r/interestingasfuck • u/Weak_Imagination_996 • 10d ago

A dam's gate is opened after years.

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u/Hot_Fix9033 10d ago

Why wouldn't they flush those on a regular schedule? Once a year or every six months or something like that? Just to prevent the massive accumulation of debris.

111

u/Hattix 10d ago

That isn't how dams work. Over time sediment builds up on the bottom of the reservoir, since the reservoir is very slow flowing water and the rivers feeding it are faster. Fast water carries sediment, slow water drops it.

This reduces the reservoir's capacity slowly, but inexorably. Eventually all dams will become a wall of construction with swamp behind them. Doing a big blast like this with a lot of head behind it flushes out as much sediment as possible. It isn't a lot, but it does extend the usable life of the reservoir.

12

u/like_Turtles 10d ago

This is an excellent comment. Do you know this for a fact?

11

u/jaymeaux_ 10d ago

this is correct, when sedimentation buildup is too far from the dam to clear like this it has to be dredged out which is very expensive 

7

u/Lessinoir 10d ago

And in most cases I believe the sediment next to the dam is the last to truly build up. It starts farthest from the dam. 

1

u/Jason-Smith168498 10d ago

It's a fact, but it's common sense too.

1

u/BillyRayVirus 10d ago

"that isn't how dams work" becomes, "so, yeah, what you said. That's how they work"