We’re inundated with words and pictures about Helene. I’ve tried to put Helene into perspective by using numbers (forgive me) to develop mental images. I’m not trivializing anything, nor ignoring the devastation and misery Helene has caused.
The first number I heard was forty trillion – Helene dropped 40 trillion gallons of water on the Southeast. I couldn’t believe it, but they persisted: 40,000,000,000,000 gallons of water. So I started with that. Obviously, if that number’s fraudulent, then my results are incorrect, too.
First, using Earth’s surface water for reference, 40 trillion gallons is only 1/64 of an inch off the top of all the oceans.
That doesn’t illustrate Helene.
Next: 40,000,000,000,000 gallons ... there are 7-1/2 gallons in a cubic foot and 5,280 feet in a mile. Forty trillion gallons is more than 36 cubic miles of water, enough to cover Hamilton County 330 feet deep, or all of Tennessee 4-1/2 feet deep – chest high.
I keep wondering ... is 40 trillion gallons really correct? News broadcasts aren’t always accurate, and those pretty people just read whatever’s handed to them.
Thirty-six cubic miles: Lookout Mountain is a quarter mile high and some miles wide. Follow it far enough into Georgia and you’ve got 36 cubic miles of rock. That’s a useful image – a tsunami the size of Lookout Mountain is devastating.
But Lookout Mountain isn’t water. Our opposite neighbor, Chickamauga Lake, is all water, and it’s big. Chickamauga Lake has about 57 square miles of water surface, up to 72 feet deep. How much water is that altogether? Apparently during summer, Chickamauga holds about 200 billion gallons of water. That’s a lot, but Helene’s 40 trillion gallons is two hundred times as much.
The folks east of us got the equivalent of 200 Chickamauga Lakes dropped on them.
Does that make sense? Do you feel like you understand now – that the big wind called Helene carried something like 200 Lake Chickamaugas worth of water, and dumped it all on our neighbors?
That’s inconceivable. To me, Helene was a few days of heavy overcast, hours of steady rain, and the usual sinus trouble. Even as an academic problem, Helene is incomprehensible. I keep thinking my numbers are wrong, but I can’t find an error. If that forty trillion gallons is incorrect, will we ever know?
But seeing videos of the aftermath – that’s convincing. The Ground Zero result is real enough for those who lost everything. Again, I’m not minimizing their plight; the kind of numbers they need most now have dollar signs – relief that is already too little and too late. Government promises and insurance policies are never quick to deliver, never simple, and those overwhelmed folks need help right there, right now.
My numbers do explain the awful floods of water we’ve seen running in rivers, across roads, and over rooftops. And consider all the mud, broken trees, ruined homes, wrecked vehicles, destroyed downtowns, pulverized roads and bridges ... I’m imagining all of that waste piled up as big as Missionary Ridge.
Numbers, pictures, whatever ... Helene is unfathomable. Second to Katrina? We’ll see ... .
Another humanitarian thought: Can you imagine paying property taxes on a home that just went down the river? Wait for it.
Larry Cloud
Chattanooga
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Or maybe use this formula in figuring out total gallons of water.
One inch of rain over one acre is 27,154 gallons.
Many places had 30 inches of rain.
So that would come to 814,620 gallons over one acre.
Just something to think about next time you get a lot of rain in a short period of time.
Ted Meyer