Left Field

[mc281]

Not sure which category if any to post this but I think it might be an interesting thread..... Maybe.
I was just sat reading the forums here and the flood reports came on the tellybox. My missus turns to me and says... "No doubt all this water will be wasted whilst the natural underground aquifers and water table levels won't increase depth and we'll have water shortages next year!.... Why aren't we (The Brains of our community) drilling holes through the ground to let the water soak into the underground areas?"
I have no answer but no doubt there are some with more brains on the forum who know?...... 1, 2, 3, GO........?

 

[MorrisWoodman12]

Wikipedia Aquifer - Wikipedia has an interesting article about aquifers including the recycle time of surface water. I gather from it that aquifers are generally porous rock so water would only be absorbed very slowly even if it was possible to drill into them. Of course I suppose it could be possible to pump water into them sort of like fracking but what the side effects would be is anybody's guess: contamination, destruction of the rocks, etc.

 

[Fitzroy]

It's all about surface area, there is lots and lots of surface area out there and increasing it a meaningful amount is difficult. For example 1km x 1km of land has a total area of 1 million square meters. A 12.7cm (5") diameter hole drilled to 1000m deep has a surface area of c. 400m2, to increase the surface area of the land by 10%, ie 100000m2 you would need to drill 250 holes.

Other considerations
- expense, at £10k per borehole that's £2.5m per square KM, UK land area is 243,000km2 so a total cost of £610billion, or £61billion if only 10% of UK area feeds aquifers. (NHS budget is £170billion/yr).
- you need to get the water to the holes
- the holes will block up quite quickly with sand, silt and other debris
- the land acts as a filter before the water reaches the aquifer, bypassing this filter would be bad

 

[Agent_zed]

I watch as more and more people tarmac their front gardens to create parking spaces and wonder if we will ever learn.

I was pleased to see the legoland carpark is gravel (in grids to reduce movement - although whether plastic grids are good for the env is another matter) so the water can just soak through.

It's like when the somerset levels floods and everyone wants to dredge the rivers. So the water can move faster to ... um no where as if the tide is high the water has nowhere to go but the 'levels' (aka the flood plain).

 

[treeturner123]

I watch as more and more people tarmac their front gardens to create parking spaces and wonder if we will ever learn.

I was pleased to see the legoland carpark is gravel (in grids to reduce movement - although whether plastic grids are good for the env is another matter) so the water can just soak through.

It's like when the somerset levels floods and everyone wants to dredge the rivers. So the water can move faster to ... um no where as if the tide is high the water has nowhere to go but the 'levels' (aka the flood plain).

When making any planning application now,, one of the things that LAs are very keen on finding out about is how water will be disposed of and, if parking is involved, you must have permeable material. There is now permeable 'Tarmac' for such situations.

Phil

 

[Agent_zed]

When making any planning application now,, one of the things that LAs are very keen on finding out about is how water will be disposed of and, if parking is involved, you must have permeable material. There is now permeable 'Tarmac' for such situations.

Phil

new builds yes, but so many people with older houses seemingly just do it without any planning involved.

 

[Terry - Somerset]

I suspect flooding has more to do with topography.

Water has a tendency to flow to the lowest point available. Most flooding occurs due to run-off either from saturated ground or impermeable surfaces. The former is responsible for most extensive flooding - the latter tends to be more localised - eg: in road dips under bridges.

Rivers run in valleys (really!!) into which flows run-off. Heavy rain simplistically increases the river level by the ratio of the catchment area to river area. This is moderated by the river flow and delays in run-off. But enough rain in a short period will cause the river to burst its banks.

The problem is made worse in urban areas where flow is limited by hard "landscaping" limiting river flows - embankments, bridge foundations, jetties, etc.

Ensuring excess water fills aquifers rather than out to sea requires:

• avoid building on flood plains,
• slow run off with trees etc on hill sides, and
• avoid impermeable surfaces on flood plains.

These solutions have been evident for decades (if not millennia) - mostly studiously ignored by planning authorities and developers!

 

[Phil Pascoe]

new builds yes, but so many people with older houses seemingly just do it without any planning involved.

You need PP for vehicular access and the dropped kerb.

 

[Jacob]

... avoid impermeable surfaces on flood plains

Or anywhere. Better for it to soak away locally rather than hit the drainage syatem.

- mostly studiously ignored by planning authorities and developers!

.....and farmers. Land drainage can be a disaster downstream.
In fact anything which speeds up the passage of water can just makes it worse further down.
Rewilding is one answer which seems to work Stem the floods – don’t hold back rewilding and bring back the beaver!
If laying slabs or flagstones it helps if they aren't pointed in with mortar so the drain in situ with no run off to the drains

 

[Blackswanwood]

It’s called Managed Aquifier Replenishment. As I recall it’s not quite as simple as it sounds as they absorb the water at a much slower rate than it rains during a storm.

 

[Stanleymonkey]

In various parts of the world where beavers have been reintroduce, their ponds slowly recharge groundwater levels in the locality.

Might take up to 5 years but holding back that river water recharges the groundwater and there often reports of streams running all year round and not drying up in summer along with long dried up springs coming back to life.

 

[simonridout]

Flood control is quite simple, hold back water up stream, speed up its passage down stream. The question is at what point on the water course this is done!

 

[MikeJhn]

Did I read somewhere that the Panama Canal is doomed due to Lack of water?

 

[Jacob]

Did I read somewhere that the Panama Canal is doomed due to Lack of water?

https://www.euronews.com/green/2023...-of-the-worlds-most-important-shipping-routes

 

[Agent_zed]

You need PP for vehicular access and the dropped kerb.

It may be a requirement but I would bet a whole lot of money that the houses near me that have paved their front gardens have not done this. One house has entirely resin'd their front garden and drive, there is literally not even a border left where previously there was a probably at least a 15ft x 15ft lawn, it is now just a big carpark.

So many houses around here have little ramps left in the road to go over the kurb either rubber type ones or just made from a large blob of tarmac. Certainly not legal but no one cares.

The council don't have the money or time to enforce and if no one complains then it is not even on their radar.

 

[Jester129]

I've had the frontage to my bungalow resin-bound (they used a cement mixer to coat the stones in resin, then trowel them down like plastering) and it is permeable. Good job, or in a downpour it would have flooded the garage of my neighbour next door!

 

[Phil Pascoe]

It may be a requirement but I would bet a whole lot of money that the houses near me that have paved their front gardens have not done this. One house has entirely resin'd their front garden and drive, there is literally not even a border left where previously there was a probably at least a 15ft x 15ft lawn, it is now just a big carpark.

So many houses around here have little ramps left in the road to go over the kurb either rubber type ones or just made from a large blob of tarmac. Certainly not legal but no one cares.

The council don't have the money or time to enforce and if no one complains then it is not even on their radar.

You don't have our local councillors. The chance of anyone doing it without PP here and its not being reported is zilch.

 

[highwood122]

Flood control is quite simple, hold back water up stream, speed up its passage down stream. The question is at what point on the water course this is done!

i live upstream. planning permission was given for my dwelling with septic tank 70 years ago. rewilding and beavers and councils using these sort of excuses not to maintain ditches etc raises the water table thus spoiling the efficiency of my septic tank and turning the area into a bog. talk your way out of that one city boys

 

[Jacob]

i live upstream. planning permission was given for my dwelling with septic tank 70 years ago. rewilding and beavers and councils using these sort of excuses not to maintain ditches etc raises the water table thus spoiling the efficiency of my septic tank and turning the area into a bog. talk your way out of that one city boys

You need to catch up and build a better septic tank.
"Reed bed" could be the answer in a boggy area, not sure how the beavers would take to it though!

 

[Blackswanwood]

i live upstream. planning permission was given for my dwelling with septic tank 70 years ago. rewilding and beavers and councils using these sort of excuses not to maintain ditches etc raises the water table thus spoiling the efficiency of my septic tank and turning the area into a bog. talk your way out of that one city boys

I’d take some convincing there was merit in a view that prioritising the efficiency of the septic tanks used by a relatively small number of people over the prevention of floods for the many living downstream.

Life’s not perfect - get a better septic tank and enjoy the improved quality of the countryside as it’s returned to how it was.