There’s something strangely miraculous about using water to lift water.
It’s not by any means unusual. Even before the Industrial Revolution, in mines particularly, waterwheels were used to harness the power to lift water vertically, using Heath Robinson contrivances called “rag and chain” pumps.
The engineer George Sorocold (c1668-c1738) used waterwheels to provide mains water to houses, first in Derby, and then elsewhere including the area around London Bridge.
Just about the only surviving example, however, is at the Claverton Pumping Station on the Kennet & Avon Canal, a few miles outside Bath.
The Kennet & Avon notoriously suffered water-supply problems, primarily because its summit level was so short, but also because the stretch along the Avon valley around Limpley Stoke was continually drained by the Bath locks and also leaked like a sieve.
The Claverton pump uses two adjacent breastshot waterwheels, each seventeen feet in diameter, to lift water fifty gallons at a time 48 feet from the River Avon into the canal.
It’s an oddly peaceful piece of machinery. The wheelhouse has all the illusory ease of water-power. It’s easy to forget the amount of energy concealed in the tranquil water and the idle splashing of the wheel paddles.
The water drives what is in effect a beam engine, very like the more familiar stationary steam engine, but at Claverton there’s no heat, no sense of simmering energy. It’s extraordinarily restful to watch the beam rise and fall without apparent effort.
The pump started work in 1813, and stopped finally when an obstruction stripped many of the oak teeth from the main spur wheel in 1952. The canal was no longer navigable by that time and the British Transport Commission chose to replace it with a diesel pump simply to fulfill their legal obligation to maintain a level of water.
Fortunately, industrial archaeologists were alert to the significance of the place, and the Kennet & Avon Canal Trust, assisted by the then Bath University of Technology and apprentices from the British Aircraft Corporation at Filton, Bristol, painstakingly restored it.
The water was heaved from the river into the canal once more in 1976.
Now it’s possible to enjoy the sights and sounds of eighteenth-century engineering on regular opening days. The team-members at Claverton are very welcoming: they have an excellent coffee machine and an executive loo.
The best access is by walking along the towpath. Arriving by car involves dodgy parking and an unnerving crossing of the Wessex Main Line railway.
Details of opening times and operating days for the Claverton Pump are at http://www.claverton.org.
The 72-page, A4 handbook for the 2012 Waterways and Railways between Thames and Severn tour, with text, photographs, maps and a reading list, is available for purchase, price £15.00 including postage and packing. To view sample pages click here. Please send a cheque, payable to Mike Higginbottom, to 63 Vivian Road, Sheffield, S5 6WJ.