Floods and droughts?

[Pan Pan Pan]

Watching and reading the various articles on the flooding that has occurred across the UK, and the references to climate change, where droughts are allegedly predicted for the UK in summer, the thought struck me that perhaps a suitable response to this, would be for the UK to build massive new reservoirs, into which flood waters could be diverted/pumped.
This could then help to reduce / stop flooding in the areas that always seem to get hit by flooding, whilst at the same time providing a huge source of water to help deal with the drought conditions some are predicting will now start affecting the UK in the summers to come.
It may seem simplistic, but to me, storing water when the UK has too much of it, for use when it does not have enough seems a common sense approach to both problems.
Of course none of this would be cheap, but comparing a one off payment of billions to build the reservoirs, and the infrastructure required to handle the water, to the millions / billions? needed to pay for the damage that both flooding and drought cause every time they happen still seems like a good deal in the long term. Or is the idea of storing water when we have too much, for use when we don't have enough too silly?

[Pan Pan Pan]

robbieduncan said:

If we are going to create huge reservoirs to store spare water might as well make the suitable for pumped hydro to store energy at the same time too

Indeed I was reminded of the scheme in Wales? I believe where water is pumped up to a newly built reservoir in the mountains, using off peak electricity for the pumps, which was then released to power a hydro elec plant during the times of high demand during the day. So yes, hydro electricity could also be a side benefit of reducing or stopping flooding in the winter, and supplying water in times of drought.
A posted earlier it cannot be cheap, but compared to repeatedly having to pay out millions or billions to mitigate the effects of repeated flooding, or drought conditions, would suggest that in the long term it would be money well spent.

[Pan Pan Pan]

Sophisticated Sarah said:

The idea seems to be that blaming climate change is far cheaper than maintaining or investing in infrastructure. Plus it permits new taxes and bans on fuels that might be cheaper to use.

Sensible option would be better maintenance of rivers to lower the risk of flooding, and better planning of new housing estates so they’re not built on plots of land with cute names such as watery meadows.

Cannot disagree with this, but reducing the chance of flooding in the winter, with better maintenance of rivers, and water courses is not going to solve the issue of the predicted droughts in the summer.
We don't want to just get rid of the water into the sea, we also want to hold onto it for when the predicted drought conditions occur, Apart from extracting some hydro power from the movement of billions of tons of water, the reservoirs themselves could form part of a national park, recreation chain, which would provide further benefits from storing huge volumes of fresh water.

[Pan Pan Pan]

Getragdogleg said:

Local flooding here is caused by the unmaintained drains and gutters filling up with mud and leaves and then simply not working to actually drain water when we do get rain.

Its maintenance that is required.

Water shortages in summer are from too much demand and not enough maintenance on leaky pipes. Infrastructure investment is needed to enlarge or build reservoirs but again the money is not spent.

All true, but I was just commenting on the fact that in winter we seem to have too much fresh water, and (if climate predictions are to be believed) in summer we wont have enough, it just seemed like common sense, to take action that would help to solve both conditions in one go.

[Pan Pan Pan]

My original comment was not really to do with why we seem to be getting floods in the winter, and allegedly droughts in the summer, but more to the fact that that is what we `seem' to be getting.
As posted earlier any scheme which seeks to divert some of the excess fresh water we get in the winter is not going to be anything else but colossally expensive, but when put against a possibly repeating pattern of damagingly expensive flooding, and flood repairs, and loss of crops through both flooding and droughts, it would seem to be common sense to spend a huge, sum now to build the infrastructure needed to store and distribute excess rain water, than repeatedly pay huge sums to counter the effects of flooding and possible droughts every year.
I remember someone in government suggesting that a huge North, South pipeline was built to bring water from the North where there always seems to be plenty / in some cases too much, to the South where droughts hit in the summer, which was met with a comment from someone in the North saying you`re not having oour water. Wonder if that person is still saying that now?

[Pan Pan Pan]

otolith said:

vaud said:

Water is expensive to move. It's heavy (vs gas) - which is partly why we don't have a national water grid.

Also given some of the local rivers were seeing 350 tons / second I'm not sure how we would move that kind of volume?

Of very turbid water with high levels of contamination too.

Water is indeed very expensive to move, but the question is, Is it more, or less expensive to not move it, and suffer flooding in some areas on a repeating basis, and just pay for the damage caused by flooding each time flooding occurs?
Also, if we are predicted to suffer increasing episodes of drought in the summers, will we then have to pay huge sums to pump up, and process sea water into potable water for times when there is not enough?
For some water schemes around the world, handling 350 tons of water per second is just chicken feed.
All water is contaminated, which is why we use reservoirs to store it, and water processing plants to clean it ready for human consumption.
For centuries the more enlightened cultures are those who store a commodity when there is an abundance of it, for use later when there is not enough.
It is just a question of whether we want to pay for water handling, (and damage caused) every time flooding, and droughts occur, or whether we take a (massive and expensive) one off step to store water, when there is too much of it, and in the process, help to reduce, if not eradicate flooding in the winters, and then have it available for use when there is not enough of it.?
It needs someone very clever to do the sums, and work out which approach is best in the long term.
This of course would just be a numbers game, since it would not take into account the suffering caused by those who suffer the effects of flooding, and droughts on their lives and their businesses on a continually repeating basis.

[Pan Pan Pan]

otolith said:

There are degrees of contamination, though. We have significant sewage discharges to watercourses during flood events.

Really, though, I think dealing with those brief, temporary high flows by capturing them and pumping them to storage is a pipe dream.

It may well be, but as pointed out handling 350 tons of water per second is just chicken feed in some countries. We already have the technology to turn raw sewage into drinking water,, so dealing with it when taken from a reservoir of it will absolutely not be a problem (perhaps, wouldn't recommend swimming in it though), Even the reservoirs we have now contain contaminants from just about every source you could think off, and we still manage to deal with those,
Not sure those that have to cope with their homes and businesses, including farms being flooded on a regular basis would feel about it, not to mention those who cannot grow crops, or raise live stock owing to drought conditions, especially when a few months earlier their homes and businesses were under water.
But as I said it would need someone cleverer, than just us keyboard warriors here, to actually work out what would be the most cost effective way forward for the long term.
The costs of dealing with repeated floods and droughts over the long term, could in time, dwarf the cost of delivering a one off solution now, a solution that provides an answer for BOTH flooding and drought conditions at the same time.

[Pan Pan Pan]

vaud said:

Pan Pan Pan said:

Water is indeed very expensive to move, but the question is, Is it more, or less expensive to not move it, and suffer flooding in some areas on a repeating basis, and just pay for the damage caused by flooding each time flooding occurs?
Also, if we are predicted to suffer increasing episodes of drought in the summers, will we then have to pay huge sums to pump up, and process sea water into potable water for times when there is not enough?
For some water schemes around the world, handling 350 tons of water per second is just chicken feed.
All water is contaminated, which is why we use reservoirs to store it, and water processing plants to clean it ready for human consumption.
For centuries the more enlightened cultures are those who store a commodity when there is an abundance of it, for use later when there is not enough.
It is just a question of whether we want to pay for water handling, (and damage caused) every time flooding, and droughts occur, or whether we take a (massive and expensive) one off step to store water, when there is too much of it, and in the process, help to reduce, if not eradicate flooding in the winters, and then have it available for use when there is not enough of it.?
It needs someone very clever to do the sums, and work out which approach is best in the long term.
This of course would just be a numbers game, since it would not take into account the suffering caused by those who suffer the effects of flooding, and droughts on their lives and their businesses on a continually repeating basis.

Alternatively we stop building on flood plains and slowly remove buildings from flood areas rather than trying to fight nature (as with some sea defences)

The question is why are we building on flood plains in the first place? The answer? to meet the housing needs of a small country, with a rapidly growing population.
If we don't build on flood plains (and it is something which I think is daft anyway) where are we going to put the hundreds of thousands of new homes we are being told the UK now needs every year? If we will insist on rapidly increasing the UK population, then we will have to pay the prices involved in doing that. Will we now start building on farmland / green belt areas?

[Pan Pan Pan]

Evoluzione said:

vaud said:

Evoluzione said:

Do we have droughts in this country anyhow? Maybe I didn't get to hear about them or forgot, but certainly we haven't had one up North since the 70s.
We have plenty of reservoirs and water in the North and they are all linked together already so water is pumped around wherever and whenever needed.

Some are linked but not all.

We had a massive water shortage in 1995, which is what lead to many new links. Bradford nearly ran out of water, which lead to emergency tankers bringing water in from Cumbria and water bowsers on some streets.

So in more than 50yrs two close calls which were easily dealt with. Now the infrastructure has been improved accordingly so as far as I can see it's a non issue here.

You appear to only be looking at the past, when given the hiatus from some regarding climate change, it would appear to be more sensible to make preparations for what is predicted to happen in the future.
We cannot control the Earths climate, and we as a small country cannot control what other countries do in relation to it, but we can take the steps to protect the country from the likely / possible effects of it.

[Pan Pan Pan]

Evoluzione said:

Pan Pan Pan said:

Evoluzione said:

vaud said:

Evoluzione said:

Do we have droughts in this country anyhow? Maybe I didn't get to hear about them or forgot, but certainly we haven't had one up North since the 70s.
We have plenty of reservoirs and water in the North and they are all linked together already so water is pumped around wherever and whenever needed.

Some are linked but not all.

We had a massive water shortage in 1995, which is what lead to many new links. Bradford nearly ran out of water, which lead to emergency tankers bringing water in from Cumbria and water bowsers on some streets.

So in more than 50yrs two close calls which were easily dealt with. Now the infrastructure has been improved accordingly so as far as I can see it's a non issue here.

You appear to only be looking at the past, when given the hiatus from some regarding climate change, it would appear to be more sensible to make preparations for what is predicted to happen in the future.
We cannot control the Earths climate, and we as a small country cannot control what other countries do in relation to it, but we can take the steps to protect the country from the likely / possible effects of it.

Well it's a bit difficult for me to predict the future and you too. You seem to think it's going to end up like Ethiopia here when in fact unbeknown to you the infrastructure has already been improved.

Given the flooding some parts of the country have had (which for some, is a repeat of what happened to them only a short time ago) it would seem that unbeknown to you, the infrastructure has not been improved, and if it had been, it clearly has not worked.

[Pan Pan Pan]

Agammemnon said:

Pan Pan Pan said:

The question is why are we building on flood plains in the first place? The answer?

An honest answer is "because some fool will buy it", at which time it ceases to be the developer's problem.

If people didn't buy them then the construction programme would soon end.

I would also add that because the demand for housing has only been going one way, that all the prime sites for new houses have long, long since been used up, and developers are now having to use sites, that not so long ago would have been ignored by them..
This owing to expensive problems related to sub soil conditions, ground contamination on pre industrial / brown field sites, and of course sites exposed to flooding risk.
The issue being that if they do build on such unsuitable sites, there will always be those who will buy them first, and only worry meaningfully about the problems that might arise after they have moved in.

[Pan Pan Pan]

Agammemnon said:

Pan Pan Pan said:

if they do build on such unsuitable sites, there will always be those who will buy them first, and blame everyone else after they have moved in.

Altered to show reality.

Absolutely agree.

[Pan Pan Pan]

I guess we have all seen the huge storm water drains used in the US to carry flood waters away from in cities (e.g as used in second terminator film and the race scene in Grease, which for most of the time remain dry, with perhaps just a little trickle running in a channel for most of the time. As posted before is suspect infrastructure like this is not cheap, but the question I was asking is, do people believe it would be better / cheaper not to build such infrastructure, and just pay for the consequences of a flooding episode as and when they occur, Or would it be better to pay out a huge sum on a one off basis, to build such facilities to protect against future flooding episodes?
As `some' have predicted that we will be getting wetter winters, and warmer drier summers, it just seemed to me that the logical solution to the possibility of both flooding and droughts, would be to capture the excess water (not just get rid of it) in the winter, so that it is available for distribution when we allegedly get hot dry summers in the future..

[Pan Pan Pan]

vaud said:

It is not cheap, and we have an infrastructure legacy that the US did not have in the build out of some cities.

If you are starting with a blank sheet then a lot more is possible.

Absolutely. I doubt if anyone believes that the construction of such infrastructure is going to be anything but colossally expensive, and hard to achieve, no matter how much cash is made available.
However, I wondered that given the `predictions' by some, that these flooding events are `predicted' to be more, rather than less likely to occur in the future, and that we are also `predicted' to be getting more hot, dry summers where the availability of enough potable water for the population may be also problematical with our current water storage capacity, It seems a logical step to construct something that helps reduce the likelihood of flooding happening in the winter, whilst at the same time providing increased water capacity for use in the `hot dry' summers we are alleged to be facing, when it may be in short supply.

[Pan Pan Pan]

slipstream 1985 said:

gazapc said:

slipstream 1985 said:

Re the floods here is my solution

https://goo.gl/maps/3xxtjhqVeVk2CVS66

Build a reservoir here. Link the Severn at the narrow point where they turn away from each other. Dig out the isle area or more it seems like a natural bowl kinda area anyway. Cost some land and one hotel/country house.

Just measured this in Google Earth, if you built a 2km x 0.8km reservoir, with a depth of 5m you could hold 8million m3 of water.
A preliminary google search suggests a historic peak flow rate at Bewdley of 630m3 per second.
All that engineering means you can divert the entire flow for around 3.5 hours, if you want to divert 20% of the flow, you can do it for a bit less than 18 hours.

Thanks for doing the math I'm just an ideas man. There is scope to double or tripple the area nearby and could you go deeper? Tag in a hydro electric planty or two into it and doublle up on it's uses. You could justify using the carbon reducing fund rather than flood defence fund for it.

Perhaps the trick is not to try to divert the entire flow from swollen rivers but to divert anything above normal flow for the time of year, from the rivers into a newly constructed catchment area, in a given area.
Any valley which is dammed to form a catchment area could be many metres deep., A reservoir only 5 metres deep would just be a shallow pond, and hardly worth the effort of forming it.
Such infrastructure would be colossally expensive, but would represent a one off solution that might at least last for a decade but possibly longer, if all that excess fresh water is taken out of it to meet demands during the hot summers some have predicted we are going to get.
But back to reality, we currently have areas that are underwater (again), but give it a few months and we could be getting hose pipe bans, and other water usage restrictions (again)
Just seems we are`nt doing something quite right, when it comes to practically dealing with the `actual' weather conditions the UK seems to getting these days.

[Pan Pan Pan]

We will no doubt be laughing at the irony of having water use restrictions placed on many parts of the country, in just a few months, when we get the predicted `record' hot summers, that those who believe we have messed up the climate, have said are in store for us.