April
2001
Less
is More: Making Changes and Saving Water
The Satya Interview
with Sandra Postel
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For the past two decades, Sandra Postel has
dedicated her career to issues pertaining to the Earth’s fresh
water. She is the Director of the Global Water Policy Project, which
promotes the protection and sustainable use of the world’s water
resources, and is a Senior Fellow of the Worldwatch Institute. Postel
is the author of Pillar of Sand: Can the Irrigation Miracle Last?
(Worldwatch/Norton, 1999) and Last Oasis: Facing Water Scarcity
(Norton, 1997). Here she tells Angela Starks about the problem
of water scarcity, the role of agriculture, and the importance of adjusting
our consumption habits.
It’s easy for us in the West to think of water as an infinite
resource; but there’s a serious problem with water scarcity isn’t
there?
The degree of water scarcity we now see around the world is staggering.
So many rivers are running dry during the times of the year when the
water is needed most and so many places are over-pumping their groundwater
to meet current needs. How are we going to produce the food that we’re
going to need in the future if we’re over-pumping water, if we’re
using groundwater unsustainably today?
The main shift that I’ve been talking about for quite some time
is the need to begin using water a lot more efficiently and figuring
out how to get more benefit out of every liter of water that we take
from the natural environment. We’ve basically tried to take as
much water as we desire by building large dams, diverting river water,
levying rivers and so on, and that has created a lot of degradation
of rivers, wetlands, deltas and all kinds of aquatic systems. We’re
destroying the very systems that we are dependent upon.
Are there any means by which we can meet the growing demand for water
without further damaging the environment and the integrity of natural
water systems?
We need to look at how we can satisfy our food needs, our material
needs, our household water needs—basically all of our needs for
water—in a more efficient way. That entails more than just installing
low-flush toilets and low volume shower heads; it involves looking
much
more at our overall consumption levels because everything that we buy,
use, and eat requires water to produce, and at the same time the waste
products that we create from our heavy consumption is polluting the
water.
There are certainly technologies out there that we can make better use
of, from more efficient household fixtures to more efficient sprinklers
in agriculture. Even something like natural, native landscaping instead
of insisting on perfect green lawns saves enormous amounts of water.
Those kinds of changes would buy us time to make the harder adjustments
we should be making. For example, if we want to do something at the
personal level, looking at the diet is a perfect place to start. The
American diet takes two to three times more water to produce than the
average diet of someone in, say, India.
Given that water scarcity may be the biggest threat to global food
security, and since a huge percentage of the world’s irrigated
crops simply end up as livestock feed, would the widespread adoption
of a vegetarian diet make a difference?
Eating higher up the food chain is a more water intensive diet because
of the meat consumption, so I think the adoption of a vegetarian diet
would make a difference, certainly in Western countries. And ultimately
that may have helpful effects globally as well. Right now, I don’t
know if a low-meat diet will do a whole lot for someone who is hungry
in India, but over time, yes.
You suggested eating lower down the food chain. Given that this
won’t
occur overnight, is it a matter of improving the water productivity
in the meantime, while adjusting to more frugal consumption habits?
Yes. Though I’m not inclined to be preachy about diet, I think
as people become more aware of the consequences of their actions and
the choices they do have, more people may voluntarily start to make
those choices for themselves.
I also think as a mater of public policy it’s very important for
the prices of the goods that we purchase—whether it’s computers,
clothes or meat—to reflect the true cost, including the cost to
the environment. So if we’re depleting groundwater to grow grain
to feed to livestock, but that is not incorporated in the price of the
hamburger, that can’t possibly include the full cost of that production
cycle. And until prices start telling us the truth we won’t start
making the right decisions.
Can you give examples of any promising projects or initiatives that
are helping to solve the water crisis?
Some of the most interesting and exciting ones that I’ve seen
personally have to do with the spread of simple irrigation technologies
for very small-scale, poor farmers. One example is a technology that’s
spreading in Bangladesh. It’s called a Treadle Pump, a human-powered
irrigation pump that allows a farmer who otherwise might not have access
to irrigation water to draw from very shallow depths. In Bangladesh
they’ve been selling them for only about $35 each so a farmer
can afford to purchase one. It typically pays back within one season,
because
the farmer is able to irrigate a higher value rice crop, plus grow
some vegetables. The family that was previously going hungry for part
of
the year is now not only well fed but they also have increased income
from taking some of their produce to market.
Is there a place for biotechnology in this water crisis, such as
designing more water-efficient plant varieties? And are such solutions
worth it, given the dangers of genetic engineering (GE)?
I think there will be efforts to develop crop varieties that are
more salt tolerant, more water efficient to the extent that that’s
possible, and more drought resistant. As for exactly how we go about
that, we’ll have to see what turns out to be most productive.
There are very valid concerns about GE crops. However, there’s
also the possibility of using genetic techniques to enhance conventional
breeding. Being able to identify the presence of genes within a crop
variety can short-circuit some of the laborious conventional breeding
processes and focus in on exactly the genes that enhance a given trait
that you desire. In this way, there’ll be no need to introduce
genes from one species to another. We could continue with our usual
breeding practices but more selectively and more efficiently.
During the green revolution stage when we were trying to increase the
yield of particularly rice and wheat, more of the crops’ energy
was basically bred to go into the actual grain instead of ending up
in the overall biomass and the parts we don’t eat.
What other agricultural changes could make a difference?
Agriculture is by far and away the biggest user of water, so I would
emphasize the need to begin moving toward a much more efficient agricultural
economy. For example, we need to use irrigation water more efficiently,
and to explore possibilities of recycling waste water for use in irrigation.
In some ways I prefer the term water productivity rather than water
efficiency because we need to be thinking much more broadly about how
we maximize our benefit from the water we’re taking from nature.
So we shouldn’t be talking so much about how much yield per unit
water we’re getting. We should be talking more about how much nutrition
per unit water we’re getting. It’s a much broader concept
but it really gets at the heart of the direction we need to move in.
You can irrigate sugar cane efficiently, but the real point is: do we
need to be growing sugar cane? So I think we need to go deeper than
the efficiency question, important as it is. Sure, it can be the initial
line of attack, to irrigate your crop as efficiently as possible, but
beyond that we need to ask: is that the right crop to be growing? Do
we really need to be eating the diets we’re eating? Do we really
need to be wearing the clothes we’re wearing? Do we need to be
buying as many things as we’re buying? How can we increase the
real value of the water we’re extracting from nature, realizing
that every inefficient and unproductive use we make of water has a
very
serious ecological cost attached to it? Water is not free anymore.
Every additional unit we take out of the natural environment has a
bigger
and bigger cost to nature and the ability of nature to do its work
and we have to recognize that cost every time we decide to take more
out
of it.
To learn more, visit www.worldwatch.org
or call (202) 452-1999.
