Whaley Bridge Evacuated

[Tuscan]

15 minutes ago, carlt said:

We can be fairly sure that when the emergency is over the rebuild bill will come out of CRT's coffers as there is no surplus in boris' Brexit battle budget for such fripperies. 

 

Maybe CRT could apply for a European grant... Oh... Hang on... 

Richard Parry stated on Newsnight that CRT were not short of funds for reservoir works so there should be no problem.............

[roland elsdon]

Boris

Concrete

reservoir

 

idle thoughts

 

[IanD]

It's easy to blame CART for everything as usual, but let's look at what actually happened. An excess of water flowing down the spillway -- a normal event, but maybe never before in such quantities -- managed to penetrate under one of the concrete slabs (which are only thin and there to protect the soil) and lift it up, then it all escalated from there. How would people suggest that CART could have predicted and avoided this?

 

I guess there was no obvious fault on the slabs and this has never happened before so there was no reason to suspect it would happen this time, but maybe that amount of water has never been down the spillway before -- so blame global warming, not CART. Maybe the fault is with the original dam builders who only put thin slabs down instead of much thicker heavier ones which wouldn't have lifted, but then they did last over a hundred years without this happening so that's hardly fair.

 

Hindsight is wonderful, but anticipating a problem which has never happened (with that dam) before isn't easy -- except for the armchair critics who will blame CART for anything...

[system 4-50]

Shouldn't every reservoir have a plughole so that it can be emptied fairly quickly and independently of the normal path into a well-maintained run-off?  Or stop planks? I am prepared to donate a universal travel bath plug that I have not used in years.

[starman]

20 minutes ago, IanD said:

 

....anticipating a problem which has never happened (with that dam) before isn't easy.

But isn’t that exactly what highly qualified people are paid to do? It’s called risk assessment. 

And i know I’m being wise after the event but given the increasing prevalence of heavy rain and flash floods just maybe it wasn’t assessed very well. 

But then foresight isn’t perfect - Grenfell, Boeing 737 Max come to mind. 

[PaulD]

13 minutes ago, starman said:

But isn’t that exactly what highly qualified people are paid to do? It’s called risk assessment. 

And i know I’m being wise after the event but given the increasing prevalence of heavy rain and flash floods just maybe it wasn’t assessed very well. 

But then foresight isn’t perfect - Grenfell, Boeing 737 Max come to mind. 

Interesting examples. Anyone visiting Dubai could have foreseen Grenfell tower as cladding fires were occurring frequently  - except we were assured that our building regulations did not allow flammable cladding to be used. I understand that the pilots foresaw problems with 737 Max. Problem is the qualified people are ignored by politicians and business leaders.

[LadyG]

Brother was here today,he's a Civil Engineer, Consulting Engineer ................. he explained all the ins and outs.

His opinion was  "Sir" Richard Parry was very good, and the Labour MP was not.

I explained that the CRT "struggled" with a canal breach costing £3m.

He opined that the "heritage rights" adopted by CRT from BW could possibly be covered by contract. So let's hope the "Taxpayer" digs deep, and this is ring fenced from general maintenance. One of brother's  colleagues actually does these  surveys, and it seems any recommendations HAVE to be carried out according to schedule. Legally enforceable.

Nothing to do with climate change, foreseeable risk etc etc.

Edited August 2, 2019 by LadyG

[IanD]

15 minutes ago, starman said:

But isn’t that exactly what highly qualified people are paid to do? It’s called risk assessment. 

And i know I’m being wise after the event but given the increasing prevalence of heavy rain and flash floods just maybe it wasn’t assessed very well. 

But then foresight isn’t perfect - Grenfell, Boeing 737 Max come to mind. 

Also Concorde, space shuttles, Titanic and many others -- after a disaster has happened it's always easy to say it should have been caught, but risk assessment is partly based on knowledge and experience of what went wrong in the past and estimates of how likely (or unlikely) something is to happen, it's not an exact science. Some of the ones mentioned really could be blamed on people being careless/far too optimistic/neglectful/ignoring facts/cost-saving, but I don't think the Whaley Bridge dam is one of them.

 

If you want to do a flood risk assessment there are far more places in the UK (where many people have drowned in the past) which are far more likely to have a problem in future than one dam (which has never had a problem), this would be *way* down the list. It doesn't even look like a maintenance problem in spite of what some people have said, it's just something that has never been put under such severe stress before and failed. Hopefully lessons will be learned, but short of spending an absolute fortune dismantling the surface of every dam in the country and looking underneath (to prevent a recurrence of a disaster which hasn't actually happened) it's difficult to see what could realistically be done, there are many far better ways for CART to spend their budget.

[MtB]

1 minute ago, PaulD said:

Problem is the qualified people are ignored by politicians and business leaders.

 

I'd say it is more accurate to say that the people at the coal face seeing the problems up close and uncomfortable (qualified or not) are the ones who are ignored nowadays by politicians and business leaders. Same sort of thing is happening in the medical world, in the NHS. 

 

 

[IanD]

6 minutes ago, PaulD said:

Interesting examples. Anyone visiting Dubai could have foreseen Grenfell tower as cladding fires were occurring frequently  - except we were assured that our building regulations did not allow flammable cladding to be used. I understand that the pilots foresaw problems with 737 Max. Problem is the qualified people are ignored by politicians and business leaders.

And who exactly predicted a problem with the Whaley Bridge dam which was then ignored? Yes there's a town below it, just like many others all over the UK which haven't ever been flooded as a consequence. Mainly because dams are tall and built in valleys, and there's very often a town in the valley below...

 

I did say many of the examples could have (and should have) been foreseen and prevented, but I don't see how this is one of them. It's a difficult-to-foresee accident which -- so far -- hasn't killed anybody or wiped out a town.

Edited August 2, 2019 by IanD

[Athy]

55 minutes ago, roland elsdon said:

Boris

Concrete

reservoir

 

idle thoughts

 

I very much doubt that any rebuilding assistance from state funds would need to be personally approved by the Prime Minister; more likely by a "Sir Humphrey" type of civil servant, surely?

[dmr]

43 minutes ago, system 4-50 said:

Shouldn't every reservoir have a plughole so that it can be emptied fairly quickly and independently of the normal path into a well-maintained run-off?  Or stop planks? I am prepared to donate a universal travel bath plug that I have not used in years.

Spent some time last winter walking round the various reservoirs that used to feed the Rochdale, including Gaddings Dam which is now owned by a group of locals. Avoiding flooding accidents is certainly a big issue when you have water on top of a hill but emergency plugs do not appear to be used, maybe too much chance of accidents or bad teenagers having a bit of fun. The standard method for taking water out appears to be a huge siphon. Dunno how they start them, I think lots of people must need to suck really hard.

 

........Dave

[carlt]

2 minutes ago, dmr said:

. The standard method for taking water out appears to be a huge siphon. Dunno how they start them, I think lots of people must need to suck really hard.

 

........Dave

A bung slightly smaller than the hose diameter is pulled through, sucking the water through with it. 

[MoominPapa]

4 hours ago, starman said:

Even after the torrential downpours there have been, reservoirs surely don't go from safe to bursting in a few days?

Given that torrential rain and  flash floods are increasingly becoming part of our weather  doesn’t this smack of a certain lack of foresight somewhere? 

In this case, it looks like the reservoir level reached the maximum level and the spillway started to discharge high volumes of water, possibly for the first time ever, and sustained damage which puts the dam in danger. It may be that the spillway has deteriorated and become faulty, or has always been faulty since it was added in the 1970s (see, people do consider these things and upgrade 18th century engineering.) In those cases, the dam has been dangerous for a long time, but maybe nobody knew.  

 

MP.

 

[MoominPapa]

Boris

Concrete

reservoir

 

idle thoughts

 

 I very much doubt that any rebuilding assistance from state funds would need to be personally approved by the Prime Minister; more likely by a "Sir Humphrey" type of civil servant, surely?

 

 

Whooosh........

 

MP.

 

[roland elsdon]

Hmm you dont follow my line reasoning clearly. We need something large useless and encased in concrete to fix a hole...

By the way concorde was a great success, till unfortunately one got dropped. My brother in law used to crew in them. Said the saddest thing was them going out of service.

 

 

[LadyG]

43 minutes ago, IanD said:

Also Concorde, space shuttles, Titanic and many others -- after a disaster has happened it's always easy to say it should have been caught, but risk assessment is partly based on knowledge and experience of what went wrong in the past and estimates of how likely (or unlikely) something is to happen, it's not an exact science. Some of the ones mentioned really could be blamed on people being careless/far too optimistic/neglectful/ignoring facts/cost-saving, but I don't think the Whaley Bridge dam is one of them.

 

If you want to do a flood risk assessment there are far more places in the UK (where many people have drowned in the past) which are far more likely to have a problem in future than one dam (which has never had a problem), this would be *way* down the list. It doesn't even look like a maintenance problem in spite of what some people have said, it's just something that has never been put under such severe stress before and failed. Hopefully lessons will be learned, but short of spending an absolute fortune dismantling the surface of every dam in the country and looking underneath (to prevent a recurrence of a disaster which hasn't actually happened) it's difficult to see what could realistically be done, there are many far better ways for CART to spend their budget.

The integrity  of dams is little to do with "examining" what can be seen, it relies on correct construction, essentially a big lump of clay holds the water back, the bits you can see are just "froth"

Edited August 2, 2019 by LadyG

[IanD]

42 minutes ago, MoominPapa said:

In this case, it looks like the reservoir level reached the maximum level and the spillway started to discharge high volumes of water, possibly for the first time ever, and sustained damage which puts the dam in danger. It may be that the spillway has deteriorated and become faulty, or has always been faulty since it was added in the 1970s (see, people do consider these things and upgrade 18th century engineering.) In those cases, the dam has been dangerous for a long time, but maybe nobody knew.  

 

MP.

 

The concrete spillway was added in 1971 following flood damage to the original spillway in 1964 and it being judged inadequate. Presumably at the time the new spillway was assessed as being safe, and in fact it survived undamaged for almost 50 years until the current problem. I doubt that anyone thought it would ever see the massive volumes of water flowing down it shown in the videos because this was never expected to happen. Again, hindsight is wonderful, but I don't see any evidence of neglect in either design or maintenance, the failure happened in unforeseen circumstances.

Edited August 2, 2019 by IanD

[IanD]

12 minutes ago, LadyG said:

The integrity  of dams is little to do with "examining" what can be seen, it relies on correct construction, essentially a big lump of clay holds the water back, the bits you can see are just "froth"

Most embankment dam failures happened because of failure of the clay core, which has not (yet) failed at Whaley Bridge -- the spillway ("froth") is badly damaged but so far the dam is holding. I'd say that meant it was doing its job. And until the spillway failed I doubt that any inspection would have found any problem with it.

 

[Murphy's law says that having said this the whole caboodle will collapse and wipe out Whaley Bridge tomorrow, and everyone will go "yah boo told you so"...]

20 minutes ago, roland elsdon said:

Hmm you dont follow my line reasoning clearly. We need something large useless and encased in concrete to fix a hole...

By the way concorde was a great success, till unfortunately one got dropped. My brother in law used to crew in them. Said the saddest thing was them going out of service.

 

 

You'll need more than Boris to fill a hole that big. Fortunately we're not short of candidates right now... ?

 

Concorde was a great technical success but a business/financial disaster, due to the oil crisis and largely unfounded opposition in the USA because their SST failed to happen. The weaknesses which lead to the crash could maybe have been foreseen (there had been other tyre burst incidents) but since no Concorde had ever crashed nothing was done to fix them.

 

Incidentally the studies that were done more recently for a "Concorde 2" showed that even with the best new technology it would be very difficult to improve on the original -- a lot of the stuff that went into it was not only groundbreaking but still hasn't been surpassed, or even equalled. There's a fantastic (and very long) thread on PPRUNE about this if you're interested and have several hours to spare... ?

Edited August 2, 2019 by IanD

[crossley]

Was in Furness this afternoon on other business, called in to the marina tocheck on the boat. After going through the roadblock on the A6 where police are cautioning people, it was eerie. No trains on the Buxton line, or hope valley line, no road noise, the incessant stream of tipper trucks, nothing. Never realised how noisy it was up there. The levels up a few inches that's all. Hopefully the worst is over now, if it had rained heavily overnight and continued undercutting the embankment, they would have been in real trouble. So hopefully we got off lightly this time. 

[Chris Williams]

22 minutes ago, IanD said:

even with the best new technology it would be very difficult to improve on the original

Some parts of Concorde were produced on this 1912 steam hammer.

[Athy]

2 minutes ago, Chris Williams said:

Some parts of Concorde were produced on this 1912 steam hammer.

Wow, I would have loved to see that working - though not from too close.

[blackrose]

I love this thread. Suddenly everyone's an expert in civil engineering! ? 

Edited August 2, 2019 by blackrose

[Keeping Up]

On the radio this afternoon, they followed the 2pm news report by playing the Dam Buster's march. Maybe Richard Parry should adopt it as his theme tune.

[Jennifer McM]

Earlier in this thread there were questions asked about who's paying for the Chinook - this tweet (one of 10) is interesting - click to see the next 9 tweets

 

 

 

 

Can't believe, with the Chinook flitting about, people are having to asked not to fly their drones. ?

 

 

Edited August 2, 2019 by Jennifer McM