LAS VEGAS (KLAS) — From July 13, 2021, to July 13, 2022, Lake Mead’s water level has dropped a little more than 26 feet. It’s a massive amount of lake-level movement, but not as much as what was seen at the lake between 1951 to 1964.

But first, some perspective. The reasons for the dramatic water loss and gains in these years compared to this past year are vastly different. Officially this past year’s water loss is mainly due to the 20-year drought in the west and a much thinner snow pack and snow melt in the Rockies. But 50 to 70 years ago Lake Mead’s water levels were changing in part due to new dams being built to the south and north.

After the Hoover Dam was completed in 1935 the Bureau of Reclamation opened two major dams to the south, the Imperial Dam and Parker Dam both in 1938. The Davis Dam, the closest dam to date to Lake Mead, went online in 1951.

The 1950s

Saint Thomas on the Muddy River, the upper arm of Lake Mead, shows the appearance of old Main Street after the lake had gone down, on April 18, 1951. Lake Mead is in the background. (Photo: UNLV Digital Collections)

Beginning in early 1951 the level of Lake Mead had fallen about 10 feet from the year before. This drop revealed something that had been mostly underwater since the initial filling of the reservoir. The small Mormon town of St. Thomas had resurfaced from deep under the Overton arm of Lake Mead.

When the Davis Dam opened in 1951 on what would become the north end of Laughlin, not only did Lake Mohave begin to fill, but Lake Mead’s water level also rose just over 30 feet in one year.

That large increase was short-lived as the lake fell 40 feet in one year between 1953 and 1954.

Just one year later between 1956 to 1957 Lake Mead actually rose more than 62 feet. Over the next three to four years the lake’s water level would go up and down about 10 to 20 feet a year.

Lake Mead water level between 1951 – 1966. (Data: U.S. Bureau of Reclamation)

The 1960s

Then between 1961 to 1962, Lake Mead had a large growth spurt rising another 46 feet in one year to 1,200 feet above sea level. This is 158 feet higher than today’s level.

But after a year, the lake level would once again fall dramatically. From 1963 to 1964 Lake Mead would drop 57 feet, more than twice the height of the 2021-2022 lake level drop.

These huge lake level changes were brought under control beginning in 1966 with the opening of the Glen Canyon Dam to the north. This is the dam that created Lake Powell.

The 1970s to Today

Once the Glen Canyon Dam was opened the water flow downriver could be better controlled. This can be seen in the relatively steady levels seen at Lake Mead over the next 15 years. The increased flow of water coming from a heavy snowpack in the Rockies led to Lake Mead reaching a ‘full pool’ in the summer of 1983.

Lake Mead water level between 1970 – 2022. (Data: U.S. Bureau of Reclamation)

Since the ‘full pool’ days of 1983, Lake Mead dropped over the next 7 years before rising again to almost ‘full pool’ in the late 1990s. After this, the water level of Lake Mead dropped most years except for a noticeable increase in 2012.

Dead Pool

As of July 13, 2022, Lake Mead is at 1,041 feet above sea level. If the lake were to fall below 895 feet it would no longer be able to produce electricity at the Hoover Dam, rendering the lake at dead pool level. This means reservoir water levels are too low to reach the lowest water outlet at Hoover Dam and flow downstream.

8 News Now asked the Bureau of Reclamation if there are plans in place to continue the flow of water downriver, around, through, or over the dam if the lake reaches dead pool. “We are working closely with river stakeholders to prevent Lake Mead and Lake Powell from declining to these depleted levels,” Bureau of Reclamation Public Relations Specialist Doug Hendrix told 8 News Now.

“At present, Reclamation is working with major water districts and representatives of the seven Basin States to conserve between 2 and 4 million acre-feet of water in the next few years to avoid the potential of the reservoir dropping to this level,” Hendrix added. “Senior leadership from the Interior Department are currently negotiating with all Colorado River stakeholders to determine where this water will be conserved.”