Friday, 18 September 2009

Cromford Canal - Butterley Tunnel

Butterley Tunnel
Cromford Canal

You could say that this blog post is utterly Butterley, as it is entirely devoted to this 1 3/4 mile subterranean waterway route.

My towpath treck has now taken me from Cromford all the way through Ambergate and I now find myself, quite literally, at a watershed. It is a small miracle that William Jessop managed to maintain a level lockless pound for so many miles through very hilly country, but at Butterley his contour options ran out.

For Butterley Tunnel (originally known as Ripley Tunnel) coal was both its greatest triumph and ultimately the cause of its downfall. When originally constructed in 1794 it was the third longest canal tunnel in England, with its 2966 yards coming in just behind the Sapperton and Dudley. This makes it one of the earliest long tunnels and given its pioneering nature, it was built to small dimensions - a mere 9ft wide at the waterline.

Whilst this tunnel allowed the Cromford Canal to maintain its level course all the way to Pinxton, it also provided direct access to Butterley Carr Pit, for which an underground wharf was built approx 880 yards in from its western portal. The tunnel was constructed with 33 vertical access shafts, the deepest of which was an impressive 210 feet and, just to make things interesting, the tunnel was made to pass right under its own 50 acre reservoir on the hill above.

All went well for nearly 100 years, with the canal flourishing, even coping with the introduction of the railways. The tunnel itself had to evolve with the new railways, with a further 117 yard extension added to the western end to carry the tracks above. However, the tunnel's uneasy relationship coal mining finally caught up with it and the resulting subsidence triggered a series of collapses. The first was in 1889, which took 4 years to repair, only to collapse again in 1900. This time an Act of Parliament was needed to raise the funds to effect a repair and when a third collapse occurred in 1907, before the second repair had started, the canal was abandoned to its fate.

So it's now over 100 years since a craft navigated it's narrow channel, and about thirty years since an internal inspection was carried out by a team of intrepid souls. This group penetrated 1100 yards in from the west, before being halted by an increasingly unstable arch. This 1970's expedition yielded some fascinating photos which can be found on the Friends of Cromford Canal website.

With only 1/3rd of the bore explored in living memory, no one knows what state it really is in. The good news is that mining has long since ceased and and further subsidence is unlikely. Having said that, I am sure that repairs to allow a return of craft will be expensive.

The road to full reinstatement of this tunnel may be some way off, but with progress being made to push forward from Langley Mill on the Erewash to Pinxton, the Butterley Tunnel will be the next big obstacle to be overcome.

For the time being we will have to content ourselves with a glimpse of each end, a handful of internal photos and a stiff walk over the hill above.

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