Whaley Bridge dam reservoir could collapse

[Bucket on wheels]

https://www.bbc.com/news/uk-england-derbyshire-49231384

 

[Charlie]

Talk about being lucky with the weather!

 

[V8Druid]

Pam's old mob - Canal and River Trust (as it's called now) .... obviously had a leak for some time looking at the wash out ....
posted some pix of a similar 'situation' with the local canal a while back ... once it starts to infiltrate and create a course ... you're in the s**t .. if it isn't spotted quickly.

TBH they're very lucky .... that sort of event is usually fast and catastrophic and this 'un'd have been on a GRAND scale .. if it'd actually breached, rather than the infiltration they've had .... the high speed water flow over the slip was just the last straw and sucked the slip surface away from the void below it ...

Julie Sharman, who's lead on the situation is very good at what she does and an engineer to boot .... Pam's old boss and have met her a few times ... she really knows her sh1t and is probably one of the best they have, to deal with this ... she's had 'some practice' before

 

[Mogman]

Only 30 miles from me

 

[Left hooker]

My thinking would be coffer dam piles driven in around it then pumped to work on it

 

[V8Druid]

My thinking would be coffer dam piles driven in around it then pumped to work on it

think the main concern ATM is to be seen to be doing A LOT, quickly Stu .... repairs'll come later ... for now they'll want it empty and controllable, with as minimal a risk of a breach as possible .... that word strikes fear into the hearts of all canal workers .. they've seen too many and this'd be on an unprecedented scale, in comparison to a 'deep ditch' breach.

have had three around here, in my memory and jeeez don't they make a bloody mess .... luckily no lives were lost in any of them, but down to pure luck .... being a contour canal, the Mon & Brec is usually way above the surrounding topography .... and water only flows one way


guess who that is, stood closest in the last pic

 

[JD450A]

My thinking would be coffer dam piles driven in around it then pumped to work on it

If it's a clay fill dam with earth mass/banks which it looks to be and it's suffering from infiltration then using piles before the water is down to nothing is a bad idea indeed, could easily cause liquefaction leading to a sudden and immediate collapse.

All there doing now is adding mass to the collapsed section in order to restore the weight in that section. on that type of dam Mass is what keeps it in place and prevents the Clay center from moving/keeps it water tight.

will be interesting to see what happens in the near future.

 

[Left hooker]

think the main concern ATM is to be seen to be doing A LOT, quickly Stu .... repairs'll come later ... for now they'll want it empty and controllable, with as minimal a risk of a breach as possible .... that word strikes fear into the hearts of all canal workers .. they've seen too many and this'd be on an unprecedented scale, in comparison to a 'deep ditch' breach.

have had three around here, in my memory and jeeez don't they make a bloody mess .... luckily no lives were lost in any of them, but down to pure luck .... being a contour canal, the Mon & Brec is usually way above the surrounding topography .... and water only flows one way

View attachment 8099View attachment 8100View attachment 8101View attachment 8098
guess who that is, stood closest in the last pic

I would get in there build a coffer dam around damaged area and over pump the overspill from main lake and from inside piling 2 birds one stone as they say

 

[V8Druid]

If it's a clay fill dam with earth mass/banks which it looks to be and it's suffering from infiltration then using piles before the water is down to nothing is a bad idea indeed, could easily cause liquefaction leading to a sudden and immediate collapse.

All there doing now is adding mass to the collapsed section in order to restore the weight in that section. on that type of dam Mass is what keeps it in place and prevents the Clay center from moving/keeps it water tight.

will be interesting to see what happens in the near future.

Cock on there Rory, with that summary ..... all they'll want to do ATM is get it empty, if only to reassure Joe Public of the removal of the flood risk .... and to negate any chances of it getting away from them

 

[Left hooker]

 

[JD450A]

Cock on there Rory, with that summary ..... all they'll want to do ATM is get it empty, if only to reassure Joe Public of the removal of the flood risk .... and to negate any chances of it getting away from them

That's it.

Once empty your into conventional earthworks... a quick bit of Geotech to ensure the center is still secure and provided that's the case a simple bit of filling and compacting of the failure, followed by a concrete cap for the spillway.

 

[V8Druid]

That's it.

Once empty your into conventional earthworks... a quick bit of Geotech to ensure the center is still secure and provided that's the case a simple bit of filling and compacting of the failure, followed by a concrete cap for the spillway.

absolutely ..... all about PR when it comes to this sort of public works ... especially when you've had a few go before