11. Restoring the Moss

The geological map below shows the complexity and drama of the relationship between the peatlands of the raised mires (pinkish-brown), the boulder clay or glacial till (dark blue) and the Solway Firth.

(The map is ‘Created by RSPB. RSPB Licence 100021787 (C) Crown Copyright RSPB permit No. 60271. Based upon British Geological survey 2006, Solway East Special Sheet, with the permission of the British Geological Survey’)

Cardurnock geology rspb bgs rsz

The main activities that gave rise to these patterns happened at the end of the last Ice Age, 8000-10000 years ago (see The Making of the Solway Firth) during the dance between the sea and the land – but the patterns are still capable of change, and the stage is set for further action: Alasdair Brock of Natural England worries that “Sea-level rise could cause further erosion around the Bowness peninsula …”.

Meanwhile, maps old and new show that Bowness Common is criss-crossed by tracks and the lines of former ditches. Aerial photos of the perimeter show the rectangular shapes of former peat awards and stints, pale areas edged by the dark lines of growing heather; on the ground the hagg, or raw edge of a peat-cut, is as sharp and vertical as a low wall.

RX and SJR to N
Looking North from Rogersceugh. (C) James Smith

All those human interventions, however small, will have affected in some way the interconnectedness of the parts of Bowness Common. Even the interventions on the drumlins have had an effect.

Edges and islands

These ‘mineral islands’ rise above the peat; towards the North is the tiny drumlin where the SJR passes through the cutting, an island now defined by bracken, birch and willow that grow along the track and trace the paths of the drainage ditches. Close to the line of the railway towards the South is the much bigger Rogersceugh drumlin.

The now badly-decayed house and farm- buildings are the remains of a Lowther ‘planned farm’ (Peter Messenger, 1974, Lowther Farmstead Plans) and the slopes of the drumlin itself are bright green with pasture, on which cows graze – and defaecate.

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The drumlin of Rogersceugh, looking North-East: note rectangular water-filled bunds and ring-ditch. (C) James Smith

The drumlin has the shape of a cuttlefish,  a conical body fringed with an undulating fin. Aerial views show that the whole is ringed by a ditch, that has drained the lower skirt of peatland ; here the soil thrown up by moles is dark, friable peat – pick up a handful and very little water can be squeezed out.

molehills dry peat
Peat-y molehills

The ring-ditch empties into a deep terminal drain which was blocked in 2004/5 and dammed in order to re-wet the dry lower fields.

In October 2016 Alasdair Brock and I walked through the fields on our way to the line of the railway track. This was my first insight into the extraordinary complexities of restoring wetlands and raised mires. We talked, again, about raised mires being ombrotrophic and low in nutrients – and he explained that the nitrogen (those cows!) and phosphate in the ‘improved’ farmland would remain high for a very long time; as re-wetting took place and the water-table rose again, the ‘gro-bag effect’ of these elements would cause the wrong types of plants to grow.

We skirted rectangular bunds along the line of the ring-ditch; these had been built by the RSPB to slow the mineral-rich water that was draining off the drumlin onto the edge of the Moss. Eventually, the RSPB hope that sedge-beds and willow carr will replace the pasture, increasing the habitat for breeding waders; later still, Sphagnum mosses should re-colonise the area, growing above the fenland plants to ‘encapsulate’ the phosphate layer.

The RSPB also owns land South of Rogersceugh’s drumlin, and alongside the SJR track to Whitrigg. Previously I had, by chance, met Dot Harrison who formerly lived in the farmhouse, and she had told me that this land had been pasture where her cattle grazed. The grassland had grown on drained and dried-out peat, but for the past 10 years has been undergoing re-wetting by a system of bunds and blocked drains.

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Memories of farming: bench donated by the Harrisons who previously farmed Rogersceugh

The degraded pasture and the mineral-rich edges of the railway track are already spiky with rushes, Juncus; lagg fen is developing, and Dave Blackledge of the RSPB told me that Sphagnum is colonising one corner – but returning the fields to mire could take “tens if not hundreds of years.” Starting from a long way down, one needs to take the long view.

As for the degraded northern edges of the Moss, the RSPB have been busy there too. The charity bought North Plain farm, a mixture of raised tidal flat and ‘mineral fields’, in 1995, and concentrated on ‘wetting-up’ the land by blocking ditches and making lakes, managing the water-level by means of drains and sluices to attract birds like lapwing, redshank and grazing pinkfeet geese.

“But then we started looking for opportunities to get more land, to rehabilitate the bog edge,” Dave Blackledge explained. “The SSSI designation only refers to the intact bog and Natural England [as the statutary body managing the SSSI] isn’t in a position to buy up other areas – but the RSPB as a charity can get in and try to buy.” They now have strips of Bowness Common by Biglands farm, and other ‘edge’ pieces; the project to re-wet the edges, to keep water on the peatlands, is ongoing.

“We’re trying various methods, it’s a bit ‘suck it and see’, but we’re getting a range of habitats coming back. But the bog is the really important thing here – and the edges.”

Curlew nest in the bog and bring their young to the edges to feed. Snipe have increased enormously at the ‘east block’ along Rogersceugh track. The RSPB and NE “work well together” for their common cause.

Joining up the dots

The geological map clearly shows that Bowness and Glasson Mosses are connected, even though a road and strip of pasture separates them now. The surface of Glasson – and thus its underlying hydrology – has  been considerably degraded by peat-winning and NE has a major and ongoing task to restore the mire.

Across the road from Glasson and along the track to Rogersceugh Crossing and the Solway Junction Railway, NE and the RSPB are working on re-wetting the dry peaty pastureland to the South. Another challenge is the land to the North of the Rogersceugh Crossing track that was owned and prepared by Fisons for peat-winning.

lidar RX
LIDAR image. Rogersceugh bottom centre; rectangles show Fisons’ land; blue shows South dam

Ditches with flow-control pipework, and bunds, installed by Natural England more than 10 years ago, now hold back the water.

Cores show the peat is still 6 metres deep in this section: perhaps it will be possible to join the north and south sides hydrologically, to return them to contiguous Moss.

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Peat-coring July 2016

But all the re-wetting schemes described above are trivial, even unexciting, compared with the re-wetting of the Moss along the SJR.

Re-wetting the SJR

Alasdair Brock walks fast, striding across tussocks and boggy hollows. We leapt a ditch, crawled under barbed wire (white fur hooked on the wire was “from the last pensioner I brought here” – said with a grin at my own hair-colour), and suddenly we were in a place of still grey water and the stark relics of trees.

In the 1990s, British Rail sold back much of the SJR land to Natural England; by then, Fisons had pulled out of Bowness and Glasson too.

By 2003, Natural England had brought in contractors to carry out some bunding and minor blocking of drains.

In 2006/7, surveyors, engineers and contractors – Hopes and Land & Water – were tasked to create a series of dams at three sites along the line of the SJR: near Bowness station, near the central mineral island, and at Rogersceugh Crossing. (It’s interesting to imagine how much more quickly James Brunlees, and Waring Bros. & Eckersley, would have constructed the SJR across the Moss, given today’s technology and equipment.)

At the Rogersceugh end, window-sampler coring for the southern-most dam (Dam A on the White Young Green data) found mainly soft peat and ‘wood fragments’ and the corers reached clay at about 4 metres.  But at the site of Dam B a little further North, cores in the ‘made ground’ found a gravel of coal and brick fragments and one core found ‘large pieces of wood’ at about 2.5 metres below ground level; the clay boundary here was one metre deeper. It’s tempting to think the wood might have been relics of the wooden sleepers.

It was in this region, too, that Alasdair Brock and Frank Mawby found traces of limestone, ash and coal: Frank speculates that some of this might have been slag – perhaps used as ballast – from the Workington ironworks. What is astonishing (and very disappointing) is that, despite all these excavations along the SJR, almost no remains of the permanent way have been found.

Dam-building was a major (and very photogenic) exercise: Alasdair’s photographic record of the dam-building is extensive and dramatic.

The reasoning behind the dam-building is that, instead of flowing away from the Moss and being lost, water would now be captured. The water-table to the West of the track would rise, and water would also be able to seep through to the East. “The water-table has to be just right, not too high and not too low,” Alasdair said. “If we get the water table right, Sphagnum will grow”.

In places the dams have been placed right across the track from one longitudinal (1-chain) drain to the other; elsewhere just the drains would be blocked. Dams were made with on-site clay or peat, or with sheet steel piles. Elsewhere, corrugated plastic sheeting was embedded across the track so that the track itself wouldn’t act as a conduit for water. The water-level in the dams is maintained by flow-control pipework.

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Photos of dam construction all (C) Natural England, with thanks to Alasdair Brock

Even more dramatic is how quickly the escaping water was captured, how quickly the ponds grew.

Photos (C) Natural England, with thanks to Alasdair Brock

With their roots becoming water-logged, the birches and willow have gradually died, creating a surreal landscape of bare silver trunks and branches on which, when I visited in November 2016, a flock of fieldfares descended to rest, chacking loudly.

Dead trees make good habitat, clear water is good for waterbirds. The railway is turning into fen, with rushes, reeds and willow. There are traces of otter activity beside the south dam.

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***

In the next section of this report, Chapter 12,  is the aerial view of the track of the Solway Junction Railway – James’ beautiful compilation of the results of his drones’ flights.

Swoop along the track, watch mallard scatter, home in on the bog woodland, the ‘mineral island’, the viaduct’s embankment. Pause the video and examine the contours of the Common, the colours of the mosses and heather and bracken…

And then, imagine looking down on the rattle and groan of ore-laden waggons as a steam-locomotive chuffs along the line, between brown, peaty banks and ditches glinting with running water.

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