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Stuck in a mire of 'glorious' mud – the oozing mess that threatens to cost Westcountry dear

By Western Morning News  |  Posted: January 03, 2013

  • The constant wet weather has resulted in field banks collapsing, as above in Brixton, South Devon, with roads and bridleways turning into streams Pictures: STEVEN HAYWOOD

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Mud might be glorious stuff according to the famous Flanders and Swann tune, but it is also part of the "biggest and most costly story in the Westcountry today".

Those are the words of one of the country's top experts on soil compaction who has told the Western Morning News that much of the region's recent flooding has been directly related to the way in which we treat the ground we walk on.

In purely natural conditions most soils are capable of soaking up large volumes of rainfall, but when they become compacted you can – according to the Environment Agency's principal officer for land quality – dig down in a saturated field and find bone-dry soil just feet or even inches from the surface.

This means the water is not able to percolate downwards which, in turn, means it must run off the fields, taking valuable upper layers of top-soil with it.

This is the dreaded mud we see in swollen red rivers, on roads and in ditches – and, worse still, inside homes and businesses that have been flooded.

"After the water died down we were left with a layer of mud everywhere," said Kenny McDonald, the landlord of the recently flooded Bridge Inn near Dulverton, which was forced to close just before Christmas. "We had an inch over everything – and I mean everywhere."

After countless hours of hard work, he was able to re-open for drinks only on Boxing Day.

He added: "There was mud across the floors and walls and we could see it all over our equipment. We're now fully open again, but it was the mud that did most damage." So what is all this mud doing going walkabout and causing so much damage – and why does the EA's soil expert Dr Richard Smith rate the problem as so severe?

He said: "This is the hidden problem of the countryside – and it is a very big problem here in the Westcountry. It is all to do with soil compaction.

"People see saturated ground and don't realise that, actually, if you dig down it's not saturated at all. I have taken people into a flooded field and gone down less than a foot to show them soil that is bone dry."

As soon as anyone mentions the phrase "soil compaction", inevitably a finger is pointed towards farmers who use heavy tractors and machinery as well as run cattle and sheep on wet ground – but Dr Smith was quick to say he does not criticise people who work the land.

"The problem this year, the untold story, was the really wet summer," he explained.

"The farmers simply had to carry on farming – they had to go about their harvest and sow crops – but it was all done in the wet and that's when the damage is done. Normally you would have a dry period at some stage where you could go in and do something on the land like ploughing, ripping the ground, creating weatherproof seed-beds – all the things farmers have to do to grow crops.

"They can't, by and large, grow crops on compacted ground."

Dr Smith said any amateur gardener would know that soil will not compact into a hard layer in dry conditions, when it remains crumbly and aerated even if walked on. But stomp on your veg-bed in wet conditions and you will soon see the soil compacted into a dense hard layer with water on the surface when it rains.

"This year there's been very little opportunity to work land in dry conditions," Dr Smith added.

"Normally, farmers provide a valuable service when they go out and work the land. But this year things have been different – and if we had this wet weather in the summer and autumn every year, it really would be a disaster.

"We would either just have to stop and not grow anything, or we would have to adapt.

"So we're not blaming farmers – they are a victim of this. In fact, I know some farmers who have sacrificed entire crops so they wouldn't have soil compaction problems.

"But if they do go in and make a mess then you have lots of run-off, and then you have problems."

Dr Smith explained that in the Westcountry's sandstone belt in particular, from East Devon up to West Somerset, there are rivers running red with mud that is actually prime top-soil washed off the fields.

"But sandstone normally has deep, freely draining soils," he said. "In a natural state these soils can accept the heaviest rainfall and never saturate – they have no water-logging and just soak up the rain because they're very deep.

"In fact, sand has infiltration rate of 800mm per hour, and such soils have a run-off rate of just one per cent.

"This groundwater might take days or even years to come out as springs. But if you seal the soil by compacting it, the water then runs off the surface – and what might have taken ages to percolate down might take just a minute or half an hour to flow away across the surface.

"So you have water running off quickly, taking the soil with it. That's why the rivers run red. In their natural state these rivers should run clear."

The mud and silt blocks drains which further increases the flooding problems. So what should we be doing about this 'untold story'?

"The first thing is to understand it and raise awareness – we've got to wake up to this, then adapt," said Dr Smith.

He added: "You either stop growing high-risk crops in high-risk areas, or you can improve land drainage and get the water away underneath more slowly.

"There's been a history of that since the Romans were here, but that has all gone into disrepair during the last 20 years.

"Farmers received government grant aid in the 1970s and 80s for things like drainage, but when we had butter mountains and all the other surpluses a lot of money was withdrawn.

"Yes, farmers can do things to help like use machines with fatter tyres – that helps – and there are different ways of working the ground. But the trouble is when you get a really prolonged wet period.

"I could see this coming (the recent floods) back in the wet summer. But these floods are disproportionate to the rainfall and it is because the ground is sealed and saturated only on the surface.

"We have to re-invest in agriculture," added Dr Smith. "And the money has to be invested in the actual land – because it provides a service to the public. If this was happening, you would be seeing far fewer images of floods in your newspaper.

"You can invest in flood defences – but we also need to do some uphill thinking," he said.

"The sustainable solution is to get our soil in good condition. If you get the soil right, it all comes together. Until then it really is the biggest and most costly story in the Westcountry."

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