Peatlands are a kind of wetland habitat, but over decades and centuries past, the natural retention and flows of water within the landscape of the Somerset Levels and Moors have been changed by drainage to reclaim the land and use the peat for fuel, compost, or farming.

In 1970 Somerset Wildlife Trust acquired one of the largest remnants of lowland raised bog in the South West, the mire at Westhay Moor.  However, the impacts of the drainage and peat extraction are still evident today. For years the Reserves Team and volunteers have battled the trees, scrub and bracken that are showing us that all is not well beneath our feet. The industrial past of the site, and drainage of the wider landscape has meant that water is draining out of the peat much faster than it should.  As custodian of this rare habitat the Trust has made a bold, new stand to protect what remains.

Without waterlogged conditions the mire is unable to support the open habitat and rare, specialist species that would be found on a natural peat bog.  Neither can it keep the ancient reserve of carbon within the peat safely locked away, because as soon as the peat starts to dry out biological processes begin which release the carbon to the air and water, contributing to climate change.

With funding from the Nature for Climate Peatland Grant Scheme and via the Valencia Communities Fund (through the Landfill Communities Fund), in August 2023 we started a two-year project to remove damaging vegetation on parts of Westhay Moor and begin groundworks to slow the flow of water within and on top of the peat.

The removal of trees and scrub are an important step in the rehabilitation of a lowland peat bog.  Trees damage the peat in two ways.  First, they act as water pumps, removing water from our wetland habitat and transpiring it to air.  Second the canopy acts as an umbrella, stopping rain from reaching the surface of the peat and shadowing rare low-growing peatland species.  These drier conditions are more suited to non-peatland species which then move in, drying the habitat out further spiralling away from the waterlogged conditions a peatland needs to stay healthy.

So once the damaging vegetation is removed, we have been using a rewetting technique called deep trench cell bunding.  This involves digging a trench into the peat, past the dried out upper layers to the healthier, wet peat below.  The peat is then turned over and compacted back into the trench to block up the drainage features in the trench walls.  At ground level small surface bunds have been made to capture rainwater, so that it can filter down into the peatland rather than run off into a ditch. 

Admittedly the project this year has had a few issues, such as the flooding this winter which ironically has made ground conditions too wet for the trench bunding work.  We’ve also had some mice nibbling through things they shouldn’t whilst seeking shelter in the warm, dry engine housing of one of the excavators.

The Big Picture

We have over 2 million hectares of peatland in the UK, storing over 3.2 billion tonnes of carbon but 80% of those peatlands are degraded and losing carbon to the atmosphere contributing to climate change.  By rewetting the peatlands at Westhay Moor we are keeping the carbon locked away and making it more resilient to the effects of climate change and giving our bog species a real chance for the future.

This project work is a big leap forward for the rehabilitation of the remaining peatlands at Westhay Moor and in truth it will take many years and potentially a few tweaks to bring our precious peatland back from the brink.

But the early signs show promise.  Yes, the second half of 2023 was really rather wet, but it is already clear that the areas that have been cleared and bunded on the reserve are holding rainwater very well, and through our monitoring network and the work of our volunteer community we hope that much more positive news will follow in the coming months and years as the groundwater levels rise, securing the carbon and providing a better, wetter habitat for rare peatland species.

Peatlands really are special, so to keep the peat in a bog, not a bag - the next time you’re in the supermarket or garden centre make sure to buy peat-free compost and bedding plants.  Also keep an eye out for products that may be produced with ‘hidden peat’ such as potted herbs and mushrooms.  Find out more in The Wildlife Trust’s Hidden Peat campaign.