CALIFORNIA FOCUS
90405 FOR RELEASE: TUESDAY, JULY 7, 2015, OR THEREAFTER
BY THOMAS D. ELIAS
“LAWN REPLACEMENT: MIXED BAG OF GOOD, BAD EFFECTS”
“LAWN REPLACEMENT: MIXED BAG OF GOOD, BAD EFFECTS”
Listen to water officials from Gov.
Jerry Brown down to local officials and you’d think replacing lawns with
drought-resistant plants or artificial turf is a pure good, no negatives
involved.
They know lawn replacement, often
called “xeriscaping” because it can use cactuses and other desert plants,
generally leads to at least a 30 percent cut in household water use.
But…you could read reports from the
ongoing Women’s World Cup soccer tournament, where ambient temperatures in
cities like Winnipeg and Ottawa were in the high 70s at some game times, but
temperatures on the synthetic grass fields ranged from 120 to 129 degrees.
That’s the “heat island” effect, where
non-grassy surfaces like the faux grass and gravel sometimes used to replace
lawns gather heat from the sun. Unlike grass, they don’t use the sunlight for
anything, so heat energy can pile up and even warm adjacent buildings.
Temperature differentials won’t often be as extreme as at the Women’s World
Cup, but can drive up electricity use and air conditioning bills.
Reports the Accuweather forecasting
service’s blog, “Grassy surfaces will be significantly cooler on a sunny day
when compared to artificial turf, gravel or pavement.”
This is one reason some homeowner
associations are trying to ban replacement of front lawns with synthetic grass,
even as many water agencies pay by the square foot for tearing out existing
lawns. Homeowners often get phone calls from services offering free
natural turf removal and replacement in exchange for signing over those
payments. Some local water agencies, however, refuse to pass along
turf-replacement subsidies for fake lawns using synthetic turf.
There’s also the fact that grass pulls
carbon out of the air. The more green leaf surfaces in any area, the more
greenhouse gases will be absorbed. Which means grass helps fight climate change.
Grassy surfaces also facilitate
recharge of ground water, most water landing on them eventually trickling
down into aquifers. So unless replacement surfaces are extremely porous, more
storm water will eventually run off into the Pacific unused and less will
become ground water.
This all leads to questions about the
efficiency of lawn replacement campaigns now being run by myriad water
agencies. By far the largest of these plans comes from California’s biggest
water provider, the six-county Metropolitan Water District of Southern
California, often called “the Met,” which has a $450 million, two-year
conservation incentive program, aiming to save as much as 80,000 acre feet of
water yearly over 10 years. That comes to $562 per acre foot saved, far more
than the Met pays for most water today.
The most visible and expensive part of
this program is lawn replacement, which will use about three-fourths of the
money to replace 172 million square feet of grass, or 3,948 acres. But lawn
removal is far from the most effective part of the water-saving plan. Much more
will be saved by replacing old fixtures and equipment.
“The device replacement part of our program
should save about 60,000 of those acre feet,” says Jeff Kightlinger, general
manager of the Met. “Devices give a bigger bang for the buck.” The Met is
paying customers to install everything from low-flow shower heads to
high-efficiency lawn sprinklers and a new generation of ultra-low-flow toilets.
The biggest savings may come from new-generation cooling tower controls for
heating and air conditioning units atop large buildings.
And yet, reports Kightlinger, “Almost
all the news reports on our conservation program have focused around turf
replacement.”
Then there’s the fact that many
thousands of acre feet of water are wasted by over-watering grass and trees.
“Commonly used shrubs, trees and grasses have a lot of drought tolerance,” says
Dennis Pittenger, Riverside-based environmental horticulturist for the
University of California’s Cooperative Extension. “They are usually
overwatered. I think we ought to focus more on people’s watering behavior, and
less on replacing plants.”
Commercial turf grower Jurgen Gramckow
of Oxnard maintains many new drought-resistant landscapes won’t hold up when
rains finally come. “Landscapes with bark as ground cover, for example, will
lose a lot of it and clog storm drains, too,” he says. “The water agency
perspective on lawn replacement is one-dimensional. No one talks about
tradeoffs, negative effects.”
He’s right about that, which means
today’s lawn replacement fad may really be less about water savings than trying
to change attitudes, also known as social engineering.
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Email
Thomas Elias at tdelias@aol.com. His book, "The Burzynski Breakthrough,
The Most Promising Cancer Treatment and the Government’s Campaign to Squelch
It," is now available in a soft cover fourth edition. For more Elias
columns, visit www.californiafocus.net
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