There is only a 16 foot difference from the crest of the capillary and the top of the rotary gates which marks the max surface level of lake mead. The bathtub ring is 140 feet tall it is caused by the chemical action of water on the sand stone when submerged once the water levels drop the now dry sand stone shows where the water has leached minerals out of the stone causing a bleaching effect. Lake mead is at 1067 feet as of today a historical low. At 950’ the last 5 turbines don’t have enough water pressure to make power anymore. At 895’ lake mead cannot pass water down stream and enters deadpool. Las Vegas just drilled 3 miles under the lake to put in a third intake pipe at 860’ that’s 35 feet below dead pool and would allow Vegas to take water to nearly the bottom which due to sedimentation is at 725’ up nearly 200 feet since Hoover dam went it.
Lake mead is full at 1221’ this is 16 feet above the crest of the spillway sill at 1205’ the drum.gates make up the difference.
https://www.nps.gov/lake/learn/nature/storage-capacity-of-lake-mead.htm
Lake Mead Water Level Timeline
The water levels at Lake Mead have visibly fluctuated over the years. Despite the fluctuations, the lake is still one of the largest reservoir in the United States with depths surpassing 300 feet. It is the sixth most visited unit of the National Park System and the premier inland water recreation area in the west.
February 1935 Lake begins to fill to 708.70 feet
July 1941 Lake Mead reaches 1220.40 feet
March 1956 Lake Mead drops to 1083.57 feet
July 1983 Lake Mead reaches 1225.44 feet (highest point)
June 2015 Lake Mead reaches 1074.71 feet
May 2022 Projected to be 1059 feet
They have allowed to many people into Las Vegas.
Plain and simple.