LIGHT AT THE END OF THE TUNNEL?
We take a short boat trip into the Chesterfield Canal’s very long and very derelict Norwood Tunnel – and look at the Canal Trust’s cunning plans for reopening it
The Chesterfield Canal Trust’s cunning plans for reopening the derelict Norwood Tunnel
Looking into the rather forbidding hole that was once the entrance to one of the longest canal tunnels in the country, I can’t help comparing this trip into the Chesterfield Canal’s Norwood Tunnel with a similar trip into Sapperton Tunnel on the Cotswold Canals a few years ago.
Both long-abandoned tunnels; both seriously damaged by roof falls over the decades that they had been shut; but both subject to reopening plans by well-established and active canal restoration societies for whom these derelict holes will eventually form important links in navigable waterways.
In the case of Norwood, it’s the vital link between the navigable eastern 32 miles from the Trent via Worksop to Kiveton Park, and the western sections including the current focus of restoration attention (and of the campaign to save it from the HS2 railway) from Killamarsh to Staveley – and the isolated restored final length from there to Chesterfield.
But in other ways the tunnels are very different – and one way is immediately obvious. As we clamber through a small opening that has been broken out of the bricked-up eastern entrance to Norwood, I can’t help thinking that, compared to Sapperton’s grandiose eastern portal, this seems a bit of a rat-hole. Built for single-file narrowboats, its dimensions were tight at the best of times – and sometimes even tighter, as I’ll explain.
Clambering into a small electricpowered open boat, we set off into the tunnel, dodging some surprisingly long
straw-like stalactites dangling from the arch. The gloom is broken by a bright inspection lamp shone by a Canal & River Trust engineer that I’m sharing the boat with – and that’s the reason for this trip. Despite not seeing a boat since 1907, Norwood is still CRT’s responsibility, and is checked at ten-yearly intervals to make sure it isn’t going to collapse and cause problems for properties above.
At a first glance, the narrow brick bore looks in remarkably good condition for its age – but, in fact, this section was rebuilt not long before it closed. And after a quarter-mile or so, our journey comes to an end as a few yards ahead of us we can see silt rising above water level (and the remains of what might have been an abandoned inspection boat – I bet that was a fun trip!)
What we’re seeing is the start of a large quantity of soil that has fallen through the collapsed roof of the next section. This marks the end of the length that CRT checks – and that the Chesterfield Canal Trust hopes to restore. And while for CRT this is a routine engineering inspection, CCT sees it very much as an opportunity to get some first-hand knowledge with a view to the future.
So why doesn’t CCT intend to restore the remaining mile-and-a-half? And what does it plan to do instead? The answers relate to the area’s history of coal-mining, and to the tunnel’s unusual construction.
Returning to our earlier comparison, unlike Sapperton which passes under farmland, Norwood ran through a major colliery site, with coal extracted from four different seams under the tunnel. This led inevitably to subsidence. At times the headroom was reduced to barely 4ft in places, and stockpiles of sand were kept by each portal to allow
unladen craft to be ballasted down so that they would fit through at all.
Constant rebuilding and repair of collapses continued until 1907, when the canal’s owners gave up. The tunnel was abandoned, and although a little local traffic continued, this was the beginning of the end for the canal west of Worksop.
Since then there have been further collapses, parts of the tunnel were infilled by the National Coal Board where it passed under the mine, and a length was filled with concrete when the new M1 motorway crossed it in the 1960s.
By the time coal mining finished and CCT commissioned consultants to study the possibilities for reopening, restoring the old tunnel wasn’t really an option. Nor was building a new tunnel, given the state of the ground after 200 years of mining. A third idea of using a nearby disused railway tunnel was also dismissed because it was on a slope that would have made things too tricky.
But returning once again to our comparison, unlike Sapperton which dives deep under the hills, Norwood isn’t very far underground at all – barely 12ft of cover for much of the way. Indeed, at the time of construction, an alternative plan would have seen a shorter tunnel at a slightly higher level. (Landowner opposition may have prevented this.)
That shallow depth exacerbated the tunnel’s problems (for example, its treatment by the M1’s builders) but it also looks like being its saving grace. It allowed the consultants to come up with a fourth, much more practicable, option: partial reopening of the tunnel combined with building a new surface-level route to bypass the rest. Even better, land reclamation of the former colliery and its tip have already done some of the work.
That ‘partial reopening’ means restoring the quarter-mile that the engineers and myself have just looked at. And beyond there? Well, returning to the entrance and emerging blinking into the daylight, I head along the start of the old tunnel-top horse path to see for myself where the plans for bypassing the remaining length of the tunnel will lead.
Soon the path crosses Hard Lane – and unfortunately, the first tunnel collapse is just before this point. So that means that when the collapsed section of tunnel is dug out to create an open cutting, a new bridge will be needed immediately to carry the lane over it. But it gets better…
Just across the lane, a new set of three staircase locks will raise the canal to ground level, at a point where several sizeable ponds known as Kiveton Waters are in use for fishing. Built as part of the colliery reclamation with a view to being turned into a marina when the canal gets here, they are already owned by CRT.
Skirting the south side of the ponds, the new canal then takes a gentle S-bend to the right of the colliery tip site, along a reserved route through parkland criss-crossed by paths and cycleways. Some initial earthworks in preparation for the canal channel have already been
‘Restoring the old tunnel wasn’t an option. Nor was building a new one, given the state of the ground after 200 years of mining’
These straw-like stalactites have grown since the last inspection a decade ago
The ten-yearly inspection finds that the first quarter-mile is in good condition
The bricked-up eastern portal has been opened up ready for inspection
Kiveton Waters: a fishery today, but designed as a marina for the future
The former west portal will be bypassed, as only a few yards of tunnel survive here
The canal diversion will follow this footpath past the former colliery tip
This bridge will take the canal under the M1