Today I drove about an hour to get to Lemmer to visit Woudagemaal (“Wouda”), the world’s largest steam-operated pumping station. It was a bleak day – the forecast was zero chance of seeing the sun and ninety five percent chance of experiencing rain. Both limbs of the forecast proved to be true.

It was wet all the way, visibility was poor and the water levels in the canals along the country roads were high. I’m glad I told the GPS to avoid the highways, because without such an acute encounter with the water levels, I might have missed the wonder of the pumping station. Every single day, pumping stations keep the Netherlands from being submerged.

The decision to build Wouda, to solve flooding woes and to reclaim land, was made in 1913. Construction began in 1916. When pumping started in 1920, it was powered by coal which came via ships from the South – and was moved to the boilers on wheelbarrows.

It has enormous capacity: in 1 minute it can drain a football (soccer) pitch flooded with 2 feet of water. For engineers, that’s 4,000 m3 per minute or about 6 million m3 per day

Our tour guide was an older man who loves showing off the pumping station and clearly knows his stuff – the kind of guide I always appreciate and hope one day to be. However his English, though far better than my Dutch, wasn’t up to par. Despite translation help from two other visitors – a young Dutchman and his girlfriend – I may not have got it right.

Until 1967, men (the guide said ‘poor fishermen’) pushed the coal on wheel barrows, across a paved yard, to the boilers; other men shovelled it into the burners. In 1967 the power source was converted to heavy fuel oil, with provision to start and stop with diesel.

The ability to use diesel is essential: you have to start the boilers to heat the heavy oil with steam so that it will flow; then, when you shut down the boilers, you have to ensure the pipes aren’t filled with heavy oil which, after it cools, can’t be moved by a pump.

The pumping station is housed within a dyke. It is equipped with 8 centrifugal pumps driven by 4 steam engines. The engines are driven by superheated steam (320 deg C) and are fitted with 6.5 metre diameter x 6.5 ton flywheels. Perhaps it’s not a coincidence that the normal total operating capacity of the pumps is 65 m3 per second.

The 4 boilers are identical. Of the flame-tube type, each has a diameter of 3.6 metres, a length of 5.3 metres and a heating surface of 220 m2. Two boilers are sufficient to maintain the engines at the optimum speed of 90 r.p.m. A third boiler must be fired if the maximum speed of 105 r.p.m. is required. The fourth boiler is kept on standby, in reserve.

I was impressed by the housings of the centrifugal pumps. I thought I saw a flash of appreciation on the guide’s face when I asked about them. If I understand correctly, the housings are made of sections fabricated from thick sheet steel in Utrecht and assembled and riveted together on site. I couldn’t tell how the impellers were fabricated.

I was also impressed by the gantry which can lift up to 9.2 tons. It has no I-beam. It’s still not electrically powered, either for horizontal or for vertical movement.

The red brick chimney has a diameter of 6.25 metres at the bottom and tapers to 3.0 metres at the top, 55 up.

The inlets to the pumps have strainers made of teak wood from Indonesia.

The pumps are operated 3 times a year: twice for the benefit of students and visitors and a third time, typically in February, to prevent Friesland from flooding.

The station is managed by the Friesland water authority. When needed, they just call in staff – who drop whatever else they are doing and come to the station to run it. Must be the highlight of the year for them – I know it would be for me.

In 1998 the Woulda pumping station was ‘inscribed’ on the UNESCO World Heritage List (# 867) for the following reasons:

Criterion i: The advent of steam as a source of energy provided the Dutch engineers with a powerful tool in their millennial task of water management, and the Wouda installation is the largest of its type ever built.

Criterion ii: The Woulda pumping station represents the apogee of Dutch hydraulic engineering, which has provided the models and set the standards for the whole world for centuries.

Criterion iv: The Woulda pumping installations bear exceptional witness to the power of steam in controlling the forces of nature, especially as applied to water handling by Dutch engineers.

After visiting Woulda I have a better appreciation of the dependence of the Dutch on mastery of water engineering – not just the technology, but also the administration of it.

Wouda is a living example of the estimated 700 steam powered pumping stations which kept the feet of the Dutch from getting wet from 1900 to 1910.

Wouda is not only the largest steam powered pumping station ever built. It is also in mint condition and still up to the task.

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I wrote about my visit on my blog at write2rest.blogspot.com