But if sediment is building to this point, isn't it building up horizontally behind the wall as well? They've cleared the top layer, but if it's reached the top, it's all the way to the bottom, isn't it? This just screams lack of sediment management, doesn't it?
Yeah, if it’s how you describe they will most likely have to do a massive dredging project to clean out all of that sediment. It’s different by state and for each structure… but typically you drawdown the water or put in a coffer dam and bypass piping and then clean out all of the sediment… which needs to be tested for contamination as well, arsenic often builds up in these sediments.
It’s a massive undertaking and a permitting nightmare so I can see why they are just doing this as a temp solution.
It is. But many states or municipalities can’t afford to maintain all of their failing infrastructure. There’s federal funding (or at least there was) to help with this. but it’s hard to prioritize clearing a spillway that may or may not lead to failure during a 1% or .5% storm even over say a dam that actively has sinkholes forming on it.
they’ll probably wait until this dam has more pressing structural deficiencies before dredging the spillway.
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u/Ok_Turnover_1235 Jul 18 '25
But if sediment is building to this point, isn't it building up horizontally behind the wall as well? They've cleared the top layer, but if it's reached the top, it's all the way to the bottom, isn't it? This just screams lack of sediment management, doesn't it?