authorities imposed a new
balance among the water demands on the enormous San Joaquin-
Sacramento Delta that feeds fresh water into San Francisco Bay.
[LINK] San Joaquin/Sacramento Delta, San Francisco Bay
New regulations sharply reduce pumping from the estuary system during
fish migrations.
photo © California Department of Water Resources
Water savers save water for wildlife
Conserving water frees up more water for wildlife. Water- efficient
toilets, shower heads, and faucets reduce domestic water
consumption--a good thing, since flushing, bathing, and hand-washing
use more than three-quarters of the water in a typical American home.
[LINK] Traditional toilets turned in under a rebate program, Los
Angeles, 1993
Although Los Angeles County spent $100 for each turned-in toilet, the
state will save millions of gallons of water as residents switch to
low-flow toilets that use less than 2 gallons per flush.
photo © Rick Rickman/National Geographic Society
Field flooders turn the tap down
Above-ground irrigation systems waste nearly two-thirds of the water
they use because of evaporation and seepage. Since nearly 70 percent
of water used in the U.S. goes for agriculture, that's a lot of water
lost. Drip irrigation from buried plastic tubing takes water directly
to roots, uses far less water than conventional field-flooding, and
minimizes salt build-up from evaporation that can ruin traditionally
irrigated fields.
[LINK] Subsurface drip irrigation developed by USDA scientist Claude
J. Phene
Although drip irrigation systems are expensive to install, they are a
good investment. Farmers have doubled their yield with only half the
water other growers use.
photo © James A. Sugar
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More Information:
* The Dam and Reservoir Impact and Information Archive
[LINK] Ocean Planet Exhibition Floorplan
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[LINK] gene carl feldman (gene@seawifs.gsfc.nasa.gov) (301) 286-9428
Judith Gradwohl, Smithsonian Institution (Curator/Ocean Planet)