Do we need to bring back the NRA

[Dicky.A]

Correct dredging helps. Those Dutch lads soon reclaimed plenty of land from the sea.
Grandad started off farming on the banks of the tidal river Ouse. Tens of barges a day would serve industry in City, stirring up silt and sending it out to sea with the tide. He said it was only ever Ings land that flooded and it soon dispersed, leaving nutrient rich silt behind. That was in the days when a flood defence system was a spring loaded flap!
I would rather take a lesson from an old boy than a degree waving hipster fresh out of Uni.

 

[Hesston4860s]

Even the IDB’s hands are tied to a certain extent re weed cutting and de silting, I was talking to one of the digger drivers last year and he said they aren’t allowed to take everything out due to some EU ruling !.

 

[holwellcourtfarm]

I accept that in tidally constrained systems capacity is a big issue as all of the water has to be discjarged on the limited low tide windows. Likewise with pumped discharges the capacity of the channel feeding the pump is critical. Most of Britains rivers are not like that though, certainly the Don in Sheffield and Doncaster is not.

In ordinary gravity discharge rivers the change in flood peak between no silt and 30 to 40% siltation is often too small to measure.

 

[holwellcourtfarm]

Even the IDB’s hands are tied to a certain extent re weed cutting and de silting, I was talking to one of the digger drivers last year and he said they aren’t allowed to take everything out due to some EU ruling !.

Water Framework Directive

Setting out rules to halt deterioration in the status of EU water bodies and achieve good status for Europe’s rivers, lakes and groundwater.

ec.europa.eu

 

[Gill Horse]

I accept that in tidally constrained systems capacity is a big issue as all of the water has to be discjarged on the limited low tide windows. Likewise with pumped discharges the capacity of the channel feeding the pump is critical. Most of Britains rivers are not like that though, certainly the Don in Sheffield and Doncaster is not.

In ordinary gravity discharge rivers the change in flood peak between no silt and 30 to 40% siltation is often too small to measure.

I live in a pumped area and quite frankly the EA are a waste of time.
What's the point in having a fantastic infrastructure of pumps and waterways if the water can't get to the pumps because everywhere is silted up.
As I've stated earlier local farmer's want to help by offering to dredge but the EA threaten them with fines if they do. It's madness shear madness. There are thousands of acres of potatoes, carrots and greens going to waste because the land is waterlogged just because the EA won't allow a few kilometres of the main waterways that feed the pumps to be dredged/desilted. Most waterways upstream are clear because the farmers have cleaned them already but it's no good if the last link in the chain is broken so to speak.
It's very frustrating and it's hurting a lot of businesses, especially when it could easily have been avoided.

 

[Gill Horse]

Again as I have said earlier, I know it's impossible to stop all instances of flooding and I genuinely feel for the people whose homes have been flooded. It must be devastating for them.
But it's also outrageous when properties next door to me flooded because the water course is so badly silted up the water just flows down the main road instead!!!!!!!!!!

 

[Green grower]

Here in Spalding we were flooded in July water would not flow and kept backing up drainage board engineer said pumps at Fosdyke had not enough water to keep running!
Problem was weed growth in drains holding back water after 3 days of being a total pain to them thay put in a 360 excavator 2 days of cleaning problem solved
When the last wet session started we feared the same would happen again back to being a pain with them contacted local farmers and the drain was cleared in a couple of days clear run for water best drainage we have had for years!!!

 

[dowcow]

The public are a pain at times too. I've seen several that treat the ditch behind their garden as a place to put lawn clippings. One place with horses used to shove horse manure under the fence onto the side of the ditch, and I've heard of others first removing their fence and then proceeding to fill the ditch in to gain a bigger garden.... because the farmer has another fence at the other side of the ditch.

 

[Gill Horse]

The public are a pain at times too. I've seen several that treat the ditch behind their garden as a place to put lawn clippings. One place with horses used to shove horse manure under the fence onto the side of the ditch, and I've heard of others first removing their fence and then proceeding to fill the ditch in to gain a bigger garden.... because the farmer has another fence at the other side of the ditch.

The favourite thing they like to do here is build decking out over the ditch.
Not only does it make cleaning the ditch a problem
But eventually the whole lot collapses into the ditch and blocks it!!!!!!!!

 

[onthehoof]

Easy enough to see here how lack of dredging affects flow, what do folk who think dredging makes no difference think the flow on this river will be like in 20 years time?

 

[Gill Horse]

You often see larger deposits of sediment on bends
I'm guessing that the water slows as it goes round the corner and that allows the sediment to settle ?

 

[Hindsight]

Easy enough to see here how lack of dredging affects flow, what do folk who think dredging makes no difference think the flow on this river will be like in 20 years time?

View attachment 843180View attachment 843181View attachment 843182

I think that is Denver Sluice? If so the straight watercourse is the Relief Channel. And the one with sediment is the tidal Great Ouse. So in that case be good to hear from a hydrologist / Drainage person of that sediment is actually an issue. I suspect it may not be? But I do appreciate I am on this thread paddling the wrong canoe! Cheers.

 

[Dicky.A]

See EA getting some stick on news for not dredging the Don. Despite been told it needed doing.

 

[Northern territory]

Not read the whole thread but our 2 mile stretch of fast flowing river is a joke. Planted up with willow probably 30ish years ago, load of them now overgrown and cracking off blocking river in several spots every year. They go on about silt but it just carved big chunks of riverbank away every time it floods. Zero maintenance, send 3 blokes with clipboards out before they would come anywhere near with a machine. All they seem bothered about in this area is bloody going round with there impressive little mowers, mowing riverbanks which is completely pointless in my eyes.

 

[Exfarmer]

You often see larger deposits of sediment on bends
I'm guessing that the water slows as it goes round the corner and that allows the sediment to settle ?

This is how oxbows form, the river flow goes round the outside of the bend, speeding up as it does so, cutting into the bank. On the inside the water slows dropping sediment, the bend slowly goes further and further out until eventually the river makes a new cut through and leaves the oxbow as a lake.
anyone arguing that silt deposition makes little difference to flow has zero knowledge of hydrology or even basic plumbing. Not only is flow restricted but it is also slowed by friction and turbulence.
of course once the sediment has built to the point where daylight reaches the bottom rushes and lilies start to take over and quickly trap far more sediment.
the river at the bottom of my garden , the Blackbourne, a tributary of the Ouse , was popular with canoeists ten years ago, now it is virtually impossible to navigate as it is choked up with vegetation. 100 yards away there was a port with links to Kings Lynn taking cargo till the 18th. C.

 

[ShooTa]

id agree but it would need to be combined with the need for everybody to be hording every bit of rain that lands on their ground - half the problems we have with flooding are caused after rivers are forced into unatural corridors and preventing from flooding in their natural position - buildings on flood plains beingthe key idioting thing. The new raft of farmers grants here in wales mention the good that landowners happen to do without doing anything - ie their land is holding water capacity -slowing the water getting into streams and rivers - not letting that precious topsoil run off down towards the sea....wierdly those chaps over in permaculture land with their swales and whatnot have it right - trees and contour ditches high up in the landscape feeding ponds is a cracking start - who wouldnt want to keep more stock up high.

 

[turbo]

To the ones who say dredging doesn’t work,could you tell us how Holland manages or have they thrown in the towel like we have! After all they are covered by the same eu water framework that the ea says stop us from maintaining the rivers

 

[digger64]

This is how oxbows form, the river flow goes round the outside of the bend, speeding up as it does so, cutting into the bank. On the inside the water slows dropping sediment, the bend slowly goes further and further out until eventually the river makes a new cut through and leaves the oxbow as a lake.
anyone arguing that silt deposition makes little difference to flow has zero knowledge of hydrology or even basic plumbing. Not only is flow restricted but it is also slowed by friction and turbulence.
of course once the sediment has built to the point where daylight reaches the bottom rushes and lilies start to take over and quickly trap far more sediment.
the river at the bottom of my garden , the Blackbourne, a tributary of the Ouse , was popular with canoeists ten years ago, now it is virtually impossible to navigate as it is choked up with vegetation. 100 yards away there was a port with links to Kings Lynn taking cargo till the 18th. C.

This is whats happening here , the outfalls (which drain away from the river to a lower point downstream which isn't lower anymore ) on the Marsh are at river level even in dry time ,so as soon as there is significant rain it just backs up - it really ain't rocket science !

 

[Lowland1]

This is whats happening here , the outfalls (which drain away from the river to a lower point downstream which isn't lower anymore ) on the Marsh are at river level even in dry time ,so as soon as there is significant rain it just backs up - it really ain't rocket science !

I agree if you contain a river to an unnatural path as the with the Witham after Lincoln then you must maintain the path you have chosen either by dredging or raising the banks. Otherwise the River will silt up the path chosen and attempt to do what it should do naturally either meander or spread out across the flood plain. I got an A at Alevel Geography so I know these things.

 

[dt995]

I agree if you contain a river to an unnatural path as the with the Witham after Lincoln then you must maintain the path you have chosen either by dredging or raising the banks.

Don't rivers naturally move around anyway, hence oxbow lakes and the like (I too remember geography lessons , so if you want it to stay in any path you have to consider maintaining it.