Hölscher Projects
Floodgate Hooksiel
For the refurbishment of the Hooksiel lock, Hölscher installed a temporary pumping station to drain the Hooksmeer. During the several months of construction work on the lock system, the lock chamber was dewatered and a redundant pumping system was installed to regulate the water level reliably and ensure drainage towards the North Sea.
High-capacity pumping station right on the North Sea coast
The Hooksiel lock connects the Hooksiel inland waterway, known as the Hooksmeer, with the North Sea and plays an important role in protecting the region against flooding. As part of refurbishment works on the lock system, the lock chamber first had to be dewatered to allow the repairs to be carried out.
As regular drainage via the lock is not possible during the construction phase from October to April, Hölscher installed a temporary pumping station. This enables the water level in the Hooksmeer to be controlled and excess water to be discharged reliably.
Our services
Dewatering of the lock chamber
At the start of the project, the lock chamber was drained to allow construction work on the lock system to take place. Residual water entering via the lock gates is collected in pump sumps and continuously pumped out.
Construction of a temporary pumping station
As regular drainage via the sluice gate is not possible during the construction period, Hölscher installed a temporary pumping station to regulate the water level in the Hooksmeer. The pumps are activated automatically as soon as a defined water level is reached, ensuring that the water is discharged in a controlled manner.
Ensuring transport infrastructure
To discharge the water, around 200 metres of DN250 pressure pipes were laid for each pump. To cross the dyke road, the subcontractor HJA constructed an asphalt ramp over the pipes, ensuring that the road remains fully accessible to cars, lorries and cyclists.
Technologies used
Frequency-controlled pump technology
The temporary pumping station consists of two frequency-controlled pumps, each with a flow rate of up to 900 m³/h. Thanks to the automatic control system, the pumps adapt flexibly to the current water level in the Hooksmeer.
Redundant pump system
The system has been designed with redundancy to ensure a high level of operational reliability. Should the main pump fail, the second pump automatically takes over.