Slash Boxes

SoylentNews is people

posted by janrinok on Thursday June 10 2021, @08:04PM   Printer-friendly
from the get-off-my-lawn! dept.

Las Vegas's new strategy for tackling drought – banning 'useless grass':

A new Nevada law will outlaw about 40% of the grass in the Las Vegas area in an effort to conserve water amid a drought that is drying up the region's primary water source: the Colorado River.

Other cities and states around the US have enacted temporary bans on lawns that must be watered, but legislation signed Friday by the state's governor, Steve Sisolak, makes Nevada the first in the nation to enact a permanent ban on certain categories of grass. Sisolak said last week that anyone flying into Las Vegas viewing the "bathtub rings" that delineate how high Lake Mead's water levels used to be can see that conservation is needed.

"It's incumbent upon us for the next generation to be more conscious of conservation and our natural resources, water being particularly important," he said.

The ban targets what the Southern Nevada Water Authority calls "non-functional turf". It applies to grass that virtually no one uses at office parks, street medians and the entrances to housing developments. It excludes single-family homes, parks and golf courses.

The measure will require the replacement of about 8 sq miles (21 sq km) of grass in the metro Las Vegas area. By ripping it out, water officials estimate the region can reduce annual water consumption by 15% and save about 14 gallons (53 liters) per person a day in a region with a population of about 2.3 million.

If you want grass, go live where grass grows naturally.

Original Submission

This discussion has been archived. No new comments can be posted.
Display Options Threshold/Breakthrough Mark All as Read Mark All as Unread
The Fine Print: The following comments are owned by whoever posted them. We are not responsible for them in any way.
  • (Score: 5, Informative) by Runaway1956 on Thursday June 10 2021, @09:57PM (4 children)

    by Runaway1956 (2926) Subscriber Badge on Thursday June 10 2021, @09:57PM (#1144093) Homepage Journal

    Trees may or may not need less water than a lawn - but they still need a lot of water. []

    Different trees have different water requirements, but as a general rule, most trees need about 10 gallons of water every week or two, for every inch of tree diameter at breast height (about 4.5 feet above the ground). In other words, a walnut tree with a 6-inch-diameter trunk will require about 60 gallons of water every other week.

    Note that running 60 gallons of water onto arid ground isn't going to provide 60 gallons of water to the tree in question. Evaporation and leaching is going to lose a lot of water, even if you're careful to avoid runoff. []

    Plant transpiration is pretty much an invisible process. Since the water is evaporating from the leaf surfaces, you don't just go out and see the leaves "breathing". Just because you can't see the water doesn't mean it is not being put into the air, though. One way to visualize transpiration is to put a plastic bag around some plant leaves. As this picture shows, transpired water will condense on the inside of the bag. During a growing season, a leaf will transpire many times more water than its own weight. An acre of corn gives off about 3,000-4,000 gallons (11,400-15,100 liters) of water each day, and a large oak tree can transpire 40,000 gallons (151,000 liters) per year.

    40,000 gallons of water per year, in a region that only gets about an inch of rain per year. That doesn't really look sustainable.

    Your private safe room in the back of your mind? Trump pooped in it.
    Starting Score:    1  point
    Moderation   +3  
       Insightful=1, Informative=2, Total=3
    Extra 'Informative' Modifier   0  
    Karma-Bonus Modifier   +1  

    Total Score:   5  
  • (Score: 1, Insightful) by Anonymous Coward on Friday June 11 2021, @02:47AM

    by Anonymous Coward on Friday June 11 2021, @02:47AM (#1144157)

    Yep, that's why native plants are usually preferable. You don't have to water them much once they're established. In this case, probably a bunch of succulents and whatever trees have adapted to live with such little rain.

  • (Score: 5, Informative) by Reziac on Friday June 11 2021, @02:54AM (2 children)

    by Reziac (2489) on Friday June 11 2021, @02:54AM (#1144158) Homepage

    There are a lot of desert-adapted trees, as well as desert-adapted grass (sheep fescue does well, and makes a nice lawn that doesn't need mowing). And one way to prevent needless evaporation is to shade the soil... with trees.

    And the way to reduce plant transpiration is to... increase CO2, because that is WHY those spiracles are open so much -- trying to suck up enough CO2 to avoid starvation. Which has the unfortunate side effect that more H2O escapes. (See also NASA's images showing that Earth has been generally greening, and guess why.)

    Native desert juniper forest (this is land that has never been cleared, and has survived many years of drought): []
    Various more-conventional shade trees also do well, once started. Notably Italian stone pines will survive where nothing else does, in areas that may measure annual rainfall in fractions of an inch. Here's a volunteer stone pine (note the dead juniper to the left, which died about 15 years ago): []
    Turn around and look south, and you'll see some Turkish pines that were planted in the 1930s (not irrigated in living memory).
    Since I'm in the neighborhood: Honey locust. To the west, the windbreak is saltcedar (I used to live next to 'em). To the north, Siberian elms that L.A. County failed to kill with their tree topping program: []
    None of these get anything but the scant rainfall.

    Now, take a look at the satellite view of Las Vegas. Private lawns are small and usually already bordering on brown. The primary offenders for "needless grass" are golf courses and the outdoor sports complex. Want to bet whether they'll be required to let their grass brown out?

    • (Score: 5, Informative) by srobert on Friday June 11 2021, @03:21AM (1 child)

      by srobert (4803) on Friday June 11 2021, @03:21AM (#1144166)

      The golf courses in Vegas have already removed a lot of unnecessary grass in recent years. Compare satellite photos of Vegas golf courses 20 years ago and now. And much of the Las Vegas golf course irrigation is achieved using recycled water. That's water extracted from the sewer system that has been treated for non-potable purposes. If you ever see the water company installing purple pipes that's what they're for.

      • (Score: 2) by Reziac on Friday June 11 2021, @03:31AM

        by Reziac (2489) on Friday June 11 2021, @03:31AM (#1144169) Homepage

        Good to know. Frankly that's water that would otherwise be wasted, so why not put it on something green and growing?