The answer to the floods?

ohanzee

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Won't be long till the water shortage is the next environmental catastrophe, maybe joining up the thinking between too much and not enough is a solution, that's my answer to floods anyway.
 

shropshire_lad

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Won't be long till the water shortage is the next environmental catastrophe, maybe joining up the thinking between too much and not enough is a solution, that's my answer to floods anyway.
It's a nice idea but difficult in practice mainly because how do you engineer and store the water at times of surplus? In my old job, I worked on a few ASR schemes - ASR stands for Aquifer Storage & Recovery. The basic idea is you pump river water into aquifers at times of excess and then it's available in the summer at times of shortages, drought, etc. The other solution is build more reservoirs but these takes ages to get planning for because of objections, etc. Also, I'm not sure either would help manage flooding as the water quality may be unacceptable due to turbidity and the quantity excessive.

They do capture floods in the Middle East with Wadi dams.

Climate change poses it's own challenges with changing weather patterns.

My own overriding opinion, as suggested already by some on here, is we have to work with nature rather than against it.
 

ohanzee

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It's a nice idea but difficult in practice mainly because how do you engineer and store the water at times of surplus? In my old job, I worked on a few ASR schemes - ASR stands for Aquifer Storage & Recovery. The basic idea is you pump river water into aquifers at times of excess and then it's available in the summer at times of shortages, drought, etc. The other solution is build more reservoirs but these takes ages to get planning for because of objections, etc. Also, I'm not sure either would help manage flooding as the water quality may be unacceptable due to turbidity and the quantity excessive.

They do capture floods in the Middle East with Wadi dams.

Climate change poses it's own challenges with changing weather patterns.

My own overriding opinion, as suggested already by some on here, is we have to work with nature rather than against it.
Difficult yes, and too expensive nowadays, I can't help think that without the Victorians and the infrastructure they left we would be living in mud huts by now, the problem is if we can't do these things there is not much hope for averting the damage nature can inflict on us.

How do we work with nature?
 

Secret Angler

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the dredging doesn't always work, it was tried in Northern California it was found to make the river move faster causing bank erosion, now in CA you are not allowed to rebuild within certain distances from a river bank and certainly no builds on flood plains,yet here in the UK planning permission has just been given for thousands more houses to be built , on flood plains? there must be a clue there in the statement, some developers don,t care as long as they build houses.houses on stilts may be the answer, its hard lines on the people who do have the regular floods, easker1
And also it delivers more water downstream to where there has been no dredging, moving flooding elsewhere. It has often been pointed out that loss of flood areas upstream (building, concrete, etc) has caused flooding further down.
 

Reg Wyatt

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Yes it's not about moving water downstream as quickly as possible but rather in as controlled and safe manner as possible. This often means deliberately holding it back in water meadows and on what used to be rather cleverly called, flood plains.

Reg Wyatt
 

shropshire_lad

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How do we work with nature?
Generic I know but respecting natural processes such as Reg mentions above (natural attenuation) and trying to avoid engineered solutions. Engineering solutions such as flood defences appear to just move the problem elsewhere. Respecting the protection that environmental evolution has provided such as flood plains and not covering them with hardstanding. More SUDS (sustainable urban drainage schemes), etc. There's a post earlier where someone references enhancing natural river morphology rather than culverting, etc. That kind of thing.
 

ohanzee

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Generic I know but respecting natural processes such as Reg mentions above (natural attenuation) and trying to avoid engineered solutions. Engineering solutions such as flood defences appear to just move the problem elsewhere. Respecting the protection that environmental evolution has provided such as flood plains and not covering them with hardstanding. More SUDS (sustainable urban drainage schemes), etc. There's a post earlier where someone references enhancing natural river morphology rather than culverting, etc. That kind of thing.
Nah sounds too complicated for the current government following, no one is going to vote for that, rephrase it to include immigrants or something.
 

shropshire_lad

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Nah sounds too complicated for the current government following, no one is going to vote for that, rephrase it to include immigrants or something.
Spot on. Brexit appeared to me much about finding a scapegoat for perceived misfortunes and there are similarities with flooding (although I obviously have huge sympathy for those affected). People tend to look for easy solutions such as dredging, flood defences and the like as per the OP. The real issues, for example development in floodplains and the impacts of possible climate change, are put on the "too difficult to handle" list.
 
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spidernymph

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Because the government doesn't want to explain there is no cost effective answer to the question of flood plains flooding so they're going to do nothing to solve the problem long term. What they will do however is let the people demand dredging and then do a limited amount of dredging as it's not massively expensive, compared to building flood defences, and thus give the impression the government is listening to the people and doing it's best for the people and they can keep trotting out the 'once in a hundred year event' line.
The proverbial nail was hit on the proverbial head above.
 
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Juneau

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Cast your minds back to the great flooding furore at the Somerset Levels where flood water stood out in the fields for weeks. I remember seeing a large photo in the Telegraph taken from the air. There was flood water stretching as far as the eye could see but also stretching as far as the eye could see and clearly marking the course of the river was the top of the two flood embankments - one on each side of the river. It was a remarkable picture.

The point is that the flood water was trapped out in the fields. It had overtopped the embankments at its peak and then when the river level dropped, there it was stuck for weeks with nowhere to go. The ideal solution would have been to cut gaps in the embankments to allow the river to flood out into the fields under control and then when the river begins to drop the water would drop back into the river at the same rate.

The Americans did this years ago on the Mississippi and it saved New Orleans from massive flood damage. It was done as a last resort of that occasion but they realised the value of it. Due to those flood embankments the Somerset Levels flooding was largely self-inflicted.
 

mike fox

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Cast your minds back to the great flooding furore at the Somerset Levels where flood water stood out in the fields for weeks. I remember seeing a large photo in the Telegraph taken from the air. There was flood water stretching as far as the eye could see but also stretching as far as the eye could see and clearly marking the course of the river was the top of the two flood embankments - one on each side of the river. It was a remarkable picture.

The point is that the flood water was trapped out in the fields. It had overtopped the embankments at its peak and then when the river level dropped, there it was stuck for weeks with nowhere to go. The ideal solution would have been to cut gaps in the embankments to allow the river to flood out into the fields under control and then when the river begins to drop the water would drop back into the river at the same rate.

The Americans did this years ago on the Mississippi and it saved New Orleans from massive flood damage. It was done as a last resort of that occasion but they realised the value of it. Due to those flood embankments the Somerset Levels flooding was largely self-inflicted.
 

Elwyman

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Most of the suggestions about dredging are rubbish. An expert said most of the dredging we used to do was to make the lower reaches of rivers navigable for ships. It may still have a place in places like the Fens and the Somerset Levels.
Faster flowing rivers, like the ones we tend to fish for trout and salmon, and generally self cleaning due to the flow velocity.
The environmental impact of unnecessary dredging would be appalling, and the effect on flooding generally negligible.
Flood storage reservoirs are probably the only practical engineering solution for many UK rivers.


Edit Just read the CIWEM link in the post above and I agree entirely with its views.
 

bobmiddlepoint

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Cast your minds back to the great flooding furore at the Somerset Levels where flood water stood out in the fields for weeks. I remember seeing a large photo in the Telegraph taken from the air. There was flood water stretching as far as the eye could see but also stretching as far as the eye could see and clearly marking the course of the river was the top of the two flood embankments - one on each side of the river. It was a remarkable picture.

The point is that the flood water was trapped out in the fields. It had overtopped the embankments at its peak and then when the river level dropped, there it was stuck for weeks with nowhere to go. The ideal solution would have been to cut gaps in the embankments to allow the river to flood out into the fields under control and then when the river begins to drop the water would drop back into the river at the same rate.

The Americans did this years ago on the Mississippi and it saved New Orleans from massive flood damage. It was done as a last resort of that occasion but they realised the value of it. Due to those flood embankments the Somerset Levels flooding was largely self-inflicted.
The Somerset Levels have numerous pumping stations so the water isn't trapped in the fields once it has over topped the flood banks. In fact at times it is pumped out onto the fields to prevent flooding elsewhere. Once the level in the rivers drops the floodwater is pumped back into the rivers. Where it all falls down on the Somerset Levels is that most of the land is at or even below sea level. So once the fields are full and the rivers are full there is nowhere to pump the water. Water can only get out to sea at mid to low tide. During periods of very high rainfall there just isn't enough time at low tide to get all the excess out to sea and then everything floods. The only thing that works is pumping the water out to sea and that was never part of the Levels set up so in the huge floods pumps were brought in (from Holland I think) to pump water to sea at all tide states.

So the Somerset Levels flooding is not self inflicted, it is simply inevitable during periods of extreme rainfall and without the flood banks the whole lot would be under water all the time.


Andy
 

ohanzee

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Found ma pics, some flood rediness here, an 1882 drain worthy of Brunel reinstated, found under a hundred years not clearing, dug it out, emptied, scraped, poked and...works a treat, raised it up to 2020 ground level and stuck the grill back on, good for another hundred years..


IMG_1725.JPGIMG_1727.JPG
 

flyfisher222

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I was watching question time on BBC last night and during a discussion about flooding etc somebody in the audience said, "Just dredge the rivers like we used to do. That will immediately solve all the flooding problems. Dredge the rivers." The environment minister was on the panel but other than applause there was no other comments or denial of the ridiculous thought.
How in this day and age does the question of dredging rivers as a solution still come up. Why has it not been properly explained? The UK general public seems so completely uninformed about causes and limited solutions available reference flooding and the general movement of water.
I'm not necessarily looking to blame anybody but rather question why there is not more of an education drive about our at times rather wet country. In the meantime my thoughts go to people suffering the tragedy of flooding.

Reg Wyatt
It's a perferctly reasonable answer.

People wanting to protect their own interest, as we all do.

It was applauded but not commented on. Because from the point of view of the audience it didn't need to be.

And you are a member of the "general public" too, as are we all. There's a whole lot of things that have not been "properly explained" to you.
 
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Paul_B

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Going back 50 odd years, we had a chap in our village who bought an old cottage for peanuts as it was in a flood area, he made downstairs into a wet room and lived upstairs.
I wonder if it would be practical to add another story to some of these that flood now and do the same.
 

mebu

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Reading the post above regarding the flooding in the Somerset levels: felt sorry for the EA man, in answer to the local farmer who complained about lack of dredging, saying it would increase greatly flooding in Bridgewater town , downstream - " do I look like I give a sod about flooding in Bridgewater?"

Peter
 
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