The New York Times
Los Angeles, City of Water
By JACQUES LESLIE
usurpation of water hundreds of miles away to slake the thirst of its ever-expanding population. As a character in “Chinatown,” the noirish 1974 film starring Jack Nicholson that churns through the city’s water history, puts it, “Either you bring the water to L.A., or you bring L.A. to the water.”
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Los
Angeles’s shift occurred out of necessity, after legal decisions in the
1990s forced it to give up some of its imported water. More and more
cities now face water constraints. In the West, where most climate
scientists expect droughts to lengthen and deepen, the techniques being
introduced in Los Angeles ought to be viewed not just as smart choices,
but as requirements.
Though
most projects will start too late to address the severe drought now
plaguing much of the West, they show how to cope with future ones.
Together, these projects will treat polluted and even sewage water,
capture rainwater, store water in aquifers, and use (or reuse) all of
it, often while mimicking or supporting natural processes. The area’s
water administrators who, until recently, thought of watersheds as
merely rural concerns now recognize that even in Los Angeles, all living
things are linked by their common water course and that its proper
management is essential to the administrators’ success.
In
the last decade the tenets of sustainable watershed management have
spread across the country. The city of Los Angeles still imports 89
percent of its water, a proportion that underlines the severity of its
water needs, but dozens of other cities (including some Eastern ones)
are embracing pieces of Los Angeles’s water sustainability approach.
San
Francisco has become a leader in using recycled wastewater for
nonpotable purposes like toilet flushing and gardening while reducing
its per capita water use to 46 gallons a day, one of the lowest rates in
the nation. San Antonio has developed a multifaceted conservation
program that has cut the city’s per capita water use by nearly half over
the last two decades. Even Philadelphia, which usually has ample water,
committed itself in 2011 to a $1.2 billion green infrastructure program
that uses storm water capture to prevent environmental degradation.
These efforts share the basic tenet that all the water in any watershed —
whether tap water, groundwater or toilet water — must be considered
part of a constantly circulating hydrological whole.
Los
Angeles gets little rain, and what it does get occasionally arrives in
the form of harsh, flood-generating storms, like the ones last week.
After numerous destructive floods in the first third of the 20th
century, the Army Corps of Engineers and the city’s public works
department began building a flood-control infrastructure. It was
designed to move storm water quickly off city streets and into the
Pacific Ocean. All but seven miles of the 51-mile-long Los Angeles River
was turned into an ugly concrete conduit that is usually empty.
By
the late 1980s, storm water quantities were getting so high that the
flood-control channels could no longer contain them. The authorities
assumed their only alternative was to raise the cement walls still
higher, which they did in the 1990s at a cost of $180 million.
Meanwhile,
two environmental campaigners, Dorothy Green of Heal the Bay and Andy
Lipkis of TreePeople, were telling anyone who would listen that the
flood-control infrastructure should be reorganized to capture water, not
cast it into the sea. If storm water is harvested and directed into
aquifers, they argued, floods can be prevented. Then the stored water
can be pumped when needed, treated and consumed.
To
prove his point, in 1998 Mr. Lipkis’s nonprofit retrofitted a house in
South Central Los Angeles, then staged a mock flood. The house’s roof
was lined with gutters that fed rainwater into two 1,800-gallon
cisterns, and the lawns in the front yards and backyards were lowered
six inches to form a wetland. On the big day, local officials watched
from beneath umbrellas as a 4,000-gallon water truck dumped around 15
tons of water on the roof, yet none of it left the premises.
The
property functioned instead as a miniature watershed, storing water for
outdoor use or absorbing it and redirecting it to an aquifer below.
Flood-control officials were so impressed that they dropped a $42
million proposal they had been considering for a storm drain in a highly
flood-prone section of the San Fernando Valley called Sun Valley and
instead introduced a plan to test storm water capture there.
Under
the stewardship of the Council for Watershed Health, a local nonprofit,
six local government agencies responsible for water supply, water
quality, floods and groundwater worked with academic researchers and the
United States Bureau of Reclamation, the federal agency once known as
the West’s leading dam builder, to retrofit an entire Sun Valley city
block. The officials chose Elmer Avenue, a street so flood-prone that
routine storms turned it into a river.
Completed
in 2010, the $2.7 million project enables residents to collect
rainwater on their rooftops and divert it to rain barrels for later use.
Water that overflows the rain barrels spills into spongelike rain
gardens that replaced grass lawns. Further overflow seeps through
permeable driveways or is conveyed by drain to a swale of rocks, soil,
plants and mulch running the length of the sidewalks.
The
street itself was excavated, filled with a six-foot-deep layer of
gravel fed with rainwater through large perforated pipes and topped with
pavement; in an average rain year, that expanse should collect enough
water for 80 houses, not just the 24 retrofitted ones. As the water
slowly drips into the aquifer below, it is cleansed of pollutants it
collected on the street. By encouraging natural processes that perform
ecological services, the project simultaneously mitigates flooding,
pollution and water scarcity.
Production
of water like that captured on Elmer Avenue costs $300 an acre-foot,
while Los Angeles now pays $800 to $1,000 an acre-foot for imported
water. According to a study conducted by the Pacific Institute and the
Natural Resources Defense Council, a fully developed storm-water capture
system in greater Los Angeles could add 309,000 acre-feet per year to
water supplies, more than half of Los Angeles city’s annual current
consumption of 587,000 acre-feet per year.
The
demonstration projects persuaded Los Angeles officials last year to
adopt an ambitious 20-year plan that treats the Los Angeles basin as a
single watershed, integrating water quality, water supply, flood
control, wastewater, parks and habitat programs. However, given the huge
retrofit the plan requires, the program is still in its infancy. It
enjoys backing from the state, which as early as 2002 enacted
legislation embracing integrated watershed management, and last month
Eric Garcetti, the mayor of Los Angeles, underlined the city’s shift to
local water by issuing a directive to cut purchases of imported water by
half within a decade. Even so, implementation is far from assured.
“Governance
is probably the biggest obstacle to a sustainable water supply,” Mark
Pestrella, who heads flood control for the Los Angeles County Public
Works Department, told me.
A
2014 study by the geographers Miriam A. Cope and Stephanie S. Pincetl
at the University of California, Los Angeles, found that more than 100
entities in Los Angeles County — private utilities, nonprofit water
companies, cities and an assortment of “special districts” — conveyed
water; simply identifying and classifying them took the researchers more
than a year. Some are tiny and will face pressure to consolidate. And
some — agencies with a designated mission like sanitation or flood
control — may be impeded by the Los Angeles city charter from
participating in multipurpose projects. Even if they can, they will
undoubtedly find it hard to cede some of their authority to carry out
multipurpose, multiagency projects. So far most money for the projects
has come from government grants and voter-approved bond measures, but
new sources must be found for the vastly larger sums the projects
require.
Even
so, what has already happened in Los Angeles is something rare: a
straightforward environmental victory. Environmentalists diagnosed a
major problem and outlined its solution, and government officials
eventually accepted their approach.
Strangely,
many, if not most, Angelenos are oblivious to the region’s pathbreaking
role. Like everyone else, they think of Los Angeles as a water
extorter, and don’t realize that its current path is the sincerest form
of atonement.
Jacques Leslie is the author of “Deep Water: The Epic Struggle Over Dams, Displaced People, and the Environment.”
A version of this op-ed appears in print on December 7, 2014, on page SR1 of the New York edition with the headline: Los Angeles, City of Water. Order Reprints| Today's Paper|Subscribe
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