How do people in the past dug channels?

The Netherlands has no less than 6,500 kilometers of canals and channels. A large part of it is already dug long agofor dewatering of peat and polders but also for transport. How did people do that before there were excavators? Doesn't such a half-off channel immediately float full of water?

On the internet you will find A nice animation About how people in the 14th century built the pillars of the Prague Charles Bridge, on the bottom of the Moldau. Before that, they first exposed a piece of river bottom by building a water -retaining shot around it and then pumping the water away with a water wheel. That way they could build the pillar on the dry river bottom. Was it going to dig channels like that?

Jan Verhagen has studied the oldest transport channels in the Netherlands: those of the Romans, dug around the year zero. Verhagen, originally a biology teacher and amateur archaeologist, wrote there A dissertation about (2022, VU Amsterdam).

« Take Corbulo's channel, in South Holland. That has fallen into disuse and silted up relatively quickly, « says Verhagen. « You will find traces of it now, for example of the embankments. Speed ​​traces have also been found in the banks, or kick stitches, from which you can deduce that there is really dug. ”

Then there was Drusus's channel, near Utrecht. There is hardly anything to be found of that. « Drusus crossed the Rhine with his troops at Xanten, but also looked for a sailing route to Northern Germany, » says Verhagen. Sailing over the North Sea was not an option, with the Roman fleet of flat -bottomed bottoms. Drusus therefore had a channel built That the Rhine connected with Lake Flevo and the Wadden Sea. « He probably connected existing Veenmeren, where the Vecht is now running. »

Steel sheet piles

The Drusus Canal became a full branch of the Rhine: a lot of water flowed through. « As a result, it started to broaden and deepen, and also start meandering. All construction tracks have therefore disappeared.  » Verhagen investigated a number of Vechtmeanders between Overmeer and Nigtevecht. « I have been able to prove that those garlands were created in Roman times from points that are more or less on a straight line. »

Writings about how exactly was dug, there are only from the late Middle Ages. « Dry was dug as much as possible, » says Verhagen. « Still, by the way. For the longer channels, a part, also known as a building, was delayed watertight. ” Now we use steel sheet piling, locks were built from the Middle Ages. They also remained in use after the construction, to bridge height differences. « In Roman times they probably used earthen dams, perhaps reinforced with wood. »

A problem with deeply digging is that water is always seeping in your workplace. « You have to get rid of that. Initially that went by hand, with bins. Later there were pump systems, such as a mortaralso known as a water screw, driven by a windmill. « 

Anyway, the monk work must have been, Verhagen emphasizes. « They had no spades of tempered steel, but of wood or wrought iron. They had to remove the ground by hand. And in the meantime, but hurry, sometimes even day and night.  » The work was heavy especially at the bottom of the Geul: there you dug into the most difficult soil layers, and you stood until your knees in the water. « That is where the expression » Outpacking « : you were unlucky if you had to dig at the bottom. »

To share





Mail the editors