Building on flood plains

[Kingfisher101]

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.

Yes, everything will be alright till there's a problem with that and it floods itself or collapses or there's some other problem.

 

[oldwheels]

Our house narrowly escaped as the water level rose once to the top of the downstairs toilet before the tide turned. A neighbouring cottage owned by an elderly couple was not do lucky and the interior was ruined to a height of about 4ft.
I sent a couple of distillery workers over to help them but it took a lot of work to clear up the mess and ruined furniture. Fortunately they were able to get upstairs so were not homeless but we loaned them portable heaters and a stove which helped in the short term.
Not nice.

 

[Mike_P]

Yes, everything will be alright till there's a problem with that and it floods itself or collapses or there's some other problem.

It's been their around 20 years. Possibly done by people who knew what they were doing.

 

[Slick]

I don't disagree with you at all, but it seems that we're not very good at it in the UK?

There was an estate built locally recently which flooded within 6 months despite the developers' assurances that it wouldn't.

There's always an exception but any high profile flooding I can think of recently is long established towns and villages.

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

We've been doing this for hundreds of years.

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.

I don't disagree with that, but we've been moving heaven and earth for hundreds of years to suit construction and much more over the years, like farming and mining. I think if you ask, most people would say that winters are getting wetter although this can vary wildly by area. I find it interesting to speak with farmers who have owned the land for generations, as most of them record weather data specific to them meticulously, and they would tell you that they are seeing areas flood that never flooded before because of rainfall, not construction.

https://www.metoffice.gov.uk/research/climate/maps-and-data/historic-station-data

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.

Again, most of the high profile cases I can think of is from long established water courses.

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

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.

My understanding is that's exactly what a SuDs does.

https://flood-map-for-planning.service.gov.uk/flood-zone-results?polygon=

 

[classic33]

All the water on the hills makes it's way down into the valleys. More and more we're seeing water diverted for the benefit of those living in the valleys.
What were once numerous individual flows have become one larger flow. Either by force of nature or us pushing it where we want it to go. A natural watercourse, that has changed little over the centuries on its own, will be flowing on roughly the same route it did a 100 years ago. Expect where we've altered its course. And we've a track record of doing just that.
This is the point where courses hidden by building, become visible. Often breaking the surface in unexpected places, and trouble "starts".

As far as SuDS goes, two recent plans for housing developments nearby, had very good plans in place. One wanted to run the sewage and surface water off into the local Brook. Across land they didn't own, nor will ever own. Council agreed, environment agency said no.
The more recent one planned on building a pond to take all the surface water, with no means of it going elsewhere. Where it went when full wasn't answered. Again, the council are behind the plan, saying it's totally workable. Any container will only hold a certain amount, then it will find somewhere else to go.

We can move the problem either upstream or downstream to protect where we are, but nature will show who's really in charge.

 

[Illaveago]

It is quite interesting how we can get the opposite effect of flooding as some rivers dry up in the summer as the expansion of towns draw water from either the river or from underground sources. The source of the river Thames has now moved due to such a thing. The river Kennet also almost dries up due to water taken by Swindon .

 

[Time Waster]

Just seen this article about a water flow management project at a Gloucestershire hospital.

Water

 

[Beebo]

Just seen this article about a water flow management project at a Gloucestershire hospital.

Water

800 litres of water! Wow. That will do it.

I appreciate they are trying but that’s less than 1 cubic metre of water.

 

[Time Waster]

Quite! However it's a start of state sector thinking about water. If only officialdom thought more of consequences and mitigation of their decisions.

 

[Bazzer]

As have we, out here in the Fens, thanks to the Dutch. Along with numerous pump stations dotted here, there and everywhere. Plus the big sluice up at Denver.

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. It does mean diversions via Downham Market to get to Welney when the causeway is under water.

Indeed, there are several examples in your area. The Forty Foot Drain and the Coronation Channel are the ones which spring to my mind.

 

[presta]

Flood management on the Today programme here on the Avon at Bristol, from 1:41:32. (8 mins)

In essence, they're saying 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.

 

[Slick]

 

[Beebo]

Beavers is the answer. 😁

 

[Slick]

Beavers is the answer. 😁

There's a joke in there somewhere.

 

[classic33]

Flood management on the Today programme here on the Avon at Bristol, from 1:41:32. (8 mins)

In essence, they're saying 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.

Part of the problem down The Valley is that that was done years ago. Provide water power for the mills lower down.* And to provide drinking water for the growing population.

The man-made watercourses made for these dams haven't been looked after very well over the years. Many now flood into natural watercourses, overloading them.