Dangerous Ground

Storm Diana was blowing a hooley around our house this week, bringing lashings of rain with her. You know; the kind of sudden showers that make a dog walk less of a gentle trot and more a thundering canter to get home out of the wet.

As well as Diana’s appearance, a recent FaceBook post of my cousin Andrew’s alerted me to the fact that Turkey has also been experiencing storms but with far worse consequences. The floods are all the more surprising for being in Bodrum, a tourist area that is known for its beauty.

Bodrum floods

Much like my family’s experiences in the two recent Carlisle floods, it seems astonishing that these streets, happily strolled along by families and friends, can be the scene of so much chaos. Then, shortly afterwards when the clean-up operation has begun, they go back to their former selves, looking as though it never happened. The mental scars take longer to heal though and I’m often struck by the seeming innocence of surroundings that I know personally to have seen dreadful destruction.

Floods are never far away from your mind in this part of the world. Living next to a river like the Severn, you’re always aware of its moods and how quickly they can change. At this time of year, the Severn takes on the excess water coming off the Welsh hills, as well as those in Shropshire, and it can rise by several feet in a short amount of time. If you can get close to the water, you realise it’s moving at a deceptively fast pace. It has a beckoning whisper that’s lethally hypnotic.

In time there’ll be another post about the famous flood heights that have been reached by the Severn and the work that’s gone in to preventing them. And there are further, darker tales about how easy it is to drown in the river (the subject of a pretty dreadful folk song I endured at a local pub once). But this post is something a little different. This is about the secrets that are held by the landscape in which we live. This is about how the very ground beneath our feet that we know so well – or thought we knew – can suddenly and dramatically change…

Shropshire is a county rich in geological interest. The county’s most memorable landmark is the Wrekin which can be seen from as far away as Manchester and Gloucestershire. Not far away is Wenlock Edge: a long and geologically unique escarpment that runs for 15 miles across the landscape. And then there is the steep-sided Ironbridge Gorge, containing the swift River Severn that is crossed by the internationally famous and eponymous Ironbridge.

The mighty Wrekin

The Ironbridge was built where there was a concentration of furnaces, fuelled by the charcoal provided by the heavily wooded hills and the minerals mined from within the ground. These natural advantages propelled the invention of cast iron that so changed the world in the 18th century and beyond, but it left its mark on the landscape. The valleys that are now so densely wooded were once stripped bare. The hillsides and any flat ground were peppered with industrial sites and, from the 16th century onwards, there were mines anywhere and everywhere. This constant subterranean excavation, in an area already pretty vertiginous, left trouble lying in wait for later generations.

The Ironbridge of Ironbridge

Even before the Industrial Revolution, land in the Severn Valley was remarkably unreliable but especially so when you add earthquakes.

On 27th May 1773, after days of heavy rains, approximately 18 acres of hillside between Buildwas (about a mile upriver) and Ironbridge slipped its moorings and thundered down into the river below. The mighty flow of the Severn was temporarily halted, upending boats further downstream. Entire copses of trees, several buildings (luckily no people) and the road that lined the bank were shifted many yards south and 30 foot deep chasms appeared in the hillside above.

After a little time the sheer pent-up energy of the river found a way forward through a new channel that was deep enough to carry a boat loaded with 30 tonnes of goods (the first to try the new course). The water surge carried away the boats that had been left on the riverbed, never to be seen again.

The cooling towers of Buildwas Power Station, coloured like local sandstone – to blend in?

Today you simply could not tell that such a cataclysmic occurrence ever took place. In fact, your attention is not drawn to the steep woodland above you as you drive along the road but rather the enormous Buildwas Power Station on the opposite side of the bank. Nevertheless, the landslip is still recorded on the OS map of the area at a site called The Birches, despite it being largely forgotten or unknown by us, the current residents and neighbours of the Gorge.

As you might expect though, it was a matter of great interest to the general public at the time, for its disruption to the economy (the River Severn was an important arterial trade route into the Midlands) as much as it’s Biblical nature. National newspapers ran articles on the astonishing event, thought to have been caused initially by an earthquake. A minister from Madeley, Rev. John Fletcher, gave a sermon at the site the next day to a crowd of about 1000 on-lookers. His first hand eye-witness account is quite something:

“The Birches saw a momentary representation of a partial chaos. Then Nature seemed to have forgotten her laws. The opening earth swallowed in a gliding barn. Trees commenced itinerant, those that were at a distance from the river, advanced towards it, while the submerged oak broke out of its watery confinement, and by rising many feet recovered a place on dry land. The solid road was swept away, as its dust had been in a stormy day. Then probably the rocky bottom of the Severn emerged, pushing towards heaven astonished shoals of fishes and hogsheads of water innumerable. The wood like an embattled body of vegetable combatants, stormed the bed of the overflowing river and triumphantly waved its green colours over the recoiling flood. Fields became moveable, nay they fled when none pursued and, as they fled, they rent the green carpets that covered them in a thousand pieces. In a word, dry land exhibited the dreadful appearance of a sea-storm. Solid earth, as if it had acquired the fluidity of water, tossed herself into massy waves, which rose or sunk at the back of him who raised the tempest. And, what is most astonishing, the stupendous hollows of one of those waves, ran for near a quarter of a mile through rocks and stony soil, with as much ease as if dry earth, stones, and rocks, had been a part of the liquid element.”

Map of the landslide drawn by George Young

Samuel Cookson, a local farmer, reported that his windows had shaken as though attacked by a hailstorm at the same time as the landslide and, that night, further buildings were destroyed by another earth tremor.

However, as time went on, the surrounding landscape failed to move any further and life presumably went back to normal. For almost a couple of centuries at least. Though there always have and always will be landslides, none were as serious as The Birches. 

On Twitter, I follow a writer called Robert MacFarlane (@RobGMacfarlane) who writes daily tweets about the landscape and the meaning of beautiful words. Very recently he tweeted about the “angle of repose”: the maximum angle at which a slope of loose material stays stable, with the bonds of friction just exceeding the demands of gravity. In a figurative sense, it refers to a human life or community and the tense point where sticking together beats falling apart. 

Further down the tweet thread another commentator stated that the angle at which avalanches occur is 38 degrees (which explains the name chosen by the campaign group). Whatever natural occurrence (storm, wind, earthquake, weight of snow or rain) it is that turns that repose into lethal movement can be varied, as it can be in human life, but there will be one thing that tips the weight, the straw that finally breaks the camel’s back. For Jackfield that angle was breached at the beginning of the 1950s, with shocking consequences.

Jackfield lies about a mile and a half downstream from Ironbridge. As well as coal, local clay deposits in the valley and the surrounding area gave rise to some internationally important pottery works such as Coalport, Caughley and Maws tiles (based at Jackfield). Possibly the earliest wooden railway in the country (maybe following the path of the Calcutts Road) was laid here in 1605 by James Clifford, lord of the Manor of Broseley (a town that sits on top of the Gorge), to transport his coal down to the river at Jackfield.

For such a small area, it was vitally important to the local economy and had its own halt on the 19thcentury railway that ran through the Gorge. Jackfield was a long, linear development that followed the line of the river, unfortunately over one of its more geologically unstable areas. By 1950 some of the local cottages nearest the Severn had reported a broken water main, an ominous warning of what was to come.

This excerpt is from the Fourth Rankine Lecture by Alec Skempton in 1964:

…by February 1952 the road was becoming dangerous. During the next month or two the landslide developed alarmingly. Six houses were completely broken up, gas mains had to be re-laid above ground, the railway could be maintained only by daily adjustments to the track and a minor road along the river had to be closed to traffic.”

Although the progress of the land down the hillside was almost stately compared to The Birches, it was more devastating to the residents. Eventually 27 cottages were lost or had to be destroyed and the river itself was narrowed by 15 yards.

This was honestly the solution for 30 years! A piece has been preserved for posterity in the pavement.

A further landslip in 1984 saw Salthouse Road carried into the river and a temporary wooden track (that bounced and swayed as you drove along it, I remember it well) was installed that lasted until 2014. This is a video of the route.

The award winning stabilisation project at Jackfield

That year a huge project was undertaken to clear the earth down to the bedrock in the most unstable part of the site and drive enormous pylons down into the ground to prevent any further slippage. Thousands of trees were replanted to secure the earth that was replaced. 

To view the area now is to have a glimpse into the last years of the Gorge’s industrial past. Since the mid 20th century, trees have taken back the landscape from its manmade grip and now they mostly obscure any views of the valley. Since the stabilisation project though, as you drive from the Maws Craft Centre towards Jackfield Bridge, you have the marvellous site of the Victorian Gothic style tile factory and church with Ironbridge in the distance.

Well, you can just about see the church here! 

Enjoy it whilst you can. In a few decades the trees will once again reclaim the land. Then it is unlikely we shall ever see a clear view of the valley again in our lifetimes.

Until perhaps the next landslide…