Just north of Monnickendam, a new pumping station is built between 2021 and 2023. A building contractor association Pumping Station Monnickendam has been given the assignment by Water Authority Hollands Noorderkwartier to build on this spot. A rather unusual location, right on or under the N247, a busy arterial road between Volendam and Amsterdam.

Plan Rups

The location of the pumping station is in many ways unique. In 1895 August Rups made the first sketches for a ‘boezem’ pumping station at Monnickendam. It was one of four steam pumps intended as a remedy for flooding in North Holland. The total cost of his steam plans was 1.5 million guilders, comparable today to a good 22 million euro. The Water Authority management responsible at the time considered this to be too expensive and plan-Rups disappeared into the bottom drawer. Now, almost 130 years later, the pumping station is coming after all, and engineer Rups has been proved right.

Lock discovery

In October 2021, during building excavations to lay the 7 metres deep foundations for the new pumping station, wood was found. Further excavations with the archaeologist, revealed the underside and walls of a late middle ages sluice. The original lock is about 40 metres long, 6,5 metres wide and 2,5 metres high, and connected the Zuiderzee with the Purmer Ee. The construction of the lock can be described as a wooden, rectangular lock chamber, with an oak floor supporting the heavy oak beamed lock construction.

Little information is available on the history of this ancient lock. There are some indications that the dam was built in the Purmer Ee around 1400, and a sluice was installed in the dam around 1403. What we know now is that the lock from 1567 is around 500 years old. No locks of this size have been discovered before in The Netherlands. This ancient lock has great archaeological and historical value for the history of the Public Works of Waterland and North-Holland.

The lock was not long in service, and was filled up with sand, stones and mud at the end of 1609, bringing about the development of the dam. A new sluice was built about 500 metres away, The Grafelijkheidssluis. This is still in use.

New Pumping Station

In view of climate change this is a logical spot for an extra ‘boezem’ pump, in order to empty any surplus water into the Markermeer. In times of drought it can also let water into the surrounding area. For the fish there is a separate passageway, so that they can swim back and forth. Together with pump stations De Helsdeur at Den Helder, the Zaangemaal and Mantel Gemaal Schardam, water in the area of the Water Authority Hollands Noorderkwartier can be drained off and our feet can be kept dry.