Large-scale maintenance at the Kok pumping station
Over the past few weeks, the Rivierenland District Water Board has been working hard on large-scale maintenance to the Kok pumping station in Kinderdijk. “We haven’t found any surprises.”
Built in 1995, the tell-tale pointed shape and glass roof that mark the basin pumping station make it a striking appearance among the buildings of Kinderdijk UNESCO World Heritage. Flanked by its Kinderdijk confrere, the J.U. Smit pumping station, the Kok installation plays a crucial part in the Alblasserwaard area’s water management. “This is where all the basins are discharged”, asserts Albert-Jan van As, maintenance team leader at Riverierenland Water Board. “Nearly all of the water from the entire Alblasserwaard region is expelled at this point.”
During maintenance, its three giant Archimedean screws, each one measuring 4.5 metres across, get a well-deserved glimpse of sunlight after having been under cover for years. The noise-dampening concrete slabs that hide the screws from view when operational had to be removed. The Water Board experts just finished their careful inspection of a range of technical features, including the concrete encasing, the vices themselves, the bearings, and the milling channel. “We haven’t found any surprises so far”, Van As reports. According to Van As, the most recent round of full-scale maintenance performed on the Kok pumping station occurred almost ten years ago. Accordingly, the District Water Board decided it was high time for a thorough inspection in the run-up to the extensive new construction activities throughout the World Heritage site, and in light of the planned expansion of the capacity of the Elshout sluices – which pump out the water into the River Lek – set for the near future.
The Kok pumping station was commissioned by the Alblasserwaard and Vijfheerenlanden District Water Control Board in 1995, replacing the old electric Wisboom pumping station that is presently used as the Kinderdijk visitors centre.
Operating at full capacity, the Kok pumping station is able to pump out a staggering 1.4 million litres of water per minute out of the Overwaard’s Lower Basin. The J.U. Smit pumping station, which mills the Lower Basin of the Nederwaard area, is capable of chucking out well over a million litres of water every sixty seconds. This means that in times of need, these twin powerhouses combined have the power to jettison a mind-boggling 2.4 million litres of water out of the Alblasserwaard every single minute.