Building on flood plains

[Alex321]

Guys, construction has come a long way.

Even flying in to City Airport you can see multi storeys built on water.

Just because it can be done doesn't mean it should be done.

 

[classic33]

That's not true as every development must include a water management strategy and has done for years now.

Maybe their strategy is effective at the point where they're building, but with water all you're doing is moving the problem elsewhere. Mother Nature is harder to control than we'd like to admit.

It's part of the reason The Valley is more likely to flood at some point every year now. Once in a lifetime event is now a real threat every year.

 

[Paulus]

That's not true as every development must include a water management strategy and has done for years now.

The flood plain is there to manage excess water.
If you build on the flood plain you send the water elsewhere and it becomes someone else’s problem.
So these new houses may not flood but some poor souls down stream may suddenly find they have a problem.

But it still moves the excess water else where. It has to go somewhere. Think of haw many towns are now getting flooded where years back they weren't.

 

[presta]

All properties that could be affected by flooding can get insurance now.

That's the result of a temporary agreement with the insurance industry that the government will underwrite their losses. It expires in 2030.

That's not true as every development must include a water management strategy and has done for years now.

The problem with diverting flood water elsewhere is that sooner or later you run out of elsewheres to divert it to, and the further you go downstream the bigger the problem gets. It seems to be generally accepted now that the solution is to blot up the water high in the catchment area so that it's released slowly, at a manageable rate, rather than in one short sharp surge.

 

[presta]

Excess water gets pumped out of the drains and onto the Hundred Foot washes where it is more or less out of the way - a good example of the system working well.

Pumps & dykes are designed with a maximum capacity in mind, and if that gets exceeded due to climate change the whole system keels over.

Can I ask how they manage in low lying countries like Netherlands?

They didn't manage in 1953, there were more Dutch that died than British.

 

[Kingfisher101]

I think people have to exercise common sense really and understand that developers etc act in their own interests not for the potential homeowners. If a house has a history of flooding that's not a plumbing failure and/or is built on a flood plain then I personally wouldn't want to buy it. There's other properties to go for.
Even if you have insurance that will pay out that's not the end of the story as it will be really horrible and stressful to deal with.
Also developers will say anything to get a sale.

 

[Mike_P]

A small housing development was built in Markington between Harrogate and Ripon where the issue was resolved by building a compensatory flood basin upstream from the site. Thing was that was all on land on the same farmers ownership so could be done.

 

[Drago]

This has been heavily reported locally and has made the national media. I doubt houses on the Waterside Meadow site are going to be easy to sell now.

 

[Time Waster]

There is no easy solution but there are a toolkit of solutions out there and the issue isn't about should we put should something there or should we not. The issue is that we haven't managed water flows in this country for existing properties that well let alone new builds. However there has been good developments with managed flood systems. So building on a flood plain doesn't in of itself cause the risk, poor design of the water management is the cause of the risk. We've been managing this risk for millenia. Demand just means that it's not as easy as vikings building on a mound or high ground.

Round here there's 70s housing on the flood plain. There's dykes, gates letting water out and a whole load of other mitigations that work. My gran had a house, actually opposite to where we now live, that often used to have a flooded garden. Also it was a bungalow but had a large cavity underneath it because it was built up before the ground floor. This cavity often flooded top, most of the first two years there. Designed for you could say.

However the railway line at the end of the garden was most of the problem. One year they did a lot of maintenance of it and the flooding simply stopped happening. Not sure what they did but the water drained after it and was no longer an issue.

 

[mustang1]

I know that area very well indeed, having lived nearby for some years as a teenager, and not that far away now.

It has flooded multiple times every year since I was first in the area at age 13.

I don't know which is worse, that someone wants to build on it or that the carncil granted planning permission.

More like which person got a backhander or two.

 

[marzjennings]

Just build 'em like they do over here on the coast in Galveston, up high on stilts. I've rented homes like this for summer holidays and I've noticed that over the years the height of the stilts has gone from around 10-12ft to now above 16-20ft as tidal conditions get worse.

 

[Drago]

There is no easy solution but there are a toolkit of solutions out there and the issue isn't about should we put should something there or should we not. The issue is that we haven't managed water flows in this country for existing properties that well let alone new builds. However there has been good developments with managed flood systems. So building on a flood plain doesn't in of itself cause the risk, poor design of the water management is the cause of the risk. We've been managing this risk for millenia. Demand just means that it's not as easy as vikings building on a mound or high ground.

Round here there's 70s housing on the flood plain. There's dykes, gates letting water out and a whole load of other mitigations that work. My gran had a house, actually opposite to where we now live, that often used to have a flooded garden. Also it was a bungalow but had a large cavity underneath it because it was built up before the ground floor. This cavity often flooded top, most of the first two years there. Designed for you could say.

However the railway line at the end of the garden was most of the problem. One year they did a lot of maintenance of it and the flooding simply stopped happening. Not sure what they did but the water drained after it and was no longer an issue.

But nothing is being done here.

Not only that, my previous post using the flats at Newport Pagnell example shows that flood mitigation measures are often ineffective, or at least more store is often placed in their efficacy than is deserved, and those flats are what happens as a consequence.

Don't build on an area liable to flooding the public money doesnt need to be spent on managing the water. It doesn't seem a difficult concept for builders and councils to grasp, but there it is.

It's like Billing Aquadrome up my end. It has been known to flood regularly since the year dot, yet some muppet built a caravan park on it. Every few years it floods, sometimes multiple times in the same year. Still people buy caravans there and then moan when it floods. I mean, whst did they think was going to eventually happen?

If people knew that a site caught fire every few years or was frewuently hit by large meteorites they wouldn't live there, so what drives people to be blind to floodmrisk when buying a property? The stupidity of people, from developers, through to councils, and onwards to buyers that dont do their due diligence, just beggars belief.

One of the very first questions I asked myself before buying the new Drsgo Towers was, "how much altitude is there between the site under consideration and the nearest water course?" Using the wonderful Internet it took barely a minute to establish the answer as 55 metres. Why does no one else show no inclination the check this out? Do they not read the news?

 

[Mike_P]

An issue can be the soil. Locally it is clay heavy meaning water collects above ground leading to flooding - the Sunday of the 2019 UCIs being a prime example; whoever thought putting the fan park tents where they were deserves a honorable Darwin Award; the course could have been arranged so that trade stands were more immediately accessed from pavements/roads. On such land building on it can improve matters as a drainage system goes in draining that accumulated surface water away; that then needs to be tanked so that it outfalls into whatever sewer or river etc without swamping it.

 

[ebikeerwidnes]

When I moved into this house about 10 years ago one of the things I did was check on flood risk

It is flagged as a potential flood risk - but that is the general area and this house is one of the highest and the flood waters would flow down one of the other roads and miss ours

I do wonder whether or not people down the road did that - as their house is where all the water would flow through

luckily the stream that it all goes into is now in a deep culvert that carries on to the Mersey
If it blocks up it is generally where it goes under the road

still - there have been a few houses bought lower down than us - I would have been very dubious of buying any of them!

 

[Illaveago]

But nothing is being done here.

Not only that, my previous post using the flats at Newport Pagnell example shows that flood mitigation measures are often ineffective, or at least more store is often placed in their efficacy than is deserved, and those flats are what happens as a consequence.

Don't build on an area liable to flooding the public money doesnt need to be spent on managing the water. It doesn't seem a difficult concept for builders and councils to grasp, but there it is.

It's like Billing Aquadrome up my end. It has been known to flood regularly since the year dot, yet some muppet built a caravan park on it. Every few years it floods, sometimes multiple times in the same year. Still people buy caravans there and then moan when it floods. I mean, whst did they think was going to eventually happen?

If people knew that a site caught fire every few years or was frewuently hit by large meteorites they wouldn't live there, so what drives people to be blind to floodmrisk when buying a property? The stupidity of people, from developers, through to councils, and onwards to buyers that dont do their due diligence, just beggars belief.

One of the very first questions I asked myself before buying the new Drsgo Towers was, "how much altitude is there between the site under consideration and the nearest water course?" Using the wonderful Internet it took barely a minute to establish the answer as 55 metres. Why does no one else show no inclination the check this out? Do they not read the news?

A lot of people that live in these new developments aren't local but have moved into the area. It's majority of peeps at our Mens Shed are from elsewhere.