SHIFTING GROUND ON THE GRANTHAM
Restoring Woolsthorpe Locks has been a learning experience, but progress is being made
Restoring the Grantham’s Woolsthorpe Locks has turned into a learning experience, the ground almost literally moving under the volunteers’ feet. But it’s making good progress...
“In the news fairly often – and not all of the news has been good”
That was how we summed up the Grantham Canal’s recent history when we last featured it in early 2012. But we concluded that although it wouldn’t be a quick reopening (is there such a thing?) it seemed that there was “good news in store”, with fingers crossed for a £400,000 Heritage Lottery Fund grant towards the Grantham Canal Society’s programme to restore Woolsthorpe Locks 12 to 15.
So almost four years on, was that optimism well-founded? Well, given that I spent a few days in September as a volunteer laying bricks at Lock 15 during three continuous weeks of Waterway Recovery Group canal camps, it would seem that there has indeed been some progress. Not bricklaying on the lock itself, mind you, but on a brand new weir structure being built adjacent to it.
To understand why, we’ll delve a little deeper (quite literally) into what’s happening at Woolsthorpe, where the news has been a mix of good and not-quite-so-good…
First, the very good news is that the HLF agreed the funding, enabling the lock work to go ahead. And so, after initial clearance and site setup, by summer 2015 it was time for major work to begin on Lock 15.
Given that these locks had been built without overflow bywashes (they relied instead on surplus water overflowing via ‘letterbox’ slots in the brickwork leading into paddle culverts at the top end; and simply overflowing over the gates at the tail end) a bywash was to be built first. It would mean that the lock could be dammed off for restoration without draining the entire canal, and make future maintenance easier. And that was what I was doing: putting up the side walls on a concrete stepped weir, leading down to a pipe culvert buried alongside the chamber.
While that was going on, work had already begun on the lock itself. Prior investigations had shown that the upper parts of the lock walls were leaning inwards, and would need some repair or rebuilding – but the exact extent couldn’t be known for sure until the dismantling began. And this was where things started to go not quite to plan…
Typically on derelict locks, it’s the front surface of the brickwork that’s damaged. The front 1ft or so of the wall might be loose and sagging forwards, but behind it, there is often enough solid brickwork for a repair to be properly tied into.
It didn’t take long for the first week’s camp to discover this wasn’t the case here. Basically, the entire top section of the wall (about 3ft deep and 3ft thick, plus buried buttresses behind it known as ‘counterforts’) had broken away and was slowly falling into the lock. Excavation behind the wall revealed some impressively large cracks.
It got worse. Usually lock walls
increase in thickness to as much as 7ft thick at the bottom. Deeper excavation behind the walls revealed that this one appeared to do the opposite! At the base it was no more than 2ft thick.
The opposite wall was different again: it had iron strapping to reinforce the counterforts, something not seen before.
As GCS Chairman Mike Stone put it, the canal camps’ work was “Three weeks of learning” – and, at the end of it, a major policy shift. Instead of restoration, the walls will be taken right down, in parallel (so as not to put unequal stresses on the ‘invert’ – the curved lock base – which might otherwise “rock like a saucer”) and rebuilt in brick-faced concrete. It won’t necessarily be more work (it might be less), but it’s a major change of plan.
Will Lock 14 be the same? Given that Lock 15 is completely different from Lock 18 (where a wall was rebuilt several years ago), who knows? At any rate, one wall was taken down on safety grounds some years ago by British Waterways, so it will be a complete rebuild, too.
As for 12 and 13, they look to be in much better condition – but a survey later this autumn should find out more. It may well be that each lock was built by a different team, under a different foreman, with (perhaps) a different attitude to cutting corners and skimping. It’s going to be an interesting few years ahead. But Mike’s upbeat about it: “A great learning situation” for the volunteers.
Speaking of which, it’s going to be an almost entirely volunteer project – and much more of a full-time one than most restorations. GCS is putting together teams and leaders for each day – Monday team, Tuesday team and so on – all year, backed up by more WRG summer camps and support from Grantham College.
And it’s not just about restoring four locks: part of the justification for HLF support is the way that the volunteers will acquire skills (whether traditional ones or – say – the ability to operate an excavator to industry standards) which will be transferable elsewhere on the canal and to other restoration projects.
We’ve concentrated on Woolsthorpe Locks, but what of the rest of the canal? While the lock work progresses, GCS volunteers will also be keeping an eye on maintenance of the restored three miles above; other local groups are helping to keep the canal tidy on the final section in Grantham and also at the far end in West Bridgeford; volunteer rangers will keep an eye on each length of the canal, looking for any problems and discussing canal issues with their local community.
And for the longer term? The trickiest part to restore is at the west end, where the original route into Nottingham was lost to road-building in the 1970s and a diversion is proposed. There hasn’t been any physical work, but there’s progress towards the aim of getting the exact line decided and protected in the Local Plan. While the basic route (taking advantage of the Polser Brook) has been identified, planned changes to local roads might provide new opportunities for the canal.
“Something for the long term?” I suggest. Mike is more optimistic. He feels that things could be happening at that end of the canal in no more than a decade, and perhaps substantially less. And for all the progress being made at Woolsthorpe, a link to the national network would do a great deal to confirm that the Grantham is “going somewhere”.
So as I stand back and admire my brick walls climbing up the big concrete steps of the new bywash weir, I can reflect that the Grantham will be taking some more big steps forward in the coming years.
The back of the wall shows some bad cracks
Exposing the second lock wall
Archaeological survey before demolition
Volunteers begin dismantling lock walls
Building a new bywash weir