Defending against nature


#1

It’s been baffling listening to people talking and watching reports about protecting about floods and that money hasn’t been spent on flood defences.

What baffles me is what do you do and where do you do it?
Currently northern England is sufferring, but we’ve had Welsh border areas affected and Somerset, where next? 60 odd years ago tides etc conspired to cause massive flooding along the east coast there has been measures taken, but on visits there aren’t massive walls along the coastline just in case. Which is what flood defences would be about.

One way to mitigate flooding is dredging rivers and watercourses, but it seems eu legislation to protect wildlife habitats prevents this, which came to light as not dredging was cited as a cause in Somerset. But they have since dredged and they haven’t had news making problems, but then they may not have had any problems.

The problem with a flood defence is that whatever you do, build 10ft high walls along every river bank to prevent overspill? Hardly picturesque given many places affected rely on tourism. Build walls and the flow will increase and any detritus picked up will cause damage, as seen a few years ago when bridges and existing defences were damaged by things caught in the flow. Do you allow floodplains to be just that, but then there will be rural areas affected with villages and farms flooded and roads made impassable to make a few townies happy. I’d bet they’d complain if the road they wanted to drive down was closed and they had to go out of there way. In our area there are places that once a few inches of rain have fallen, flood, and no one bats an eyelid, not even the local press. The people who live there all take their own precautions and have done for years, as part of the insurance requirements.

Geography is something you can’t do anything about, flat low-lying areas will flood easily, live on these and there is always the potential for flooding and the western Lakes is susceptible to extraordinary rainfall given the geology and greography means short relatively steep, rivers and hard rock run off.

I’m waiting for a few weeks and we get an unusual foot or so of snow causing chaos and people saying we should have fleets of snowploughs all over the country and then who knows once it melts. I think we have to accept that nature will, every so often, throw things at us, that make life difficult for a while. There are plenty of places in the world that suffer far worse than we do in terms of weather extremes and natural events.


#2

Totally agree with you.

The main problem is, of course, the media and by that I mean TV. The pictures you get on the news are of two sorts, either one or two people up to their knees in water looking grumpy , or a shot from the air showing a lot of countryside under water.

The first shot is selected out of a number and features the people being grumpiest; no great news story in someone saying to camera “Well, this happens every other year, so we are quite used to it. 'Tis a great place to live otherwise”. TV selects the extremes and makes the World believe that it is the average.

The shot from the air looks dramatic, but those of us who fly know it is not uncommon for flood plains to be, well, flooded. The water is only an inch or two deep and the land is used for purposes that take that possibility into account. The villages are noticeable by the groups of houses apparently on islands where our ancestors wisely put them, joined to the outside world by roads also slightly higher than the fields.

It turned out that the floods a couple of years ago on the Somerset Levels (maybe a clue in the name?) only really affected a couple of dozen families, tough on them, but hardly a national disaster. Rather than attempting a King Canute act and trying to keep the waters back, might it not be better to spend the money rebuilding the houses to be flood proof?

I live halfway up a steep hill with no flood problem, but when it snows it turns into the Cresta Run. I do not expect the government to level the hill, we just make sure there is a few extra tins of beans in the cupboard and wait for a bit.

Isn’t it strange that after a real disaster they extend the news coverage and cancel other programs, but when there is very little news they never shorten the broadcast.


#3

Don’t believe the general press. There’s a very enlightening article around which talks about changes to farming legislation which was done when the government changed. Around five years ago a critical report was issued saying do something now of face issues. In summary the industry was de regulated allowing farmers to do a lot more as they wish, and a lot of that “cheaper action for more output” has the immediate effect of buffering up the soakaway land. Now the top soil is more compact causing faster run off. Apparently.


#4

theres not much you can do when you get so much sustained rainfall, however the above about landscape management is entirely correct - the upland areas, which are where the vast majority of the run off flowing through Leeds, York etc… come from should be able to act as a sponge and not only absorb a great deal of water, but release it slowly into the river systems at a rate that the flood defence programmes can cope with.

however, to be effective, those upland areas need to be a patchwork of forest and bog. bleak, heather-clad, windswept, empty moorland areas absorb very little rainfall, and instead of acting like a sponge, they act like a watershoot.

if the Pennines, from the High Peak to Hexham, were forested and bogged, then the realese rate would be far slower, meaning there would be far more slack in the flood defence system to cope with events like we’ve seen.


#5

I cannot find a very recent BBC article, but it outlined some of the huge inconsistencies relating to subsidies / penalties / benefits to land.

For example, Weksh farmers could be fined or paid subsidies for planting trees; the lesser density is “good” for farming but bad for flood prevention:

Likewise, different subsidies or grants are changed or cancelled, often with a detrimental outcome if you are looking at the prevention of flooding:

Left hand knowing what right hand is doing??


#6

I don’t think the action of farmers will have much impact, although conflicting attitudes/responses to myriad swathes of legislation doesn’t help, the biggest problems are
planners allowing building on floodplains and then people paving over gardens to use for off-street parking or to just get rid of gardens as they can’t be @rsed with gardening.


#7

The communities flooded in the North this last few month don’t really have swaths of housing estates which have caused the flooding. The flooding has happened down stream after the rain has entered the watercourse higher up stream. Have a look at the flood maps - they’re indisputable.


#8

I’m not sure I have ever understood this problem. Most of my front “garden” is paved over with block paving, which allows off street parking. It allows a good amount of rainfall to soak through the blocks or between them. Any run-off there is goes into a drain and thence to a soak away which is pretty much under the paved area. As far as I can see the water is going to the same place (the aquifer) with even less chance of surface run-off than if the area was grass/potatoes/apple trees.


#9

Encouraging water to hit the drains means it flows faster into water courses. When this combines with all the other water in the drains flowing into water courses it passes the ability of the water course/river to handle it. Allowing it to soak into the big sponge that is the soil means it holds onto the water for a while while it passes slowly into the water course.


#10

But the water from my garden only flows to a soakaway which is under the paving, from there it soaks down through the ground to the aquifer. The water doesn’t go into either the sewer or the stormwater (road) drain.

The added advantage is that with enough rain to otherwise saturate the top layers and cause run-off, the soakaway absorbs it and trickles it slowly down into your “sponge”. In general domestic rainwater drains do this and don’t go into the water courses.


#11

I see what you mean now. Those will generally be the exception, especially where local building planning regulations stipulate it on new builds or significant renovations.


#12

It’s bean the traditional way of dealing with rain water for a long time. My father was a builder.

I will admit that it doesn’t work so well on the Somerset levels, though!


#13

Trandition vs popular and cost. When there are peak building projects (and when i mean peak, i mean more than 3 semi’s) builders favours whacking down the foundations, main connections and then splashing tarmac for off road parking as it was considered more favourable for buyers to have off-street parking - especially in towns. Dropping in a soak-away wasn’t on their list of high prorities because it cost more money. You can still have your fancy tarmac driveway AND put in a soak-away but why injur your bottom line? When building regs made it a requirement because no-one was bothering and local flash flooding became more prevalent they had no choice. Also, a soak-away is only useful if your sub surface can handle it. In clay driven deposits, there is often a higher water table making soak-aways useless unless you go down deep to get to more permeable strata. IIRC there was a could of issues with some collapsing as well.


#14

There are many areas where simplification/improvement/integration of legislation/grants would benefit.

Improvements to the countryside aspects would probably be the most complex - one area (EU framing subsidies?) might encourage removal of hedges/trees/ditches in order to maximise the output (of whatever is the popular “product” of the decade) whereas local grants for tree planting conflict with the maximum output mentality.

For urban areas, building on/near areas at risk from flooding should only take place if the buildings are constructed with “flood-proof” features (or the high-tech but expensive option of having a house that raises up on floats. The Dutch seem to have managed it - although the “move away from the river” option would be controversial. Boris had an idea for London, haven’t heard anything recently

I doubt if the run-off capacity would have helped with the vast excesses of rain recently, but I would welcome a new building standard so that all properties had to have “grey water” tanks installed under the garden/property to use the rain water from roof guttering for the toilet/washing machine water functions, etc. If installed during construction, the costs are kept to a minimum (no VAT too) & if it became a required standard so that all properties had to have this, the costs of equipment (currently not produced in huge bulk for domestic houses) would fall. Same applies to insulation, triple glazing & solar power, etc. Via one of my work colleagues, I believe that all new domestic construction in the Netherlands will have to meet energy neutral targets (end of this decade or sooner?). You can also get a higher mortgage amounts from some banks if you commit to guaranteed energy-neutral propositions; that’s quite clever - you get money to help save (energy) money.

This seems to tie in with a proposed EU Directive about “nearly zero energy building” - the UK seems to be slacking somewhat, merely zero carbon!!


#15

A bloke I know who works on a farm said it’s no wonder there has been so much flooding. He told me they stopped clearing ditches as they have to protect wildlife habitats and what they drag out is now regarded as waste and has to be (due to eu regs) disposed of ‘properly’ at huge expense, when previously it got put the land and ploughed in. I have to say a number of back roads lined with ditches near to us get a layer of water on more regularly, when it rains and not particularly heavily. He reckoned if many of rivers and dtiches in the north had been cleared as they once were, there wouldn’t have been problems to the extent there were. He said the irony of the classification of dredging as waste, is that hundreds of thousands if not millions of tons of silt will be dumped on the land after the flooding recedes and get ploughed in or be worked into the soil naturally.

Looking at the zero energy buildings, who pays for the maintenance / upkeep of the installed energy sources etc? Would underground ‘grey water’ tanks need pumping out?
Two of our neighbours had solar panels fitted and have moaned that keeping them clean costs more than what they are supposed to save, as they need to have a proper scaffolder in. It’s all well and good having ideas like this, but the benefits have to benefit to the buyer.


#16

The home owner of course.

Bear in mind that depending on the energy source(s), the maintenance could be minimal - or less cost than the upkeep of a normal central heating system (no annual boiler safety checks, etc). Also, depending on the type of heating that you use, there are other advantages - no radiators or pipes = freedom to place furniture anywhere, no painting of radiators, etc, required.

Obviously, the point of a “zero energy” house is that maximum insulation & near-zero heat loss (or input) is paramount… At rest, the human body pushes out about 100W. Zero energy houses often have to “lose” heat!

The overall combination of best energy products (triple glazing insulation with appropriate glass, solar panels, heat pumps, heat exchangers, etc) can very soon pay for themselves. Mercedes Benz, Tesla & others, think that home “power batteries” are a very good way to maximise your “self-generated” electricity storage.

Grey water - there is a BSI - yes, you would need to include filtering & simple chemical treatment, but these costs are estimated at about £20-£25/yr. To install on an existing property - estimates are for a 10 yr payback; for a new build, much less.

You can install a simpler system that uses shower/bath water for the loos.


#17

Ref panel maintenance…
My water heating ones are serviced every five years (change fluid and repressurise system) by the original installation company and the PV ones don’t require regular maintenance. Both sets seem to keep clean by themselves (rain).
I am sure that there are companies that take advantage of people ref maintenance.