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- Due to the worldwide
decline in freshwater availability, a need for a solution is imperative.
Many experts believe they know the route that should be taken to
solve the problem. As population increases so does the demand for
freshwater, and despite the on-going hydrologic cycle, the replenishing
rate cannot keep up with the rate of consumption. Water is being
utilized for industries, agricultural uses, and the common household.
This page examines the use of technology to increase the supply
of freshwater. Some of the main methods that have been proposed
include the towing of icebergs, seeding of clouds, and desalination.
Iceberg
Towing
A longstanding proposal
has been to tow icebergs from Antarctica to supply freshwater. In
1978 the idea of towing icebergs to the U.S. to provide freshwater
was endorsed by the California State Senate. The plan was to have
these 'iceberg trains' driven by electric propellers and powered
by a floating nuclear plant (Redmond, 1993). A similar procedure
had already been carried out in southern Chilean ports during the
early 1900's. (Charlier, 1991). However, the extremely expensive
costs, and 80% loss of volume during the towing route cast a shadow
over the concept. In the late 1950's, a oceanographer named John
Isaacs suggested the icebergs be brought into Los Angeles. The plan
was never carried out. However, for almost the last 30 years, Terry
Spragg has been working on the iceberg project. In 1991 he had planned
a test run but was running into complications with funding and a
lack of workers (Wohleber, 1991). Interest in iceberg towing has
also been expressed by wealthy oil-rich desert countries such as
Saudi Arabia.
http://www.mmass.co.uk/images/HughDunlop4.jpg
Cloud
Seeding
Cloud seeding
is a process in which dry ice or potassium iodide particles are
used to increase rainfall. Recent research has shown that hydroscopic
salts have been the most successful in increasing the amount of
rainfall. The chemicals are sprayed over a propane flame and float
into the clouds. Although there was no scientific proof found by
a national study that seed clouding works, the general public who
are faced with water shortages are still willing to try it. In fact,
the Denver Water Department in Colorado has spent hundreds of thousands
of dollars on cloud seeding. In 2001, an estimated 66 cloud seedings
took place (USA Today, 2003). Despite the current use of the cloud
seeding process, many still feel that more research is essential.
There is also some fear that mismanaged cloud seeding could backfire.
Some South Dakota residents blame cloud seeding for a torrential
rainfall and deadly floods in Rapid City in 1972.
http://www.msnbc.com/local/wnyt/Images/030603_wnyt35.jpg
Desalination
Desalination is the
process of removing the salt impurities and other dissolved minerals
from bodies of water. When it is removed from the oceans and has
a high salt content it is called "seawater." When the
water that is retrieved is less salty than seawater, but has a higher
salt content than fresh water it is considered to be "brackish
water." Desalination may be accomplished through the use of
heat (thermal) or of a semi-impermeable membrane. Thermal desalination
is a process in which the salty water is heated, the evaporation
collected, and then allowed to cool and condense where it as pure
water. The semi-impermeable membrane, also known as Reverse Osmosis
(RO), is the primary choice for the desalination of brackish water.
The process involves sending the salty water through a film membrane
at a pressure of 1,000 to 1,500 per square inch, resulting in one-third
of the water having a low salt content.
Currently
about 3,500 desalination plants dot the globe, with most located
in higher developed countries. It is important to remember that
all countries are being faced with water depletion and only a few
are able to set funds aside for desalination research and technology.
Israel has set up the Grand Water Research Institute (GWRI) which
is funded by the American Technion Society. Israel, as well as neighboring
countries and territories, has begun to feel the stress from the
lack of water resources as populations continue to grow. Because
of the over-pumping that has taken place in Israel, saltwater intrusion
has occurred along the Mediterranean coast, resulting in a 20% loss
of useable drinking water from the underground aquifer. The Rabin
Desalination Laboratory, led by Professor Rafi Semiat and aided
by Professor Emeritus David Hasson, has been set up by the GWRI
to conduct research. The main objectives of this lab are to not
only concentrate on reducing the high costs of (R.O.) technology,
but to continue investigating techniques to raise the efficiency
of all desalination methods. A promising step taken to reduce the
amount of freshwater use has been to recycle wastewater through
agricultural irrigation. However, the lack of freshwater is still
a pressing problem.
The United
States, unlike many countries, has the resources and funds to investigate
and research the water depletion problem. A federal agency called
the U.S. Bureau of Reclamation has a division called ‘The Water
Supply, Use, and Conservation Group’ is in charge of the following
technical related functions:
1. Conducting hydrologic investigations and studies including participation
on matrix and negotiation teams;
2. Providing reclamation- wide technical guidance on hydrologic
studies;
3. Reviewing studies and reports containing hydrologic information
to ascertain technical adequacy;
4. Developing technical standards and guidelines for hydrologic
analyses and studies;
5. Developing and applying improved procedures for hydrologic data
collection, retrieval, and analysis;
6. Assisting other agencies and governments with technical training
and conducting hydrologic investigations and studies; and
7. Conducting research into new methodology for hydrologic investigations
and analysis.
The issues
involved with the depletion of water will never be solved merely
though a technical "fix." No matter how many technical
advances are made (and resources are continuously being discovered),
we cannot change our need for water. We have to share that need
with many plants and animals that we depend upon, and people need
to distribute water more equitably, prioritizing those who need
it the most for their lives. Water is going to continue to disappear
and the price of research is going to continue to be expensive.
Sadly, we are going to continue to see many lesser developed countries
become more deprived as the price for freshwater grows beyond their
reach. Whatever the best solution is to the problem, and even if
the price is attainable, the most advantageous goal would be to
conserve what we already have.
Sources
For
more information:
US
Bureau of Reclamation
MSNBC
article
Definition
of Israel's Water Problems
The
Stephen & Nancy Grand Water Research Institute: Israel Institute
of Technology
http://www.wws.princeton.edu/cgi-
bin/byteserv.prl/~ota/disk2/1988/8842/884203.PDF
Redmond,
T., and Mowrey, M., October 1993, Unnatural Disasters: The ten
worst environmental ideas in U.S. history: Omni, vol. 16, issue
1.
Charlier,
R.H., 1991, Water for the desert- A viewpoint: International Journal
of Environmental Studies, vol. 39, p 11-35.
Wohleber,
C., 1991, L.A. Thaw: Omni, vol. 13, issue 11.
West
seeks help in cloud seeding: USA Today, December 2, 2003, p. 3a.
Hecht,
J.L., 2002, Salty Solution: Christian Century, vol. 119, issue
13.
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