Lake Delton, Wisconsin- 90% drained
#1 Guest_NVCichlids_*
Posted 09 June 2008 - 07:07 PM
here is the story so far:
http://www.todaystmj...l/19656854.html
what will happen to the fish that are still stuck in what is left and how will the ecosystem change in the Wisconsin River change??
NV
#2 Guest_ashtonmj_*
Posted 09 June 2008 - 07:32 PM
#4 Guest_ashtonmj_*
Posted 09 June 2008 - 08:30 PM
will the lake ever be the same?
If you mean a man made impoundment again then probably not. My understanding is the water cut a channel around the dam and caused a near entire breach. Getting a permit for a large recreational impoundment is about next to impossible. The earthen dam was probably old or insufficient for such a flood and how would such high project costs be justified to remake it, especially if it is not multipurpose.
The debris from 5 houses is miniscule compared to the total amount of debris going into the Wisconsin River.
#6 Guest_NateTessler13_*
Posted 10 June 2008 - 07:50 AM
http://www.jsonline....p;photoid=23086
#8 Guest_nativeplanter_*
Posted 10 June 2008 - 09:51 AM
If you mean a man made impoundment again then probably not. My understanding is the water cut a channel around the dam and caused a near entire breach. Getting a permit for a large recreational impoundment is about next to impossible. The earthen dam was probably old or insufficient for such a flood and how would such high project costs be justified to remake it, especially if it is not multipurpose.
The debris from 5 houses is miniscule compared to the total amount of debris going into the Wisconsin River.
Looking at the photos, I bet it will be rebuilt. There are a lot of commercial interests at stake. Getting a permit for a recreational impoundment is tough, but the permit would not be for a new impoundment, only dam repair. Different thing entirely.
I can't imagine it will cause any major, long-term changes to the ecosystem of the Wisconsin River. The drainage area and overall contribution to the river made by Lake Delton is not that substantial. There likely was a large influx of sediment but is likely being scoured and washed away down the river with the flooding discharge.
Is sediment really not that much of a problem? Whenever we talk dam removal, the first question is "what are you going to do with the sediment"? Maybe it's because during planned removals, there isn't a flood going on to scour downstream?
#9 Guest_edbihary_*
Posted 10 June 2008 - 10:34 AM
Exactly. A deliberate dam breach will be done in a controlled way to avoid flooding downstream areas. Such a controlled discharge should not be capable of carrying a tremendous amount of suspended sediment. On the other hand, a catastrophic dam breach like Lake Delton will have a high flow rate and velocity which is capable of carrying much suspended sediment. Regardless, I would expect there to be some short term impacts like during any flooding event. And that sediment is going to end up somewhere. I have no idea what's downstream of that dam breach, but I imagine that some river and/or downstream impoundment will end up at least partially choked with that sediment. Eventually the floodwaters will dissipate (spread out and slow down) and drop the sediments somewhere.Is sediment really not that much of a problem? Whenever we talk dam removal, the first question is "what are you going to do with the sediment"? Maybe it's because during planned removals, there isn't a flood going on to scour downstream?
#10 Guest_nativeplanter_*
Posted 10 June 2008 - 10:56 AM
#11 Guest_edbihary_*
Posted 10 June 2008 - 11:04 AM
Very true. Therefore, (at least here in Pennsylvania, and I assume most other states,) a permit must be obtained to remove a dam. An erosion and sediment control plan must be submitted as part of the permit application, and implemented during dam removal, to trap sediments before they enter streams. Of course, that is just one of many good reasons that a permit is required to remove a dam.Actually, a controlled dam removal will result in a large amount of sediment movement. It's just that the downstream flow won't be as high as during a flood. The sediment will remain closer to the dam site, but will most certainly become mobile and move below the dam, with potentially very negative effects to habitat.
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