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The River Teifi’s “Toxic Tsunami Of Sludge”

May 28, 2017

By Paul Homewood

h/t Philip Bratby

David Rose updates the story of the anaerobic digester spill on the River Teifi last December:


You would struggle to find a lovelier view anywhere than that from Pencefn, a hilltop farm near Tregaron in mid-Wales.

Lush meadows with sheep grazing peacefully roll down towards the valley of the Teifi, renowned for its salmon and sea trout. Close by are the Cambrian Mountains, where the river begins its journey at the limpid Teifi Pools.

But dwarfing the main farm are the towers and tanks of an anaerobic digester. The Government-subsidised ‘green guzzler’ turns animal excrement, human food waste and specially grown rye into methane gas, which is burnt in a generator to make supposedly environmentally friendly electricity for the National Grid.

This stretch of the River Teifi was affected by the release of a slurry-type effluent from an anaerobic digester

This stretch of the River Teifi was affected by the release of a slurry-type effluent from an anaerobic digester

Last December, just a few months after it was built, the digester triggered an ecological catastrophe.

Unnoticed by the farm’s owners, brothers Jim and William Lloyd, a pipe from a storage vat sprang a leak.

Thousands of gallons of black, toxic slime began sliding slowly downhill across those verdant meadows to a nearby stream – a tributary of the Teifi. The result was a poisonous ‘tsunami’, a flood of putrid sludge that flowed down the stream and into the river for hours. The consequences were devastating, and are likely to last many years.

This week, an investigation by this newspaper has revealed:

I According to local experts, the effects of the spill are so deadly, the river may take years to recover, so ruining the local economy;

l At least 1,000 mature trout and salmon were found dead immediately, but the full toll will be many times higher;

l Poison levels in an eight-mile stretch of the Teifi were so high almost no living things survived;

l The fly-fishing season should be in full swing this month but long stretches of the river are devoid of anglers;

l Lavish Government ‘green’ levies on fuel bills mean Pencefn’s owners – despite being the source of the deadly leak – will continue to reap tens of thousands of pounds in subsidies, while also paying nothing for their own electricity;

A Facebook user and local to the area posted this photo of a dead fish in the river after the spillage. At least 1,000 mature trout and salmon were found dead immediately

A Facebook user and local to the area posted this photo of a dead fish in the river after the spillage. At least 1,000 mature trout and salmon were found dead immediately

l Despite this generous Government support, no official agency checked the plant’s design or safety systems before it was built, or monitored its operation;

l The ultimate cause of the leak was shoddily installed plastic pipework – and both firms responsible have now gone into liquidation;

l Although the Pencefn leak is at least the 20th ‘serious pollution incident’ caused by an anaerobic digester since the beginning of 2015, scores of new ones are being planned across the country – some of the biggest by ‘green’ tycoon and former ‘new age traveller’ Dale Vince of Ecotricity, who advises Labour on its energy policy.

The impact of the Teifi spill soon became apparent. Late on Saturday, December 17, locals noticed the river was covered with a foul-smelling, bubbly slick below the town of Tregaron.

Because it was dark, it was not until the following morning that the source was located at the stream flowing down from Pencefn. Local fishing guide Steffan Jones walked the riverbank shortly after. Dead fish were everywhere.

At the confluence with the Pencefn stream he said he could ‘clearly see the stain of the effluent about five feet above the river level. The stain had discoloured the bank all the way down to the water. I walked the whole stretch of the contamination – seven or eight miles – and the scale of this disaster was horrifying. It wiped out every living thing in the river for eight miles’.

This anaerobic digester power plant had a pipe failure which resulted in a large effluent spillage reaching the Tiefi river last December

This anaerobic digester power plant had a pipe failure which resulted in a large effluent spillage reaching the Tiefi river last December

The slick moved downstream at 5mph, contaminating everything in its path. Residents say that at Llandysul, the most popular angling centre on the Teifi, 30 miles below Tregaron, the river still stank.

Dr Ian Thomas, president of the Llandysul Angling Association, said the timing made matters worse. Mid-December is the peak of the winter spawning season, when salmon and sea trout swim from the ocean to lay eggs in the same pools and eddies where they were spawned. Both the fish and eggs they had laid were poisoned.

‘The whole river has been affected, from the estuary to the headwaters,’ said Dr Thomas.

Natural Resources Wales (NRW), which deals with pollution, said after the spill it had counted 1,000 mature dead fish. But Dr Thomas said there were many more.

Freshwater biologist Frank Jones said: ‘There is still no final estimate from NRW of the total number of fish killed, but it will be a very big figure. Many of the sea trout had not yet spawned, and because they spawn several times in their lifespan this will have a big impact on future generations.

It could be years before they recover.’ He said the fish population, especially salmon, had already been declining because of earlier slurry spills into the river. ‘Slurry is stored in vast artificial lagoons, many of them well beyond their sell-by date. Sometimes they overflow and the slurry goes into the river.’

But the anaerobic digester spill meant it may now pass a critical ‘tipping point’, where salmon will vanish from the Teifi altogether.

May should be the start of the fly-fishing season, and last week there were a few optimistic anglers trying their luck around Llandysul, though none in the toxic epicentre below Tregaron.

Fishing guide Harry Jackson said his business was being hit. ‘Fishing on the Teifi is world famous. Many of my clients come from abroad. But word gets out and hits on my website and bookings for this year are both down 50 per cent. And if people do come to fish but don’t catch anything, then they won’t come back.

‘It isn’t just me and other guides. It’s the hotels, B&Bs, self-catering cottages, pubs and restaurants. The whole local economy is affected – and believe me, this is not a high-income area.’

The value of freshwater angling to the Welsh economy is more than £100 million a year – with the Teifi the biggest source of that income.

Anaerobic digesters have been spreading fast across Britain since 2010. Not only do they leak, they sometimes explode, as one did at Harper Adams University in Shropshire in 2014, when the blast destroyed a sizeable building.

But the gas they produce is classed as renewable green energy, which counts towards Britain’s green targets, hence the enormous subsidies. Some digesters pump their methane to the gas grid and currently receive £216 million a year, directly from taxation. Others, like Pencefn, which supply electricity to the power grid, are subsidised by every energy bill payer.

Pencefn power is sold to the grid at more than double the wholesale market price of electricity. According to Dr John Constable, energy editor of the Global Warming Policy Forum, if Pencefn ran its digester at only half its nominal capacity, it would generate power worth £80,000 a year to its owners, of which £50,000 would be subsidy.

Dr Constable added that the assumption that anaerobic digesters are ‘good for the environment’ seems to account for the staggering weakness of the safety regulations that govern them.

One Tregaron resident, who asked not to be named, said he had been shown around the Pencefn plant before it started operating and wondered about the fact it was next to the tributary stream – with no barrier in case of a leak.

Dale Vince of environmentally friendly energy supplier Ecotricity and adviser to the Labour Party on its energy policy   

Dale Vince of environmentally friendly energy supplier Ecotricity and adviser to the Labour Party on its energy policy 

After the disaster he had discussed it with an NRW official: ‘She told me she would never have advised them to put the digester where it is, and there were no failsafes. I don’t blame the farm owners. When you’re building something so potent, especially when it’s getting all that subsidy, you’d expect you’d have to consult the official agencies. Yet nobody looked at their plans or inspected the plant once it was built.’

Pencefn farm lies at the end of a long, private drive, and when The Mail on Sunday called last week, owner Jim Lloyd agreed to show us around. It was clear he was an unhappy man – and though some locals see him as a villain, he is also a victim.

He took us straight to the tank – about 30ft high and 60ft in diameter – where the leak took place. It was, he admitted, ‘a complete construction failure’ – a U-bend in a plastic pipe that formed the tank outlet blew out under the pressure of the toxic liquid. But because it was underground, nobody noticed until the slime hit the Teifi.

He demonstrated that since the leak, at a cost of ‘tens of thousands’, he and his brother had replaced the pipes with high-grade industrial steel – above ground, where any future leak would be seen immediately: ‘We’ve fixed the problem. It will not happen again.’ Within a month, he admitted, the plant was operating again – and attracting subsidy.

The Lloyds may be prosecuted for breaching pollution laws. They also face civil lawsuits from angling groups and others affected by the devastation.

The river of death’s grim toll…

It was an ecological catastrophe – thousands of salmon and sea trout like the one pictured abover were killed when a ‘green guzzler’ anaerobic digester leaked thousands of gallons of toxic waste into the River Teifi.

And the worst thing about last December’s leak from Pencefn farm in mid-Wales? That the plant, which generates methane gas from animal and human waste, gets tens of thousands of pounds in subsidies paid by every energy bill-payer, but was never subject to inspection. 

But Mr Lloyd said: ‘The problem is, we’re the last man standing now. Both the manufacturer and the contractor who installed the anaerobic digester have gone bust. We believe this was their fault – and there’s nothing we can do. We’re on our own and we can’t sue them.’ Contractor Hallmark Power Ltd went into liquidation on December 16 – the day before the leak. The manufacturer, Combigas UK Ltd, followed suit on March 20 this year.

How did Mr Lloyd feel about poisoning the Teifi? ‘We’re completely gutted about what’s happened. I’m well aware that for our small community and the tourism that sustains it, it’s devastating,’ he said.

Other anaerobic digester leaks have been almost as damaging. In December, the MoS revealed the case of Crouchland Biogas in West Sussex, which has received millions in subsidy yet has operated without planning permission since 2013. It sprang two huge leaks within a year, wrecking the neighbouring farmer’s rare-breed sheep and cattle business.

Yet Mr Vince and Ecotricity – who are not connected to Crouchland Biogas – are pressing ahead with the first of many huge anaerobic digesters it wants to build at Sparsholt Agricultural College in Hampshire.

It had seemed earlier this year that proposed changes to subsidy levels had made this less viable, but Ecotricity spokesman Max Boon insisted: ‘Our position on green gas hasn’t changed. It is a massive opportunity, for the environment and economy, and a viable alternative to fracking.’

Perhaps Ecotricity should talk to the people of Tregaron. One resident asked: ‘How can anyone say this is environmentally friendly?’ He pointed to the bridge across the Teifi. ‘You used to see salmon just there, along with big sea trout. I can tell you, there’s no bloody salmon there now,’ he said.

NRW said that it could not comment because its investigation is continuing.

  1. dennisambler permalink
    May 28, 2017 10:30 am

    “they sometimes explode, as one did at Harper Adams University in Shropshire in 2014”

    I was a student at West of Scotland Agricultural College in the late 60’s and they built an anaerobic digester to dispose of poultry manure from the college battery egg unit. Being Scotland, they had to keep applying heat to even get it working, but it did start and then blew its top on graduation day. It seems there really is nothing new under the sun.

    I am these days a resident of Teifi-land and the cause and the reasons for this disaster have been given minimal local media coverage, so the David Rose article is welcome. All politicians in Wales are signed up to the green Nirvana. and whilst UKIP reject wind turbines, they support the Swansea Bay Barrage, a future white elephant if it happens, as seems more and more likely.

  2. May 28, 2017 11:01 am

    There must have been a lot of incompetence or corruption for the AD plant to be built near a water course without everything being bunded. An EA permit would be required before it should be allowed to operate.

    The AD plant near me polluted the local river before it had even started operation. You couldn’t make up the incompetence/corruption that goes with all “green” schemes.

  3. tom0mason permalink
    May 28, 2017 11:01 am

    “It was, he admitted, ‘a complete construction failure’ – a U-bend in a plastic pipe that formed the tank outlet blew out under the pressure of the toxic liquid. But because it was underground, nobody noticed until the slime hit the Teifi.”

    Plastic pipe!

    Surely their pipes are made of recycled inner tubes knitted together with old socks and old hemp stalks, and later patched with recycled Rizla packets.

  4. May 28, 2017 11:23 am

    Environmentalists seem to major in river destruction. Remember when Colorado’s Animas River ran orange in the summer of 2015? That was brought to us by no lesser an environmental giant than EPA.

    • Mike Jackson permalink
      May 28, 2017 12:56 pm

      Joan, environmentalists major in not giving a **** about anyone else as long as they get their own way. Their definition if what is “environmental” differs fundamentally from that of the rest of humanity and even from themselves in certain circumstances.

      After decades of pollution (when we didn’t know any better and had other priorities) we managed to get the Thames clean enough to accept fish once again. Also the Tyne, which I know better, and doubtless others as well.

      I remember an interview in a local north-east paper with a local eco-warrior who confounded his interviewer by arguing that improving the river was a backward step — not, as you might imagine, because it meant an end to industry and shipbuilding, but because it would encourage people to come to the area to kill fish for sport.

      I haven’t yet heard one of the Brotherhood come out openly and say that the pollution of the Teifi has an upside but I will not be totally gob-smacked if they do.

      Broadly I confess to being in favour of anaerobic digesters as one more means of disposing of waste, provided that is all they are used for. I am emphatically not in favour of using land to grow feedstock for them more particularly since one eco-hypothesis is that we are struggling to feed the world’s population as it is. We aren’t and it is unlikely that we ever will be but I have come to expect this level of cognitive dissonance, aka hypocrisy, from our green friends.

      The idea that anyone’s money, whether as taxpayers or consumers, is being forcibly extracted from their wallets in order to give people like Vince a comfortable lifestyle is obscene. And nauseating with it.

  5. May 28, 2017 12:01 pm

    This is a good example of the technical chaos within the AGW Green Lobby. Digesters are deemed green so throw money at it. Fracking is not so create hassle. The technical aspects and risks being manipulated to suit the agenda.

  6. dearieme permalink
    May 28, 2017 12:05 pm

    “Lush meadows with sheep grazing peacefully roll down towards the valley of the Teifi”: sound more like pastures than meadows to me.

    • Mike Jackson permalink
      May 28, 2017 1:06 pm

      Pedant alert!

      “Meadow” can also mean “a tract of rich pasture-land especially one close to a river.” (Chambers)

      (Sorry, but I’ve just recently been taken to task by another pedant for getting it wrong!!)

  7. May 28, 2017 1:16 pm

    Is the real story that this particular project installed without proper engineering controls, substandard construction and failure to have the proper process monitoring controls? Twenty years ago the common wisdom in the US was to cross the Atlantic to see how the real experts do anaerobic digestion of animal wastes. This makes it almost sound like we could have saved the airline tickets.

    I saw a figure of 249 of these things in the US, I believe there are more. What was described is a medium BTU biogas project going to generators. If you add anaerobic digesters at waste water plants, there are many, many more. There should be nothing new or exceptional about this operation. There is nothing new or exceptional about piping low or medium BTU biogas from landfills. My former employer had 500 dual fuel diesel electric generators burning landfill gas and one high BTU pipeline project. I haven’t heard stories about things like this happening in the US, although I suspect leaks and spills have occurred.

    The article didn’t say what killed the fish and only had a count of 1,000. I assume that the spill killed fish by depleting the river oxygen. The river will return and I guess fairly quickly. I’m surprised there were no comments about restocking or restoration. Fish hatcheries are pretty common in the US, especially around the Great Lakes, which are great salmon fisheries.

    I don’t want to minimize the damage and effect from this incident, but it’s really difficult to wade through the hyperbole in this article and understand what happened. “Toxic tsumami of sludge” gives one the picture of a huge wave engulfing the river and, supposedly, farms and towns. Al this from a pipe leak in which “thousands of gallons slowly sliding downhill.” Lagoons or content have with “sell-by dates?” And we also have a picture of an enviro staring intently into space. I usually don’t bother with articles with this level of hyperbole, but I couldn’t resist the toxic tsumami from sludge seeping slowly down a hill. Everything but new monsters being created.

  8. AZ1971 permalink
    May 28, 2017 1:38 pm

    As I don’t live in the UK I am going to make some assumptions in calculating how “easy” it would be to fix the Teifi’s sludge problem.

    Assume the sludge moved downstream at the same rate as water flow, i.e. 8 km/hr.
    Assume the Teifi’s mean depth is shallow, e.g. under 1.5 meters.
    Assume that reports of “every living thing in the Teifi perished for an 8 mile stretch.”
    Assume someone has to pay for clean-up.

    A quick fix would be to take a number of individuals, all in tandem and with a floating high-pressure water washer device siphoning intake clean upstream water from behind them, to use high-pressure water to force all of the sludge up from the bottom of the river where continual downstream flow would keep moving it in the same direction. As humans on a clean-up effort, one could, given an average river width of 8 meters, expect that a brigade of 8-10 workers would move downstream ~1 m/minute, perhaps faster. Working 12 hour days, the full 8 mile stretch could be completed in 179 days.

    8 workers @ £15/hour (a reasonable wage for an eco-minded individual) x 12 hr/day x 179 days = £257,760

    Given that the river is worth £100 million per annum, this would be a small price to pay to speed recovery this year alone.

    Or am I seriously bonkers?

    • May 28, 2017 3:00 pm

      There is no such thing as a quick fix in the UK. Your proposal would need an Environmental Impact Assessment, followed by a consultation and the agreement of numerous regulatory agencies. By the time everything was in place and the finances sorted, the river would have recovered by itself and the incident would be a distant memory. But as far as the bureaucrats are concerned, “lessons have been learned”.

      • dave permalink
        May 28, 2017 3:17 pm

        “…lessons have been learned…”

        Maybe, maybe not. That is why you always need a final examination before giving out the certificate!

      • Curious George permalink
        May 28, 2017 3:52 pm

        Can I find the Environmental Impact Assessment for this anaerobic digester somewhere online?

      • May 28, 2017 5:40 pm

        I can’t find one on the Ceredigion planning portal. (Then these things are usually impossible to use.) There would (should) have been one, and it ought to be publicly available, along with conditions, letters of opposition, etc.

      • Mike Jackson permalink
        May 28, 2017 5:50 pm

        Sorry, gentlemen, but as usual you are spectacularly missing the point here!

        Anaerobic digesters are “a good thing” because, well, because they are. They produce methane which is a lot cleaner than coal for generating electricity which is also “a good thing” and if we didn’t have them then all that rotting vegetation would produce methane that we can’t control and everyone knows methane is four times more powerful as a climate change factor even than carbon dioxide and we all know how bad that is.

        In fact it is so important that we prevent this uncontrolled methane from wreaking havoc in the atmosphere that we need to press on and get as many of these digesters up and running and we can’t afford to hang about and wait while the bureacracy drags its heels. These so-called impact assesments were never meant to delay work on vital projects like this. They were designed to protect cuddly things like bats amd newts and to stop greedy capitalists from building supermarkets and houses and roads. Those are what damage the environment, not killing off a few fish here and there.

        Those who say we shouldn’t be growing crops just to feed these thigs don’t understand nature. This is really going green! We are producing genuinely natural electricity not plundering the earth and polluting watercourses and causing earthquakes just so we can keep our computers runnjng and our lights on.

        And talking of shale gas — nasty dirty stuff and not natural and look who is keen to exploit the stuff. These digesters are run by people like Vince and others whose hearts are in the right place eco-wise. They don’t do it to make money which is why we need to subsidise them. Shale is quite different. Who knows what Cuadrilla or that guy Ratcliffe at Ineos might do with the stuff? Probably sell it and make money. Imagine that!

        Excuse me a minute. There is someone at the door, I see a flashing blue light and some men in white coats ………….

      • Stuart Brown permalink
        May 28, 2017 7:05 pm

        @ Mike J – priceless, thank you!

  9. Bloke down the pub permalink
    May 28, 2017 5:53 pm

    Dale Vince is also proposing a digester at Eastington, near junction 13 of the M5. Much of the feedstock for this one will be ‘locally grown’ biomass, which will be brought in by hundreds of tractor loads. All very environmentally friendly I’m sure. With his other pet project, Forest Green Rovers, having won promotion to the football league, I suspect there will be pressure on the authorities to allow the digester, as it is part of a development that includes a new stadium for FGR with easier transport links than the existing ground in Nailsworth.

  10. May 28, 2017 8:27 pm

    Reblogged this on Wolsten.

  11. roger permalink
    May 28, 2017 10:37 pm

    The damage done is not only the to the obvious stock of mature salmonids in the river but also to to the juveniles of year classes nought one two and possibly three, including smolts depending on the time of year that this occured.
    Furthermore, the orgamisms that are the food species of the salmonids will also have been destroyed and both will take years to be replaced through natural cycles.
    Wind turbines have also been destructive to upland salmonid populations through alkaline events from concrete pourings for foundations and subsequent leaching, and massive interference with the hydrology of upland bog areas caused by foundations of roads substantial enough to bear the weight of the constituent loads leading to each turbine on the site.
    But never mind, Prince Charles has held an auction to provide funds so as to discover what has caused the precipitous decline in salmon and sea trout stocks over recent years.
    Oh! And did I mention the whales that beached and died due to their ‘radar’ being affected by the offshore arrays in the North Sea? That could not have affected the salmon also could it?
    These people really piss me off.

  12. Russ Wood permalink
    May 29, 2017 8:36 am

    Just remembering a visit to New Zealand, where they take water pollution really seriously. I read an article in a local paper there that reported on a farmer being fined a huge amount for not having sufficent sealing on his effluent dam, allowing animal waste to leak into a stream. Yet this digester was able to get away with a MASSIVE leak in the UK!

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