PRORIL submersible dewatering pump for the construction of the Nieuwpoort storm surge barrier

In Nieuwpoort - on the Flemish coast at the mouth of the Yser - work is currently underway on a major hydraulic engineering project. In a few years' time, a unique dam will regulate the influx of seawater into the Yser River and ensure that the hinterland remains dry in the event of a storm surge. The cofferdam is almost watertight, making it "easy" to pump the seepage water away using a PRORIL Tank submersible pump, while vessels sail close by.

A unique dam
There are just two similar rotating dams of this kind in Europe. Building such a project is therefore not an easy task. Like all dams, the central challenge is the protection against water. However, the North Sea cannot be contained without a struggle and certainly does not make things easy for builders.

When the project is finished, an immense rotating steel barrier between two abutments will ensure that predicted storm surges are kept at bay. The dam rotates 90 degrees and can thus, in order to protect the Belgian coastal area, close the entire channel in a short period of time. For maintenance work, it is even possible to turn the barrier to a 180-degree position.

“Easily” pump out seepage water
A year ago, the first step in the project was taken with the construction of a gigantic 22-metre deep cofferdam on the left bank of the Yser river. The concrete foundation has now been poured and the 60-metre-long and 16-metre-wide steel walls and seals keep the surrounding water under control. In order to pump out a minimum amount of seepage water, PRORIL distributor Rental Pumps Belgium BVBA has supplied a 3.7 kW strong construction pump: type Tank 337.

Pumping away water is easier said than done. The PRORIL Tank 337 delivers up to 50 m3/hour and pumps water up to a height of 28 metres over the edge of the cofferdam. The main reasons for opting for the PRORIL construction pump are its dry-running resistance and the ease with which the pump pumps a mixture of air and water.

Working safely while vessels navigate close to the cofferdam
During construction of the storm surge barrier, the navigation channel will remain open to shipping. To guarantee the safety of the people at the bottom of the cofferdam, the steel walls have been reinforced against external impact. The cofferdam can 'absorb' a collision of a vessel moving up to a maximum speed of 8 knots.

PRORIL Pumps Europe is proud that its product has been used in such an important project and is confident that the pumps will function satisfactorily.