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Word of the Day: sluis (lock, sluice)

What a wonderful day for the FIETS (cycle) this was! This morning I cycled from Voorburg (where I live) to old Leidschendam because I wanted to take a photo of today’s subject: the SLUIS (lock). When I arrived at the centre of the village, there was a very long line of cars along the Damlaan and the Damplein. Some people stood outside their cars complaining and wondering why they had to wait so long. How happy I was that I could continue on my bicycle to the lock. When I arrived, I immediately understood the reason for the traffic jam.


A long and broad barge by name of ‘Bona Spes’ (Latin for ‘good hope’) from Gouda was slowly edging its way through the narrowest of locks in the direction of Delft. After a long while it had freed itself from the gate and sailed full speed ahead. The people on the terraces returned to their coffees with APPELGEBAK. This kind of spectacle occurs very frequently, but the Dutch will never get used to it, whether they’re watching or waiting.

The Netherlands is a land full of SLUIZEN (locks) and BRUGGEN (bridges), KANALEN (canals) and RIVIEREN (rivers). The waterways form an impressive network of about 5,000 kilometres in total. They have two main functions. One is for traffic over water. This function has many advantages but the environmental one is exceptional. Waterborne transport has the least impact on the environment due to its lower energy consumption per tonne kilometre. This ensures a CO2 emission that is three times lower than road transport.

As you probably know, over half of the western and northern parts of the Netherlands lie at or below mean sea level. The lowest point, east of Rotterdam, is almost seven metres below mean sea level. If all the pumping stations stopped working and if there were no dikes and dunes in this country, more than 65% of the country would be flooded at high sea and high river levels. The Dutch coast line would be situated in Brabant and Gelderland. Amersfoort would be a seaside resort.

So you must have guessed what the second function of the waterways is by now: drainage. Because so much land is below mean sea level, millions of litres of water must be drained every minute of the day. Pumping engines and sluices work night and day to perform this feat.

A SLUIS is both a lock for barges and a sluice for drainage. The English word ‘sluice’ and the Dutch SLUIS both come from Old Dutch slūsa which means ‘weir’ or ‘dam’. The oldest occurrence as the Latinised place-name Slusis dates from 1139, This is the village ‘Sluizen’ in the Belgian province of Limburg. The word may sound very Dutch and, sure, it did travel all around the world with our engineering consultants and watermanagers, but originally it is the Latin word ‘exclusa’ (closed off) which comes from ‘exclūdere’ (to close off or out). The ensuing word ‘esclusa’ moved via Medieval French to Dutch. And now all of the Netherlands is riddled with SLUIZEN.