At this point it’s just a parlor game, but has Lake Mead broken through the old “lowest since they filled it” record yet or not? Regardless of the fractions of an inch involved, it’s a big deal. (Go to Circle of Blue for an explanation.) But the conversation this week has been a bit confused about whether we’ve actually crossed this milestone or not.
Here’s how the Bureau of Reclamation put it in their official news release Tuesday:
BOULDER CITY, Nev. – Lake Mead, the reservoir created by Hoover Dam, is anticipated this week to reach its lowest water level since the lake’s initial filling in the 1930s. The Bureau of Reclamation’s Boulder Canyon Operations Office is projecting the elevation to drop to 1,081.75 feet above sea level during the week of July 7 and to continue to drop, reaching approximately 1,080 feet in November of this year.
The old “record” was set in 2010, when Lake Mead bottomed out at 1,081.85 feet above sea level in the 9 p.m. hour on Nov. 27 (source pdf):
On Tuesday, the same day as the press release went out, Mead briefly dropped below that point, to 1,081.84:
But it didn’t last, popping right back up. Hydrologists at the Bureau point out that the levels were bouncing around quite a bit, and there was a storm in the area, so maybe it’s questionable data? We’re talking tiny fractions of an inch here, which is why this is just a silly parlor game. On Wednesday, it briefly got as low as 1,081.82 before popping back up.
On Thursday it hovered above the old “record” all day (and it rained!). Today, it’s still above the old record.
I don’t claim to be a hydrologist or scientist for that matter. I do say that the wind will influence a lake level on the tailing edge (think North winds here blowing on the water and a box like canyon just above the dam). When the wind blows on a lake — it will influence the level. It can go up or down depending on the wind direction and intensity. No one really notices these things. I guess that you did. Good catch to see the difference in the hourly readings, John.
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