Cycling Belgium's Waterways: History of the Charleroi Canal

THE BRUSSELS - CHARLEROI CANAL
a history

INTRODUCTION

The construction of the Brussels - Charleroi canal started in 1827, and the canal became operational in 1832. The main purpose was the transport of coal from the mines in the Charleroi region to the north of the country. A second argument was to connect the Walloon industry region with the harbour of Antwerp in Flanders. Brussels was already connected by good waterways with Antwerp. Before the construction of the canal the industrial production could only be transported via France, or over the Sambre and the Meuse rivers with a large detour over Holland. The canal, from the first 70 tons version over the upgrades to 300 and 1350 tons, has been characterized by some unusual construction. To understand the reasons of the existence of these structures (two tunnels and the modern incline at Ronquières), it is important to realise that Brussels is in the basin of the river Schelde, and Charleroi in the basin of the river Meuse. This means that the country between these two cities there is a ridge has to be crossed. Brussels is at about 25m above Sea level, Charleroi at about 100m and the divide at 135m.

THE 70 TON CANAL

The construction of the canal was not a problem between Brussels and Ittre, but south of Ittre the landscape becomes very hilly and the underground rocky. The result was a canal with a very curvy trajectory with sharp turns, and a large number of locks. The most difficult section was between Ronquières and the watershed just south of Seneffe.

Between these two villages, the canal had to follow the very narrow valley of the Samme river to rise from 50m above sea level at Ronquières to 120m at Seneffe. The canal was only 6m wide at the water surface and 3.2 at the bottom. It was 2m deep. These dimensions had direct effects on the maximum size of the boats. Therefore a new type of river boat was designed. It was called the "sabot", the French word for a wooden shoe. They were 22m long, 2m wide and 1.8m deep when fully loaded. The capacity of these boats was about 70 tons. Between Ronquières and Seneffe about 30 locks were needed, since the locks could only bridge 2 to 2.5 meter. The total number of locks between Brussels and Charleroi was 55. A section between two locks is called a "bief". Some"biefs" were only a few hundred meter long. It took 3 to 4 days for a boat to be towed from Charleroi to Brussels. Manpower, and later horses were used.

The biggest problem was crossing the ridge south of Seneffe. Seneffe is at 120m, but the country then rises suddenly to 135m over about 2 km and then goes down again. Various possibilities were considered to avoid 10 to 15 additional locks over a distance of 2 or 3 km, not only for the loss of time, but also for the fact that a lock uses a lot of water. Every time a lock is used, a quantity of water flows from the upper part to the lower part, and this is especially a problem on the 'roof' of a watershed, because that section has two adjacent sections which are lower. Some ideas were: simply not connecting the two sides of the canal and unloading the boats, or towing the boats over a railway system to cross the bump in the landscape… Finally, it was decided to construct a tunnel. The first tunnel was called "Tunnel de la Bête Refaite" and was 1300m long, just wide enough to contain a boat and a tow path. The underwater cross section was 8 square meter. Of course, in those years, no light was provided.

UP TO 300 TONS

From 1841 on, some sections of the canal were upgraded to 300-ton boats. These boats were twice as long and twice as wide as the old sabots. The upgrade was finished in 1882 over the full length of the canal. The total number of locks was reduced to 38. The upgraded canal was simply a widened version of the first canal, following the same trajectory, with one exception: the tunnel. The first tunnel, having two feet thick brick walls, could not be widened and therefore a new one just a few hundred meters north of the first one was constructed. This is the "Tunnel de Godarville" which is still present, although not operational anymore. This second tunnel is about 8m wide and also contains a tow path over its full length of about 1km. It is possible to enter the tunnel (at your own risk) at the north-west exit near Seneffe, but it is not safe to go more than a few meters, because the tow path is in bad condition since the tunnel has not been used and maintained since 1970. At the other exit, the old canal has been filled up. This exit is difficult to find. The tunnel had iron doors which were closed in the winter to avoid damage of the brick walls when cold wind was blowing right on the entrance. Guard locks near the exits were provided so that the tunnel could be drained for maintenance without having to drain the whole "bief". This would have been a too large loss of water.

THE 1350 TON CANAL

In the 1920s the canal section between Brussels and the steel factories of Clabecq was upgraded to 600 tons, with locks capable to handle 1350 tons in case future upgrades were needed.

After the Second World War, it was decided to upgrade the canal to 1350 ton over its full length. This was done mostly be widening the canal to about 30m, and be rectifying as many curves as possible. With modern machines it was now possible to cut through the rocky hills in the vicinity of Ittre. The number of locks was also greatly reduced, with a lock of 14m level difference at Ittre. Wide basins at both sides of this lock are needed to avoid strong currents when the lock is filled or emptied.

Once again the big problems were the section between Ronquières and the crest, and how to cross the crest. It was not possible to fit a 30m wide canal in the narrow and curvy Samme valley. Also, the physical dimensions of a 1350 ton boat are a maximum length of 80m, and 10m wide. So a new section with a new trajectory was needed.

First, a decision had to be made how to cross the 70 meter difference between Ronquières and Seneffe. By 4 or 5 super locks like the one in Ittre ? The problem is that such a lock uses an enormous amount of water: 12,000 cubic meter each cycle.

However, just south of Ronquières the landscape rises to 110m over a distance of less than one kilometer. If it were possible to climb this hill with a 1350 ton boat, the boat would virtually be at the Seneffe level immediately. It was therefore decided to construct the incline of Ronquières: not an real elevator like the new 73m elevator in Strépy at the Canal du Centre, but a system with two large steel water containers, just larger than the boat they contain. Each container rolls on its 236 steel wheels over a four track railway up or down the 1.4 km long 5° incline. When the container goes up, a counter weight comes down or vice versa. The speed is only a few km/h, and a pedestrian can easily walk faster. The two containers operate independently of each other since each one has its own counter weight. At the top, the canal is about 10m above the surrounding landscape, and lies on bridge and then a wide dike until the landscape comes at the same level after a few kilometres.

Second, what about the tunnels at the crest? A third tunnel, which would have been at least 15 or 20m wide to handle 80m long and 10m wide ships, was not an option since it was now possible with modern digging machines to simply cut through the watershed. The cut is about 25m deep and was made more or less at the position of the first tunnel, so very little is left of this tunnel: only a small section which is now used as a bat cave, and which is therefore not accessible. One end is visible in the south side of the incision just south of the road bridge crossing it halfway. The total number of locks on the 1350 ton canal is only ten, plus the incline at Ronquières. A boat can now travel from Brussels to Charleroi in one day. The tow path is in excellent condition along the modern canal and greatly appreciated by bicycle amateurs. But the nicest trajectory to explore is certainly the old section between Ronquières and the second tunnel, with its many curves, its narrow valley in the vicinity of Arquennes and the 15 locks which are now transformed in waterfalls. Ronquières is a good starting point to ride along the old canal to the watershed, take a look at the tunnel, go back along the new canal and come down along the incline. This is a loop of 35 km. Look at Dan Gamber's bicycle site for maps, and don't forget to taste one the more then 300 Belgian beers when you are back in Ronquières. For obvious reasons it is best to drink these beers after the trip.

by Paul Hellings, June 2002

More information can be found on the Internet, but since the most interesting part of the canal is the French speaking part of Belgium, most of the sites are in French. A lot of information was collected by Marcel Franssens, a civil engineer of Halle (Belgium). He wrote a brochure about the history of some Belgian waterways. This brochure is in Dutch.

Last updated 1 August 2002