Draining a canal

EVERY NOW AND THEN, a canal needs repairing. For example, it might have sprung a leak either in its retaining walls or in its clay bottom. In such circumstances and no doubt others, the repair work can only be carried out if the canal is emptied of water, a tall order in a canal that might be many miles in length. Recently, we were walking along the towpath of the Macclesfield Canal, which links Marples Lock on the Peak Forest Canal with Hardings Wood Junction on the Trent and Mersey Canal, when we spotted something that we had never noticed before whilst walking along a canal towpath.

What we saw was a pile of sturdy wooden planks, each with two metal handles attached to their narrowest edges. They looked quite modern. We asked a man, who was walking his dog, about the planks. He explained that they were used to block both ends of a section of canal between two consecutive bridges. When these barricades are lined with plastic sheeting, the water between the two barricades can be drained from the part of the canal between the two waterproofed wooden barriers, Then, work can be carried out on the drained stretch of the canal. The planks are known as ‘stop planks’

Our informant pointed out notches carved in the stonework near to a bridge. The notch is opposite another identical one across the canal. It is into these pairs of notches that the planks we had noticed ate inserted to create a dam, I regard myself as being quite observant, but I have never seen or noticed either this kind of notch or the wooden planks for inserting in them during many long walks along canals in other parts of England. Maybe, they are common, but until we walked beside the Macclesfield Canal, I had never seen them before, Maybe, this is because other methods of damming (see: https://www.rchs.org.uk/wp-content/uploads/2017/01/OP-128.pdf) are also employed in addition to that which we spotted on the Macclesfield Canal at Bollington in Cheshire.

The shrinking canal

USUALLY, I LOOK out of the window whenever I am travelling by train. During the 1980s, I often visited London from Kent by train, usually arriving at Victoria Station. The train crosses the River Thames on the Grosvenor Railway Bridge just before it reaches the platforms of Victoria Station. If you are looking out of the left side of the train whilst it is on the bridge, you can spot a building with a curious roof and ornate mansard windows, features that might make you think of nineteenth century Paris (France). For many decades, I have been meaning to investigate this building and today, the 14th of December 2020, whilst walking along the Thames embankment between Chelsea and the Tate Britain, I decided to satisfy my curiosity.

Western Pumping Station

The building with the convex curved roof, which has diagonally shaped tiling, overlapping like fish scales, and mansard windows, is the Western Pumping Station. This sewage pumping station was built in 1875 by William Webster (1819-1888) as part of London’s grand sewage system designed initially by Joseph Bazalgette (1819-1891), which was built mainly between 1865 and 1875. The tall square-based brick chimney next to the pumping station was once an outlet for the steam from the pumps. Now, it serves as a ‘stink pipe’ for exhausting fumes that build up in the sewer. It is 272 feet high. Writing in the 1880s, Edward Walford noted that the pumping station:

“… provides pumping power to lift the sewage and a part of the rainfall contributed by the district, together estimated at 38,000 gallons per minute, a height of eighteen feet in the Low Level Sewer, which extends from Pimlico to the Abbey Mills Pumping Station, near Barking in Essex, The requisite power is obtained from four high-pressure condensing beam-engines of an aggregate of 360-horse power.”

The pumping station and its tall chimney stand between the railway tracks, east of it, and an inlet from the Thames, west of it. A narrow waterway passes from the Thames under Grosvenor Road. Then it moves ‘inland’ via a series of lock gates. This waterway and the dock into which it flows, a watery cul-de-sac surrounded by modern buildings, a rather sterile looking precinct supposed to entice property owners, who want to live in a waterside location, is called ‘Grosvenor Waterside’. The watery appendix sprouting off the Thames is all that remains of the Grosvenor Canal.

The canal was opened in 1824. It was built along the course of a tidal creek that led to a tide mill that pumped water to the Serpentine in Hyde Park and the lake in St James Park. A tide mill works by collecting tide water behind a dam with a sluice, and then allowing the tidal water to escape from it via a watermill as the tide goes out. Modern tidal-barrage electricity generators work that way.

The conversion of the creek to a canal was conceived by Robert Grosvenor (1767-1845), 1st Marquess of Westminster. The short canal, about three quarters of a mile in length, was mainly used for the transportation of coal to the neighbourhood through which it ran. Gradually, the canal was shortened as parts of it were filled in. By 1860, Victoria Station had been built over the Grosvenor Canal Basin.  More of the canal was filled in in about 1899 to build new railways tracks. This halved the remaining length of the canal. In 1925, even more of the waterway was covered over to allow the building of Westminster Council’s Ebury Bridge Estate. What remained of the canal was then used as a dock for loading barges with rubbish. The rump of the canal served this purpose until 1995. Five years later, the construction of the upmarket and rather sterile-looking Grosvenor Waterside housing development, which can bee seen today, began. This includes lock gates, mooring pontoons, and a working swing bridge, but boats are not seen within what remains of the former canal. It is a modern ‘folly’.

Most of the former Grosvenor Canal has disappeared for ever. This is quite unlike many of the so-called ‘Lost Rivers’ of London, which still exist but are hidden from view in underground conduits. One of these, the River Westbourne, flows out of its conduit and into the Thames 270 yards west of the former canal’s entrance, at the southern edge of the Ranelagh Gardens in which Sir Christopher Wren’s magnificent Royal Hospital Chelsea stands.

I hardly ever travel by train to or from Victoria anymore, especially as we now tend to use our car. However, whenever I see the interesting roof of the pumping station and its mansard windows, I remember the days back in the early 1980s when I used to travel between the Medway Towns, where I worked as a dentist, and London, where most of my friends and family resided.