ALL HANDS TO THE PUMPS

Sometimes, the local geography dictated that canals needed to be equipped with pumping stations to keep them from running dry. Now, 200 years on, we look at how today’s engineers are keeping the successors to those pumps working

In an ideal world, canals wouldn’t need pumps to supply their water – and many don’t. Provided with adequate reservoirs, often tucked away high in the hills some miles away, they can draw on enough supplies by gravity alone to see them through a typical summer, before the winter rains replenish their stocks.

Other canals are less well-equipped with supplies which over the years, as the canals got busier, needed to be supplemented with back-pumping schemes, returning water used by lock operation back up to the summit level for re-use. In recent years, the revival of the canals for leisure led to several of these systems being reinstated or new ones installed, for example enabling water to be pumped all the way east up the Kennet & Avon from Bath to the summit at Wootton Rivers, or right through from the Black Country to the southern Grand Union.

But there’s another possible reason for canal water supplies to need pumping – and not just in dry summers when it runs short. Occasionally, the local geography meant that it wasn’t possible to find water supplies (or to find suitable sites for reservoirs to store the water) sufficiently high up to feed the canal’s highest levels. There might be no alternative but to site the reservoirs at a level where water would need to be routinely pumped out of them and up into the canal.