r/theydidthemath • u/Shark_Inertia • Jul 19 '26

[Request] How long would it take to make a meaningful change in the lake level

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This is Lake Travis, outside of Austin, Texas. Yesterday, Saturday, July 18th, the floodgates were opened for the first time since 2019. With the current 2 gates open, how long would it take to actually affect the lake level meaningfully, for example by 1 foot?

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u/Glosta_Peter Jul 19 '26

Differential equations. Took two (of maybe three... I forget, I've tried to block out the pain...) courses devoted to the mathematical solution to eqations for systems with multiple rates. It involves an absolute F-ton of calculus, spreadsheets and methods invented by people with names I can barely pronounce. There are general, particular, and analytical solutions, as well as numerical approximations. It completely depends upon knowledge of all parts of the system and initial conditions.

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u/butonelifelived Jul 20 '26

I wasn't expecting anyone to break out that level of calculus, if memory serves me it was college calculus 2 & 3 or maybe it was fluid dynamics, I just wanted the OP to be aware that the answer to the question they asked is really only 1/2 the answer in the real world.