The concern about this high pressure anomaly is that the
longer it lasts, the less likely it will be to break up soon, and in the
interim reinforces the jet stream’s current northern trajectory. While it’s quite possible that extremely rare
events like the Triple R are simply borne by chance (and so may end at any time),
given that higher global temperatures have raised the risk of rare weather
extremes, there’s a distinct possibility that this drought may continue for
some time to come.
However, there are some important differences between this
event and the last major drought to hit California in 1976-77, in which the
state’s reservoirs plummeted to 41 percent of average capacity (versus just over
50 percent as of late August 2014). On
the demand side, although the state’s population has doubled since the last
drought, per-capita water use has also dropped with the use of new water
management technologies.
It was actually the drought of 1987-92 which marked the
beginning of modern water-use practices, including more efficient use of water
for agricultural which made more growth in the cities possible. Moreover, the delivery of water in general
has greatly reduced waste due to evaporation or seepage, while reclaimed water
for outdoor use is becoming increasingly commonplace, especially for water-hungry
uses such as golf courses and freeway embankments.
Consequently, whereas municipalities might simply have
refused to grant new building permits in past droughts, today the approval process
for new projects has water availability as a key component. For new developments of 40 acres or more in
California, since 2002 the state has required a water supply assessment in
order to confirm that there will be adequate supplies of water – which can also
include new sources through conservation, recycling and transfers -- as long as these sources include
appropriate quality, quantity and reliability.
On the supply side, new homes are actually exponentially
more efficient than older ones, especially those with water-hogging plumbing
fixtures. According to a report
commissioned by the CBIA, an average three-bedroom home with four occupants built
today uses 29,000 fewer gallons of water than smaller homes built in 2005. Certainly one big reason for that is the “CalGreen”
code, which become law in 2011 and mandated a 20-percent reduction in water use
through relatively simple solutions such as low-flow toilets, shower heads and faucets.
One builder on the forefront of the water issue is Los
Angeles-based KBHome, which debuted their first “Double ZeroHome” at its Dawn
Creek community in the high desert city of Lancaster (average annual
rainfall: 7-8 inches) earlier this year.
So named due to its dual emphasis on
energy and water efficiency, the home has been engineered to recycle its own
drainwater and re-purpose it for its low-water landscaping.
According to the builder, the home can save up to 150,000
gallons of water each year compared to an older resale home, for a savings of
about 70 percent. Other clever innovations include a dishwater that stores the
water from the last rinse cycle for use in the first pre-rinse cycle of the
next load, and an energy recovery system which extracts heat from drainwater
and diverts it to the home’s tankless water heater to cut down on heating
costs.
Still, based on sheer numbers alone, the solution to the
future availability of water has much more to do with retrofitting the existing
housing stock versus the approval of new homes; if homes 30 years of age or
older were retrofitted to the CalGreen standards, estimates of water savings statewide
rise to 300 billion gallons per year.
Yet with a housing inventory of over 13 million California residences, encouraging
homeowners to make these changes will be neither easy nor fast. Most likely, what we’ll see are a mix of
carrots and sticks from cities and water agencies to encourage greater water
efficiency in homes and businesses.
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