tolakram wrote:txwatcher91 wrote:tolakram wrote:Addicks looks to have stabilized for now at 108.85'
[i mg]http://i.imgur.com/ICxzhRO.png[/img]
Either that or the gauge is having issues. Hard to know for sure but hopefully it has stabilized and isn’t a gauge issue.
So far I have not seen anything about an error. When the other dam's sensor went out the readings stopped.
It is the sensors that have not even been discussed here that may be crucial. These (IF present) monitor the stability of the main spillway gates.
Previously I'd posted about the auxiliary spillway (emergency spillway) overtopping, where erosion over a long period of drainage, if necessary, could be an issue. But apparently there IS another issue: The main spillway is basically a big underground concrete pipe, and has suffered soil erosion around it. What were essentially patch job repairs were done in 2009. New gates to replace the old gates are under construction, but not yet completed.
See these links:
https://youtu.be/iwTjhjRPCeMhttps://youtu.be/yezfTeE7r_o (esp. 10:52 for a drawing of the structure -- the foundation is fine sand)
Depending on how much erosion has occurred, failure at the main gates is a possibility. Hopefully it is a very low possibility. In an extreme case, the head (water pressure) at the gates could literally eject the gate from the dam.
The Corps of Engineers considers these "high risk dams", but apparently more because of how critical they are, than an actual risk of failure.
https://www.texastribune.org/2017/08/29 ... oing-fail/