When Willis Carrier patented the air conditioner in 1906 he probably didn’t realize that he had just introduced a sea-change in urban-planning: would Miami, Phoenix or Las Vegas be what they are today without the ability to cool indoor air? The air conditioner was one simple innovation that radically- and rapidly- altered the options for human habitation.

An insight I gained from a presentation by the Southern Nevada Water Authority (SNWA) at the American Planning Association’s conference in Las Vegas was that, contrary to popular belief, the biggest water expenditure on the Vegas Strip is not the dancing fountains or faux Venetian canals. In fact The Strip’s principle users of non-recyclable water are the resorts’ vast air conditioning systems.   

 

More significant than that, the biggest overall water-consumer in Las Vegas isn’t on The Strip at all, but is rather found in the form of ornamental lawns used in residential and retail developments.

 

Las Vegas has flourished in a climate that one ordinarily couldn’t grow a tomato in. The city’s story is a tenacious example of urban development over the last century or so. Thanks to Mr. Carrier’s invention, the Chicago mafia and several dauntless developers, a rail stop in the Mojave Desert with a meager water apportionment from the Colorado River became a worldwide entertainment destination and home to a half- million people.

Nature though, is having her say:  During the last decade, 4.5 trillion gallons have been extracted but not replenished from Lake Mead- Las Vegas’ principle water source. In the end, water may what ultimately curtails Las Vegas’ remarkable growth.

   

Rapid suburban development brought thousands of new single-family homes and retail stores with green decorative lawns and few shade trees to an environment with less than four-and- a- half inches of rain per year, and average peak temperatures of 110 degrees. Currently, outdoor residential and retail uses consume about two-thirds of the city’s water. Ornamental turf draws 73 gallons-per- lawn-foot each year- a consumption rate that would require ten feet of yearly rainfall to sustain.

As a result, city planners are rapidly adapting water conservation measures that have been surprisingly simple and effective. By using “carrots and sticks” and an ambitious outreach program, the SNWA has converted 100 million square feet of decorative lawn turf into a water conserving uses, and has reduced overall water consumption from 350 gallons per capita per day to 260 gallons per capita per day.

A “carrot” that the water authority uses is a rebate in the amount of $1.50 per square foot of lawn that business and residential consumers replace with water-efficient landscaping; a “stick” has been the $400,000 in fines that they have collected from water restriction violators in just one year alone.

Lawn designs are now required to be both smaller and substantively covered by native plants that are well-suited to the dry climate. This design requirement has, according to SNWA, reduced the water demand from the aforementioned 73 gallons per lawn-foot per year, to just 17 gallons per lawn-foot/year.  

For larger public uses, vast swaths of decorative lawn areas have been converted from turf to desert landscaping with minimal-to-no water demands. In recent years 52 school lawns and twenty million square feet of golf course turf has been converted to desert landscaping. City public restrooms have been installing waterless urinals and new homes are being built with low-flow toilets and high water efficiency-rated plumbing fixtures.

Conservation alone is not the answer- the SNWA is getting ready to spend between $172 million to $206 million in order to build a new reservoir near the Mexican border - but conservation is a huge component of the water planning equation and, increasingly, it’s an indispensable one.   

 

Obviously, Napa Valley isn’t Las Vegas, but we can probably draw a few parallels. Although not situated in the middle of a vast desert, we do have a lush-agricultural preserve on the floor of a valley otherwise surrounded by dry hills. Between local reservoirs, wells, and our share of the state water project, the Valley has increasing demand and a finite number of replenish-able water sources.

 

Each new proposal necessarily runs a gauntlet of water considerations. I think of a recent commercial project before the American Canyon commission when we required the developer to lay down recycled water infrastructure -“purple pipe”-at the start of construction, rather than the unspecified time in the future that he was asking for. Although creating a steeper initial cost that the developer understandably hoped to avoid, the commitment to water conservation in our city planning is absolute, and is being enforced at all opportunities.  Drought resistant landscaping, storm water runoffs, and low-flow appliances have also now become staples in every project application that I have seen in the last three years.

 

We’re entering a new conservation mindset- the era of half-measures is over. While a debate can be had about the size of our population, incorporating conservation and sustainability at the nascent planning stages at least addresses the important reality that the conspicuous-consumption party is over. The conservationist argument has always been to use an ounce of prevention today to avoid a pound of cure tomorrow. Our window on being able to do that may be very close to closed however: high fuel prices and a new round of water-rationing across the nation this summer are the canaries in the coalmine for the non-sustainable growth mindset.