Much of the Western United States has been in the throes of a serious drought that has been carrying on for nearly six years. Las Vegas, Nevada, resides in the middle of the desert, and gets most of its water from Lake Mead and the Colorado River. But Lake Mead’s water supply is shared with other surrounding areas primarily to the south and west, and has dropped to record low levels. Each member water district has a predefined limit to the amount of water that it can withdraw from Lake Mead. The population of Las Vegas has grown from about 165,000 in 1980 to nearly 650,000 in 2021. The entire Las Vegas Valley’s population is currently about 2.2 million. But the amount of water this large desert community gets from Mother Nature has been steadily declining in recent years. What are the area’s water authorities doing about it?
Increase Water Recycling: According to the Las Vegas Valley Water District, virtually all water used in households and businesses is recycled. The process of recycling usually includes reverse osmosis, a filtration process that uses a membrane that filters out particulate matter, and a variety of contaminants from the water. Most organic substances like oils, bacteria, viruses, metals, and others are removed. Further, up to 99% of radionuclides, radium and uranium are filtered out along with harmful contaminants such as arsenic and nitrate. Water that completes recycling is then returned to Lake Mead. Every ton of water that is returned to the lake results in a ton of water that the Water District may withdraw from the lake without impacting predetermined and Federally enforced limits.
Restricting Water Features Along the Strip: The Las Vegas Strip features many large casinos and hotels that generate most of the area’s economy. Some of these hotels have water features such as fountains that react to music, or boat rides in and around the hotel’s shopping areas. Most of these water features consume no more than about 5% of the area’s total water supply. In some cases, privately owned water is used that does not impact the area’s Colorado River allocation from Lake Mead. Although no actions have been taken yet to limit water consumption in these places, the Southern Nevada Water Authority has contemplated bans or restrictions that would protect against, among other things, losses of water due to evaporation.
Blocking Construction of Large Private Swimming Pools: A number of private homes in the Las Vegas area have been built in recent times with ultra large swimming pools and spas. Some of these pools are larger than 3000 square feet, or 100 feet long by 30 feet wide. And the irony of some of these oversized pools is that they are in use only a portion of the year. New building codes will limit pool size to 600 square feet, or closer to the current average size pool of 470 square feet. The concept was not about restricting actual swimming recreation, but more towards blocking large aquatic facilities built primarily for show purposes in residential properties. The payoff comes in reduced water lost to evaporation.
Removing grassy lawns: Grass that grows in a homeowner’s lawn or in front of commercial buildings is deemed “non-functional” and has been a major focus of the Water District’s conservation efforts. Grass and spray-irrigation systems have been banned from all new properties except for schools, parks, and cemeteries. Single family homes since 2003 have been prohibited from growing grass in their front yards and restricted as to how much may be planted in side and backyards. Approximately 200 million square feet of non-functional grass has been removed from the area, but perhaps that same amount still remains. In 2021, the state legislature banned the use of Colorado River water to irrigate non-functional grass. The Water District estimates that this ban would save as much as ten percent of the area’s annual overall water supply.
Punishing Water Rules Violators: The Southern Nevada Water Authority has tightened its strict limits on outdoor watering to three assigned days per week for fall and spring months and one day per week during the winter. In the summer this increases to six days per week, but only at night or in the morning before 11AM. Fines begin at $80 per occasion, but are doubled with each subsequent occurrence. Since the watering rules have placed virtually all users on the same schedule, it becomes easier for the Water Authority’s enforcement unit to spot and cite violators.
Conclusions: Las Vegas is placing its chips on water conservation as opposed to waiting and hoping for Mother Nature to relieve the drought conditions. Like many reservoirs in the West, the water from Lake Mead must be shared to the point of rationing under certain circumstances. But understanding these problems and establishing the framework to work through them should enable the Las Vegas Valley to continue to thrive during this long drought.
Sources: Las Vegas Isn’t Betting on Mother Nature to Solve its Water Problems, by Stephanie Elam, CNN. September 5, 2022.
What is Reverse Osmosis Water Filtration? By Bridget Edwards, synergyscience.com. June 16, 2022.
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