Monnickendam pumping station

Schermer basin

The Monnickendam pumping station does not drain a polder, but a reservoir, known as the Schermerboezem. This is a storage area consisting of (ring) canals and channels into which the polders pump their excess water. From the reservoir, that water is ultimately discharged into the sea. The Schermerboezem was initially very large. However, due to the reclamation of the Beemstermeer, the Wijde Wormer, Purmermeer, Schermeer, and Starnmeer at the beginning of the^17th century, little 'space for water' remained. This occasionally caused major problems in winter. When storms and high tides prevented water from being discharged into the sea, the drainage channels and canals quickly became full to the brim. Polders with low embankments were then doomed. The drainage water overflowed and they were flooded.

Rups' steam plan

Steam drainage became available in the^mid-19th century. From 1866 onwards, the board of the Schermerboezem administrator, the Hoogheemraadschap van de Uitwaterende Sluizen (Water Board of the Drainage Locks), continuously discussed the construction of steam pumping stations to pump the water from the reservoir into the Zuiderzee. However, this did not happen, partly due to the enormous costs involved and the fact that things were often just about working.

After a few wet years, August Rups, engineer at Uitwaterende Sluizen, developed a new large-scale steam plan in 1895-1896. He proposed the construction of four pumping stations in the Zaan region along the North Sea Canal and near Den Helder, Schardam, and Monnickendam along the Zuiderzee coast. Rups estimated the costs at one and a half million guilders, comparable to 23 million euros today. The board balked at this, and the Rups plan disappeared into a drawer.

Still ground

It was not until after 1960 that the tide turned. Agriculture became more demanding, and the fight against water pollution and salinization made drainage of the reservoir truly necessary. With the help of pumping stations, the reservoir could be thoroughly flushed with fresh water from the IJsselmeer. In 1966, the Zaangemaal pumping station in Zaandam became operational, followed in 1972 by a second pumping station, De Helsdeur, near Den Helder. Climate change played an important role in the decision by the current Hollands Noorderkwartier Water Board to build two more pumping stations. In 2017, the Cees Mantel pumping station near Lutje Schardam was put into operation, followed by the Monnickendam pumping station in November 2023. This completes the old Plan Rups after more than 125 years. After all, he had already proposed the construction of pumping stations in the Zaan region and near Den Helder, Schardam, and Monnickendam in 1896.

Lock in the construction pit

The Monnickendam pumping station is located in Nieuwendam. This dam was built in 1401 to separate Lake Purmermeer from the Zuiderzee. The dam contained a lock for shipping and drainage. However, the exact location of this lock in the metre dam was unknown. During the construction of the new pumping station in November 2021, the contractor came across heavy beams and planks. These turned out to be from a wooden lock more than thirty metre and over six metre .

Of course, the discovery led to extensive archaeological and historical research. The latter investigation of old archives revealed that the first lock, dating from 1401, had been closed in 1534. The city of Monnickendam then built a new lock in the Nieuwendam in 1565-1567. That was the focus of the construction site. No remains of an even older predecessor were found under this second lock. It is therefore possible that remains of the first lock from 1401 are still present elsewhere in the dam.

The lock, built between 1565 and 1567, remained in service until the end of 1609. It was then closed due to serious dilapidation. Two years later, construction began on lock number three at yet another location, just north of Monnickendam. This lock, known as the Grafelijkheidssluis, is built of brick. It is still heavily used by recreational boats.