Another Crisis - Shrinking Lake Mead

From the NPS Website

You’ve probably heard about Lake Mead and the fact that it’s shrinking, but if you’re not living in the area, it probably doesn’t have much impact on you other than perhaps a ‘Wow!” comment. Hurricanes in the southeast, blizzards in the northeast, tornadoes in the midwest, drought, earthquakes, mudslides, flooding… we hear about natural disasters every day, but when they’re not in your own backyard, you tend to feel for the folks involved and maybe you’re inclined to contribute some aid to the cause, but it’s not the same if it’s happening right here, right now in your own backyard and specifically to you. Our area is experiencing a massive drought, its driest period in 1,200 years.

All those white areas were once covered with water. Not any more! (NPS website)

A little history… In 1936, the largest reservoir in the USA was created with the completion of the Hoover Dam. When the lake began to fill, its level was ~708’ and submerged the tiny community of St. Thomas. The last citizen of St. Thomas rowed away from his home in 1938. According to the National Park Service (NPS), at one time, “the town was flooded higher than 60 feet above the tallest structure, now visitors can roam the ghost remains of a true western town.”

Remnants of foundations of the St. Thomas community once covered by Lake Mead’s water can now be explored. (NPS Website)

St. Thomas was uncovered by the drought… leading to many other discoveries in the lake” including at least five sets of human remains in recent months.” I found an NPS visual field guide to St. Thomas and it might be an interesting day trip someday soon.

Some tongue-in-cheek local advertising

Back to the current challenge… According to US News, “Over-extraction, extreme heat and decreased snowmelt have burdened the Colorado River Basin and... Lake Mead is down to about 27% of its capacity.”

Southern Nevada gets nearly 90 percent of its water from the Colorado River and Lake Mead is the principal source of water for the Las Vegas Valley. It’s a real concern for us. We already have water restrictions in place and there’s a restriction on planting new grass with generous rebates for removing existing lawns and replacing with artificial turf or a xeriscape area. New swimming pools cannot exceed 600 sq feet and pool covers to prevent evaporation are highly encouraged.

Not only do we depend upon Lake Mead for our drinking and agricultural water, southern Nevada and several other states depend on the Hoover Dam for electricity. If the water level sinks too low, the hydroelectric plant will be forced to shut down and will no longer be able to generate power. This is called deadpool, the level at which the water in a reservoir can no longer flow downstream from a dam. For Lake Mead, this level is 895 feet. Lake levels, by the way, are expressed as altitudes — the number of feet the lake’s surface is above sea level — not as depths.

Lake Mead is supplied almost entirely by snowmelt from the Rocky Mountains feeding into the Colorado River watershed through Lake Powell, Glen Canyon, and the Grand Canyon. Only about 10% of the water in Lake Mead comes from local precipitation and groundwater each year. Good thing because we don’t have too many rainy days here. NASA observatory officials said the lake holds 9.3 trillion gallons of water at an elevation of 1,220 feet when it is at maximum capacity which it last reached in 1983. By July 2024, Lake Mead is projected to reach 1013 feet.

The Colorado River supplies water to seven states, tribal nations and Mexico. California has the largest claim to the water, but they also use the most and have not yet committed to a reduction plan agreed upon recently by Colorado, New Mexico, Utah, Wyoming, Nevada and Arizona.

So why do all these areas have to share the water? The Colorado River Compact answers that question. Established in 1922 and ratified in 1944, the agreement between seven states located in the Colorado River Basin, was negotiated between the states and the federal government. My research didn’t mention any agreement participation by the tribal nations or Mexico. Were they left out of the discussions? Yes, they were. It was never imagined that the population of 457,000 which the Colorado River Basin served in 1915 would have to serve the 40 million it serves today.

So what is Nevada doing about it thus far? According to Lasvegasnevada.gov,
“On Aug. 16, 2022, the federal government declared a tier two water reduction on the Colorado River. This limited the amount of water Southern Nevada would be allowed to withdraw from Lake Mead beginning in January 2023. This came one year after the federal government, prompted by the low water levels in Lake Mead, issued a water shortage declaration on the Colorado River.

In January 2022, Southern Nevada’s water allocation was reduced by 7 billion gallons. Starting in January 2023, the allocation was reduced by an additional 1.1 billion gallons for a total of 8.1 billion gallons. Our 2023 allocation is 275,000 acre-feet of water, 4,000 acre-feet less than our 2022 allocation of 279,000.”

Fortunately, southern Nevada has been somewhat successful in its conservation efforts and used less than its allotment in 2021 and 2022. “Southern Nevada’s commitment to conservation has resulted in a 48 percent decline in per person water use per day since 2002, despite the addition of more than 750,000 new residents.”

So who uses the most water in Las Vegas? It ain’t the residents. The most recent data collected from 2021 shows golf courses used the most water in Las Vegas. In 2021, that changed (due to the pandemic) with casino properties taking over the top spots. Southern Nevada now limits golf courses in their water consumption with heavy fines if they overuse and new courses are not allowed to use Colorado River water. Not sure exactly what restrictions are put on casinos. Think about those fountains outside the Bellagio. The 1000+ fountains are contained in an 8.5-acre lake which holds more than 22 million gallons of water. This man-made lake loses an estimated 12 million gallons of water per year due to evaporation. Yikes! That’s a lot of potential drinking water!

Above average snowpack in the Rockies this year will definitely help the situation, but it’s only a drop in the proverbial bucket. It will take six consecutive above average wet years with limited extraction to make a significant impact. Hydrologists, climatologists and meteorologists are not optimistic that this will happen.

On the positive side, Lake Mead has been slowly rising. Now at 1,047 feet as of this writing, it is about 6 feet above where it was near the end of July 2022 (1,041 feet). On the downside, that’s about 21 feet below where it was a year ago today. Sigh!

I’m not giving up hope, but I think we’ll have to figure this out soon or get mighty thirsty.