I thought the “ring” was there from the start when they let the reservoir level go to the max to initially test the overflow channels.
C'mon now, don't let facts get in the way of a good cackle.
After the Deluge (a proven event) that bathtub ring was in a totally different spot. Remind her of that.
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