The
Drying Of The West
Drought
is forcing westerners to consider wasting less water.
23
Febraury, 2014
THE
first rule for staying alive in a desert is not to pour the contents
of your water flask into the sand. Yet that, bizarrely, is what the
government has encouraged farmers to do in the drought-afflicted
south-west. Agriculture accounts for 80% of water consumption in
California, for example, but only 2% of economic activity.
Farmers
flood the land to grow rice, alfalfa and other thirsty crops. By one
account, over the years they have paid just 15% of the capital costs
of the federal system that delivers much of their irrigation water.
If water were priced properly, it is a safe bet that they would waste
far less of it, and the effects of California’s drought--its worst
in recorded history--would not be so severe.
The
"ridiculously resilient ridge," an unusually persistent
high-pressure zone, has installed itself off the Pacific coast,
stopping precipitation systems from travelling toward the Sierra
Nevada Mountains, where they typically deposit their moisture. Last
month snowpack in the Sierras fell to 12% of average January levels.
Rainfall has disappointed for three years. Lake Folsom, near
Sacramento, has shrunk so far that an old gold-rush town has been
exposed. The rainy season has six weeks or so to go, but there is
little sign of respite. California is bracing itself for a brutal
fire season.
The
Economist
State
officials have cut off supplies to water districts; their federal
counterparts will soon follow suit. Some farmers who made the risky
decision in past years to plant lucrative pistachio and almond trees,
which require year-round watering, have had to bulldoze them. Others
are fallowing farmland, or digging deeper to tap brackish
groundwater, further depleting aquifers.
On
January 17th Governor Jerry Brown urged Californians to cut water use
by 20% and issued a drought declaration, which loosens the rules
restricting in-state water transfers. Last week Barack Obama visited
Fresno, in California’s fecund Central Valley, to announce $183m of
federal aid before spending three days golfing on well-watered
courses in the desert. This week California’s leaders pledged a
further $687m in drought relief.
Drought
is also afflicting California’s neighbours to the east (see map).
But they, along with California, are grappling with a longer-term
problem: the Colorado river, which waters seven states (plus part of
Mexico), is struggling to service its clients. Thanks to declining
flows, last year the Federal Bureau of Reclamation (FBR), which
oversees its use, cut the release of water from Lake Powell on the
Arizona-Utah border to Lake Mead, America’s largest reservoir. It
has never done this before.
The
rules are showing their age. The law of the river, which allocates
precise amounts of water to the seven Colorado-basin states, was
signed in 1922. The region has grown quickly and unevenly since then
but the law has proved resilient; states used to sue each other with
wearying frequency but now work together well.
The
problem is that 1922 fell in an unusually wet period. For decades
that did not matter; the basin states were not big enough to demand
their full allocation. No more: five of the seven are among America’s
ten fastest-growing states. Moreover, climate change may be reducing
supply even as demand rises. In 2012 the FBR said that by 2060 the
supply gap from the Colorado could reach 3.2m acre-feet (an acre of
water a foot deep is the standard unit for large amounts of the
precious liquid).
Traditionally
the West has tried to engineer its way out of water problems, and
that approach is not dead in Nevada. Greater Las Vegas, where most
Nevadans live, depends on Lake Mead for 90% of its water, but before
long the lake is expected to fall below the level of the first of two
pipes that connect it to the city. So officials are building a deeper
$816m "third straw" to maintain supply. They also want to
lay a 300-mile pipeline to bring water from Nevada’s sparsely
populated north to Las Vegas, a controversial plan some compare to
Los Angeles’s removal of water from the Owens Valley 100 years ago
(as fictionalised in Roman Polanski’s "Chinatown").
Unhappily
for Nevada and Arizona, California’s problems are also theirs.
Southern California is entitled to 4.4m acre-feet of Colorado water a
year, mainly for farmland in the Imperial Valley. Under a 2007
agreement the three states may store water they do not need in Lake
Mead for later withdrawal.
Because
of its drought California is now drawing down the 580,000 acre-feet
it has saved in recent years; it took around 80,000 in 2013. That is
hastening the day when Mead falls below 1,075 feet (it is currently
at 1,109) and compulsory cuts kick in. For complex historical reasons
Nevada and Arizona will lose a combined 500,000 acre-feet a year
before California has to give up a drop.
Douglas
Kenney of the University of Colorado Law School predicts "a new
era" of water management. One still occasionally hears grand
talk of transporting water from the Missouri river, or of ferrying
icebergs from Alaska, but these pipe dreams are giving way to a focus
on conservation and reform.
Thanks
to careful planning by water authorities many cities in the West have
slashed per-capita water use; in the past 12 years Las Vegas has cut
consumption by one-third as its population grew by a fifth. Its
successful "cash-for-grass" programme (since renamed after
grumbles from the Drug Enforcement Administration), which pays
residents to tear up lawns, has been imitated elsewhere. All water
used indoors is recycled.
But
more can be done, says Michael Cohen at the Pacific Institute, a
think-tank. Cities in dry places like Israel and Australia still
consume far less water than Las Vegas. Other cities in the West have
a long way to go: half the houses in Sacramento do not meter water;
Palm Springs, close to where Mr Obama teed off this weekend, still
peddles the old illusions of desert verdancy. As for water trading,
it is underdeveloped within states, let alone between them.
Most
of the future growth in water demand is likely to come from cities.
Some therefore argue that urbanites should bear the burden of
reducing demand. This is too kind to farmers, who waste far more.
Crops that cannot be grown without subsidies should not be grown. It
should not take a drought to make people stop building paddy fields
in the sand.
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