Wednesday, 23 May 2018

Return to Three Locks

A second season of excavation has started at the Three Locks Pumping Station, on the Grand Union Canal north of Leighton Buzzard - right on the far north-eastern corner of Buckinghamshire. 

 In 2017 the AAG undertook a 'rescue' dig at the request of the Canal and River Trust because an old canal workshop building beside the canal was scheduled to have a concrete slab poured, to seal off its packed earth and brick floor. What was underneath? Might we find foundations of an earlier pumping house?

Instead we found the footings for twin 20ft boilers, each of which would have been 6ft in diameter. These would have generated high-pressure steam to drive a beam engine to pump water from below the three locks back up to the top. This came as a surprise to the Trust, and the concrete slab failed to appear.

So in March 2018 an AAG team returned for a 'Phase 2', attempting to locate the engine house, which must have been close to both the boiler house and the pump well. After four days and with a trench 4ft deep through layers of spoil we had to admit defeat. Either we were in the wrong place or the engine-house floor was deeper still. But we did identify the base of the boiler-house chimney and the course of its flues from the boilers.

Archaeology or gardening?

Nettles gone, but now there's another problem: bricks!
On Monday 21 May AAG members started work on 'Phase 3', a full excavation of the footings for at least one of the massive boilers. And the day started with a little gardening... Even nettles can tell you something about the archaeology, because they thrive in acidic soil, which in the former Three Locks boiler house is the result of 200 years of industrial history.

... And at the end of the day the spoil heaps from our 2017 excavations were revealed. Now we only have to move those piles of bricks before we can start digging. Watch this space...

No comments:

Post a Comment