SHETLAND PEAT SLIDE WAS AN OMINOUS WARNING

A massive peat slide took place in Shetland on 7^th May. A spokesman for Scottish and Southern Electricity Networks (SSEN) confirmed that the slip happened “in an area of hillside between Upper Kergord and the B9075, where work on our Kergord to Gremista Connection Project is taking place”. SSEN has now stated that the site has been closed while safety checks are carried out. There is little doubt that the catastrophic slide, which luckily caused no casualties, resulted from disturbance of the peat bog during ongoing construction work on the Viking Wind Farm. There have been warnings that such a calamity would occur for years. There was a similar massive landslide at the Derrybrien wind farm site in the Republic of Ireland in 2003 and also at the Meenbog wind farm in Ireland in 2020. Indeed, there was a previous peat slide at Kames Ridge in Shetland in July 2022, again at a Viking wind farm site.

Peat slides cause great damage to the environment. Peat is a strange geotechnical material, with extremely low density and an exceptionally high water content.  Once disturbed long runout landslides can often develop.  Especial care is needed to avoid instability in areas of blanket peat coverage. At the Meenbog wind farm in Ireland, the enormous landslide involved rafts of bog with intact and upright trees sliding along a low angle slope, over a very long distance, all the way to a major watercourse.  Thousands of tonnes of peat and debris cut a swathe through the landscape and poured into a stream that is part of the famous River Foyle system, turning the waters black. Local fishers said the catastrophe had all but killed off the important spawning beds for salmon and trout, wiping out fish and all invertebrate life. They fear the river may never recover.

Peat is a global carbon sink, storing millions of tonnes of CO2 during the thousands of years the bog is formed from rotting trees and plant material. However, the first thing a contractor does before erecting a giant wind turbine on peatland is to drain the area, thus releasing all of the stored CO2 into the atmosphere. The peatland is also subsequently destroyed as a carbon sump, stopping any further carbon storage. Damage to peat can extend as much as 250 metres on either side of turbine foundations and access-road installations. So, the whole peat bog will gradually dry out over the years resulting in an ongoing release of carbon. This can easily be calculated once the total extent of the planned development is known using the fact that peat contains 55 kg carbon/cubic metre – three times as much as a tropical rainforest! The whole hydrology of the area will change forever and once damaged, peat can never be replaced – a terrible legacy to leave to future generations and a loss of a critical carbon sink. Over one sixth of the world’s blanket bog is located in Scotland, despite the fact that we have only one sixtieth of the world’s total landmass.  Peatlands form a crucial part of the world’s air conditioning system. They are Europe’s rain forests! Peatlands and wetland ecosystems accumulate plant material under saturated conditions to form layers of peat soil up to 20 metres thick – storing on average 10 times more carbon per hectare than other ecosystems. Peatlands occur in 180 countries and cover 400 million hectares or 3% of the world’s surface. Scotland has a unique role to play in preserving and maintaining this global resource. 

The problem is that many giant wind turbines in Scotland are erected on deep peatland, causing immense damage to the environment, and releasing vast quantities of CO2. Because peat bogs are agriculturally unproductive, farmers and crofters are only too keen to sell or rent their peatland to big power companies, who regularly trot out ‘experts’ to say that peat bogs will be protected and damage to the environment will be minimised. To suggest that a windfarm can be built without draining peat first is just pure moonshine. As soon as the roads have been built and construction of the giant turbines takes place, the peat will be breached, and drainage of the peat bog will occur naturally. This is basic hydrology! Drains will then have to be installed to take excess water off the site – otherwise the area will flood. This is called peat run-off and it will continually flow into adjacent watercourses, causing potentially the deaths of many freshwater and marine organisms as a result of suffocation.

Taken together with the construction of the mammoth steel towers, huge metal sails, vast concrete foundations under every turbine, borrow pits, drains, connecting roads, overhead power-lines and pylons, the carbon footprint from every windfarm built on deep peat far exceeds any environmental savings it may aspire to. Wind energy certainly has a role to play in a diverse renewable energy mix, but it must be properly planned and sited. The power companies’ experts claim that they will construct ‘floating roads’ across the peat bogs, as if they have invented a way of defying gravity. To construct a ‘so-called’ floating road across a peat bog requires huge volumes of stone and hardcore as a foundation. But this stone causes damage to the upper layer of peat, thereby impacting on its hydrology. 

Floating road-construction traffic for wind farms will involve regular passage by vehicles with payload capacities of 30 tonnes and after turbine construction, crawler cranes of up to 250 tonnes. Thus, the necessary thickness and weight of the road makes subsidence into the peat over time unavoidable. When the road surface subsides, it has to be topped off with more aggregate to maintain a level running surface, which in turn adds additional weight and compression to the underlying peat. Under continuous and long-term use, floating roads on deep peat eventually sink to the underlying solid mineral layer, essentially becoming a cut-and-fill type track with peat displaced to the sides.

The calamitous peat slide in Shetland should act as a final warning to SSEN and other big power companies. Scotland’s peat bogs are a precious resource that will take centuries to renew. Digging them up to erect giant industrial wind turbines is daft.