Whaley Bridge evacuated as dam starts to crumble after heavy rain 1

[epoxybot]

https://metro.co.uk/2019/08/01/whal...-reservoir-suffers-partial-collapse-10501212/

 

[LittleInch]

More decent information here:

https://www.newcivilengineer.com/latest/engineers-battle-night-save-derbyshire-dam-02-08-2019/

Basically it's 180 years old, built mainly of earth and possibly some clay. Built to feed the peak forest canal which is still in operation as a leisure canal and apparently now also a wildlife refuge.

They are basically draining it as fast as they can via the normal feed into the canal.

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

 

[JohnRBaker]

Our old friend, of Oroville Dam fame, Juan Browne, has a video on the Whaley Bridge dam and spillway issues:

https://www.youtube.com/watch?v=Zm_MMRA9Szk

John R. Baker, P.E. (ret)
EX-Product 'Evangelist'
Irvine, CA
Siemens PLM:
UG/NX Museum:

The secret of life is not finding someone to live with
It's finding someone you can't live without

 

[SomptingGuy]

Thanks John. Nice to hear a reasoned engineering description of the situation (even if his mispronunciation of "Derbyshire" almost made me stop watching ).

The news over here is just overreaction. Nobody has attempted to explain how it's supposed to work and what appears to have gone wrong. Many viewer questions along the lines of: "Why can't they just pour quick-setting concrete into the hole?".

Steve

 

[itsmoked]

I take it water was spewing from the hole pictured above and they've amazingly gotten the level down below the hole now?

Keith Cress
kcress -

http://www.flaminsystems.com

 

[human909]

I take it water was spewing from the hole pictured above and they've amazingly gotten the level down below the hole now?

As far as I can tell no. If water starts spewing from a dam hole then it is usually all over, especially if it is an earthen damn.

This isn't too different Oroville damn spillway failure.

https://www.eng-tips.com/viewthread.cfm?qid=420883

To summerise:
Water was flowing down the spillway as designed but due to poor design/maintenance the concrete spillway failed enabling significant erosion on the back side of the dam. If such a scenario continues damn collapse is almost inevitable.

(I typed all the above quickly. So if anybody spots any mistakes I've made then please forgive me and correct me.)

This posted above explains it better:

https://www.youtube.com/watch?v=Zm_MMRA9Szk

 

[itsmoked]

dam[!]n[/!] hole then it is usually all over

That's what I was thinking but if that was a spillway that explains the possibility of avoiding a catastrophe.

Thanks for clarifying that.

Keith Cress
kcress -

http://www.flaminsystems.com

 

[EireChch]

The Army are currently sand bagging the dam and pumping out water to lower the head of water. Seems like all they can do for now in the short term. I image and remediation work cant happen until the dam is lowered below the level of the failure.

 

[Alistair_Heaton]

https://www.metoffice.gov.uk/weather/warnings-and-advice/uk-warnings#?date=2019-08-04

Weather warnings for today.

Getting the level down is going to be an issue.

 

[SomptingGuy]

BBC news this morning is claiming that the evacuated communities are "Protected by the dam". An odd way of looking at it.

[edited for clarity]

I'd say theat the dam is like a poorly maintained, loaded gun that the community have been living with for nearly 200 years.

Steve

 

[Alistair_Heaton]

Not if your on a help in the community job placement which seems to be a feature with a lot of the reporting these days.