Measurements and spellings are British - but you will get the point. I have highlighted some passages that particularly make the point.
Cry me a river
It was one of the world's great
rivers, but today the Rio Grande is reduced to a feeble trickle. What does its
plight say about our abuse of our most precious resource - water? By Fred
Pearce
Fred Pearce
Monday February 27, 2006
They serve a strong brew at the Alamo
coffee-house in Presidio, a small farming town near the US-Mexican border. They
need to. Times are tough, says Terry Bishop, looking up from his second mugful.
This land, next to the Rio Grande in Texas, has probably been continuously
farmed for longer than anywhere in America, he says. Six hundred years minimum.
It has been home to scalp-hunters and a penal colony; it has seen Comanche
raids, Spanish missionaries, marauding Mexican revolutionaries and a population
boom during a recent aliens amnesty. All that time, it has been farmed. But
soon it will be back to sagebrush and salt cedar. Climbing the levee by the
river at the end of his last field, Bishop shows me the problem. The once
mighty Rio Grande is now reduced to a sluggish brown trickle.
In its middle stretches, the river
often dries up entirely in the summer. All the water has been taken out by
cities and farmers upstream.
"The river's been disappearing
since the 50s," says Bishop, who has farmed here virtually all that time.
There has not been a flood worthy of the name since 1978. For 300km upstream of
Presidio, there is no proper channel any more, he says. They call it the
forgotten river. Bishop's land brings with it legal rights to 10m cubic metres
of water a year from the river - enough to flood his fields to a depth of more
than a metre, enough to grow almost any crop he wants. But in recent years he
has taken only a quarter of that. Even when he gets water, "it's too salty
to grow anything much except alfalfa."
But that is all a bit academic now.
Yields got so low that the farm went bust. Bishop lets some fields to tenants,
but most of them lie idle these days. The land is gradually returning to
desert. And Bishop drinks a lot of coffee. This is the way of things in
Presidio. The town was once a major farming centre. It used to ship in
thousands of Mexican workers to harvest its crops. Bishop's farm alone once
employed 1,000 people. But that has all ended and the unemployment rate among
the town's permanent residents is almost 40%.
The only profitable business now is
desert tourism. An old silver mine a few miles up the road has been turned into
a ghost town, and a fort at Cibolo Creek is now an upmarket resort attracting
the likes of Mick Jagger. Harvesting tourists, that's the game now, says
Bishop.
On the map, the Rio Grande is the
fifth longest river in North America and among the 20 longest in the world. Its
main stem stretches 3,000km (1,900 miles) from the snowfields of the Colorado
Rockies to the Gulf of Mexico, via New Mexico and Texas. It drains one tenth of
the continental US and more than two-fifths of Mexico. The hub of human exploitation of the Rio Grande is
the Elephant Butte reservoir near El Paso in Texas (about 300km upstream of
Presidio). It was built in 1915 and changed the river for ever. The
wild, untamed flow - which obliterated villages and once rode right through
downtown Albuquerque - was ended for good and its waters were corralled for
irrigation.
Today, Elephant Butte and its downstream sister, the Caballo,
all but empty the river to supply El Paso and nearby farmers. More than 9
million people in the basin rely on the Rio Grande's waters. But it is the
farmers who make most use of it. Four-fifths of the water in the river is taken
for irrigation - most of it to grow two of the thirstiest crops in the world:
cotton and alfalfa, a grain fed to cattle. And the wastage is huge. Only about
40% of the water reaches the crops, while evaporation in the hot sun takes more
than two metres of water a year from the reservoirs - a total of around
300m cubic metres from Elephant Butte alone.
Usually a trickle of water gets
through to the sea. But since the mid-1990s, a decade during which drought has
gripped the basin, the flow has been at record lows. In 2001, it ceased
altogether. A sandbar 100m wide completely blocked off the river from the Gulf
of Mexico. The bar lasted for five months before summer flows washed it away.
And for much of the next two years it returned. You could drive a car across
the beach between the US and Mexico. The Rio Grande had, literally, run into
the sand.
Rivers so often define our world. Is
there a better book about America than Huckleberry Finn's journey on the
Mississippi? Is there a better way of seeing London than taking a boat down the
Thames to Greenwich? Some of the greatest human adventures have been along
rivers: up the Orinoco to find El Dorado; or the search for the source of the
Nile. Millions of Indians keep bottles of Ganges water in their homes, like
holy water. We romance on the Blue Danube and the Seine; and fight over the
Jordan and the rivers of Babylon. Yet something disturbing is happening.
The
maps in an atlas no longer accord with reality: inland seas and lakes are
disappearing; the old geography lessons about how
rivers emerged from mountains, gathered water from tributaries and finally
disgorged their bloated flows into the oceans are now fiction. Some of the great rivers of the
world are disappearing: the Nile in Egypt, the Yellow River in China, the Indus
in Pakistan, the Colorado and Rio Grande in the US - all trickling into the
sand, sometimes hundreds of miles from the sea. Few of us realise how
much water it takes to get us through the day. On average, we drink around five
litres of the stuff. Including water for washing and for flushing the toilet,
western Europeans use only about 150 litres each. In some countries suburban
lawn sprinklers, swimming pools and sundry outdoor uses can double that figure.
Typical per-capita water use in suburban Australia is 350l and in the US around
400l.
We can all save water in the home. But
laudable though it is to take a shower rather than a bath, put a brick in the
lavatory cistern and turn off the tap while brushing our teeth, we shouldn't
get hold of the idea that regular domestic water use is what is really emptying
the world's rivers.
Manufacturing the goods that fill our
homes consumes a certain amount, but that is not the real story either. It is only when we add in the
water needed to grow what we eat and drink that the figures really begin to
soar. The numbers are mind-boggling: it takes between 2,000 and 5,000l
of water to grow one kilo of rice. That is more water than many households use
in a week. For just a bag of rice.
It takes 1,000l to grow a kilo of
wheat, and 500l for a kilo of potatoes. When you feed grain to livestock for
animal products such as meat and milk, the figures become yet more startling.
It takes 11,000l to grow the feed for enough cow to make a quarter-pound
hamburger; and between2,000 and 4,000l for that cow to fill its udders with a
litre of milk. Cheese? A kilo of cheddar or brie takes about 5,000l.
As a typical meat-eating,
milk-guzzling westerner, I consume as much as a hundred times my own weight in
water every day. It is time, surely, to preach the gospel of water conservation
- but don't buy one of
those T-shirts with jokey slogans such as "Save water - bath with a
friend". Good message, but you could fill 25 bath tubs with the water
needed to grow the 250 grams of cotton used to make the shirt. Globalised markets mean that whenever
you buy a T-shirt made of Pakistani cotton, eat Thai rice or drink coffee from
Central America, you are influencing the hydrology of those regions - taking a
share of the river Indus, the Mekong or the Costa Rican rains. You may
be helping rivers run dry. The consequences are with us already. Back in Texas,
the El Paso Times regularly alerts readers to the days when they can use public
water on lawns, and the days they can't.
Jittery suburbanites are repairing old
wells in the hope of capturing some private water from beneath their land. And
in the unplanned shanty-town "colonias", where many Mexicans end up
after crossing the river, thousands of people live without access to piped water
at all - and that is a shock to find in the US, even in the desert. El Paso is buying up properties
from local farmers to bag their rights to underground water reserves. Its
"water ranches" are dotted all along the highway to Presidio, to
exploit the subterranean aquifers - natural reservoirs of water trapped between
layers of rock. But water-ranching will be only a temporary solution. The region's major aquifer, which lies
beneath a vast area of Texas, New Mexico and the Mexican Chihuahua desert, is
rapidly running dry because there is not enough rain to replace what is pumped
out.
According to Mary Kelly, a leading
environmentalist campaigning to save the river, pumping out this underground
water could trigger the final and irreversible desiccation of the landscape.
"Most of the recharge for the aquifer comes from seepage from the canals
supplying the farms - which ultimately means it comes from the Rio
Grande."
Downstream of El Paso, the river
becomes a dribble of sewage effluent disappearing into remote scrub most of the
way to Presidio. Hydrologically speaking, the Rio Grande pretty much ends here.
Beyond Presidio, the river winds through dramatic canyons in the Big Bend
National Park. But the flow is small and muddy. "We get about a sixth of the
historical flow here," Dave Elkovitz of the park authority told me. A
couple of weeks before my visit, the river dried up here for the first time in
more than 50 years. Stagnant pools of water evaporated, leaving dry gravel beds
and thousands of dead catfish. Starved of food, a troop of black bears headed
back to Mexico. "We have treaties for the river," said Elkovitz.
"But they allocate more water than actually exists. What good is
that?"
The main treaty, signed in 1944,
requires that one-third of the water flowing into the Rio Grande from six
Mexican tributaries, much the largest of which is the Rio Conchos, is allocated
to the US. The US can dry up the Rio Grande at El Paso as much as it wants,
but, come hell or low water, the Mexicans have to deliver that quota. The
treaty might have been fine 60 years ago when the rains could be relied upon,
but what it means now is that northern Mexico is littered with irrigation areas
living on borrowed time and water they owe to Texas.
Today, these districts are engaged in
a major modernisation process to save water. Engineers are busy lining canals
to prevent water seeping out of their porous bottoms. And they are installing
perforated rubber piping to get water right to the plant roots rather than
flooding fields. This $130m programme is being paid for mainly by the US
government: the aim is to save 350m cubic metres of water a year. That volume
close to the amount that Mexico should be sending down the Rio Conchos into the
Rio Grande each year under the treaty terms.
"The Americans will get what we
save," said one official. It sounds like a win:win situation: the Mexican
farmers, I was told, would get greater water security, while the US gets its
missing water. But there is a fallacy here: the modernisation will not actually
make more water, and most of the savings are not real savings. The seepage will
stop, but, says Kelly, that only means the aquifer will no longer be
replenished.
As
the canal water has failed in recent years, many farmers have come to rely on
pumping underground water. But most of the underground water in the wells comes
from seepage from the canals and fields. If the seepage is cut, the wells will
dry up. According to Kelly, the modernisation plan will only hasten the
aquifer's demise. The local irrigation engineers, and the people funding
their work, seemed unconcerned by this prospect. But the tragedy is that to
meet their immediate obligations to deliver water to Texan farmers, the
Mexicans risk the loss of their vital underground water reserves.
Thanks
to global trade, this is a scenario being played out the world over. Economists call the water involved in the growing and manufacture
of products "virtual water". Every tonne of wheat arriving at a
dockside, for example, carries with it in virtual form the 1,000 tonnes water
needed to grow it. The
world's virtual water trade is estimated to amount to be about 1,000 cubic
kilometres a year, or 20 river Niles. Of that, two-thirds is in a huge
range of crops from grains to vegetable oil, sugar to cotton; quarter is in
meat and dairy products; and just a tenth in industrial products. This trade
"moves water in volumes and over distances beyond the wildest imaginings
of water engineers," says Tony Allan of the School of Oriental and African
Studies in London, who invented the term "virtual water".
This
hidden water export business is laying the fuse for a hydrological time-bomb.
Mexico's virtual-water exports are emptying its largest body of water, Lake
Chapala, which is the main source of water for its second city, Guadalajara. But the biggest net exporter of virtual water the US. It exports
around a third of all the water it takes out of the natural environment. Much
of that is in grains, either directly or via meat. The US is emptying critical
underground water reserves, such as those beneath the High Plains, to grow
grain for export. It also exports an amazing 100 cubic kilometres of virtual
water in beef. Once upon a time, it was the cattle drives that made the Rio
Grande famous in scores of westerns. One day soon, the movie house may be the
only place you can find the river at all.
Another good Pearce book to read is Confessions of an Eco-Sinner: Tracking down the sources of my stuff.
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