The biggest concerns right now in the United States are Lake Powell, behind Glen Canyon Dam on the Utah-Arizona border, and Lake Mead, behind Hoover Dam on the Nevada-Arizona border. The U.S. Bureau of Reclamation recently revealed unmatched changes in its guideline of the water in Lake Mead and Lake Powell. The bureau will maintain in Lake Powell 480,000 acre-feet of water that was arranged to flow down the Colorado River through the Grand Canyon and into Lake Mead for usage by California, Nevada, and Arizona. The water level in Lake Powell was 3,522 feet on April 30, 2022– just 32 feet above the minimum power swimming pool elevation of 3,490 feet. As levels in the lakes decline, each foot of elevation holds less water.
As a 22-year dry spell in the Colorado River basin sticks around, reaching minimum power pool elevation is the first issue. Lakes Powell and Mead have turbines at the bases of their dams, well below the surface area of the reservoirs. Water streams through valves in consumption towers in the reservoirs and is directed through the turbines, making them spin to create electrical energy.
Water levels in the Colorado Rivers significant reservoirs are falling to levels not seen considering that the reservoirs were produced.
This system relies on what hydrologists call hydraulic head– the amount of liquid pressure above a provided point. The greater the level of water above the turbines in Lake Powell and Lake Mead, the more hydraulic head they have and the more power they will produce.
When the level in a tank approaches minimum power pool elevation, the turbines lose capacity to produce power as they start to take in air together with water and must be shut down prior to they are damaged. A reservoir that reaches this point typically has rather a bit of water left prior to it drops to dead swimming pool and water stops flowing from the dam.
The U.S. Bureau of Reclamation recently announced unprecedented changes in its guideline of the water in Lake Mead and Lake Powell. The bureau will keep in Lake Powell 480,000 acre-feet of water that was scheduled to stream down the Colorado River through the Grand Canyon and into Lake Mead for usage by California, Nevada, and Arizona. One acre-foot is about 325,000 gallons.
Water from Flaming Gorge streams into the Green River and eventually into Lake Powell. The water level in Lake Powell was 3,522 feet on April 30, 2022– simply 32 feet above the minimum power swimming pool elevation of 3,490 feet.
Crucial points for Lake Powell and Lake Mead
These reservoirs, the two biggest in the U.S., are at the most affordable points given that they were filled in 1934 (Lake Mead) and 1963 (Lake Powell).
The white bath tub ring around Lake Mead is roughly 160 feet high presently and shows falling water levels.
Reporters reporting on the status and future of the Colorado River are progressively utilizing the expression “dead pool.” It sounds threatening. And it is.
When water in a tank drops so low that it cant stream downstream from the dam, dead swimming pool occurs. The most significant concerns today in the United States are Lake Powell, behind Glen Canyon Dam on the Utah-Arizona border, and Lake Mead, behind Hoover Dam on the Nevada-Arizona border. These two reservoirs, the largest in the U.S., supply water for drinking and watering and hydroelectricity to countless people in Nevada, Arizona, and California.
Some media reports have actually incorrectly specified dead pool as the point at which a dam no longer has sufficient water to produce hydroelectricity. The more precise term for that situation is the minimum power swimming pool elevation.
Table: The Conversation, CC BY-ND Source: U.S. Bureau of Reclamation
The bureau acted unexpectedly since the levels in both lakes have dropped far faster than anyone forecast. In the last year, Lake Mead dropped 22 feet; Lake Powell, 40 feet.
Severe dry spell and environment modification partially describe this fast decline. Another aspect is that Glen and Boulder Canyons are V-shaped, like martini glasses– wide at the rim and narrow at the bottom. As levels in the lakes decline, each foot of elevation holds less water.
In the meantime, finding sufficient water to keep producing electricity is the focus. Unless California, Nevada, and Arizona make big cuts in the amount of water they utilize, dead swimming pool in Lake Powell and Lake Mead cant be ruled out.
Composed by Robert Glennon, Regents Professor and Morris K. Udall Professor of Law & & Public Policy, University of Arizona.
This article was first published in The Conversation.
Lake Mead
1,054.69 feet
1,000 feet
895 feet
Reservoir
Water level on April 30, 2022
Minimum power pool elevation
Dead swimming pool elevation
Lake Powell
3,522.77 feet
3,490 feet
3,370 feet