Work for a complete revamping of the Leuvekolk in the Dutch port of Rotterdam has been underway since last year and is expected to be completed in 2020. The Leuvekolk is a spur of the Rotte River, which opens into the Nieuwe Maas in Rotterdam. The objective here is to make this center of Rotterdam greener and thus more attractive as well as more alive. The core of the revamping project is the installation of a new water inlet weighing 30,000 kg to ensure supply of the Leuvekolk with fresh and clean sweet water.
The existing inlet for the sweet water was blocked, which has now been repaired and/or rehabilitated within the scope of the construction measures. In addition, a new sweet-water inlet was installed. This had become necessary since, following deepening of the Nieuwe Waterwegs, in 2018, sea water from the North Sea is increasingly running into the river. With the aid of the sweet-water inlet, the salt-water and the sweet-water content in the Leuvekolk can now be regulated: because, as soon as the salt-water value is too high, the inlet can be opened by remote control and fresh water let in. Plants and animals benefit in particular from the enhanced water quality, but people as well. The new optimized water quality moreover ensures the availability of sweet water for landscape and garden construction as well as for nature along the Rotte, also during dry periods.
Berding Beton produced shaft structure
The installation of a fish passage that enables fish like eel and tricorne to migrate between Rotte and Nieuwe Maas, as well as the design of the river banks under the aspects of leisure and recreation, are also part of the construction project. A docking area for canoes and a spacious sunbathing lawn, for example, are also part of the construction project. The restructuring of the Leuvekolk is financed by the Municipality of Rotterdam, as client, developer and planner; the Port Authority of Rotterdam; the Rijkswaterstaat; and the water authorities of Schieland und Krimpenerwaard. The LIFE fund of the European Community also provides support.
The contract for execution of the works was awarded to the company Henriks Infra B. V., under the leadership of Toine van Poppel. The new water inlet was installed at the site of a former lock. Its crossing was possible thanks to a cover slab. The new water inlet was installed into this cover in the form of a shaft structure five meters high.
The company Bering Beton was awarded the contract for the construction of the new shaft structure. The contact became possible through the Dutch company LBN Betonproducten, which is part of the Berding Beton Group. Raymond Roffel from LBN and Reinhold Siemer from Berding jointly secured the contract.
Bering Beton, a specialist for concrete products in the sector of garden and landscape construction, as well as for road and sewer construction, has ample experience with customized special productions. In this case, apart from demanding requirements placed on the quality of the material, special requests for the optics had to be satisfied. One of these was that the water inlet was to be as inconspicuous as possible to outsiders. To achieve unobtrusive and harmonious blending of the structure into its environment, it was manufactured completely in a dark color.
Large dimensions and special coloring
A one-off special construction of the colored structure in a special black shade required considerable experimenting on the part of the staff of Berding Beton. After some initial difficulties, the task was successfully implemented to the full satisfaction of all parties involved. However, the special coloring was not the only challenge. Due to the dimension of the structure, with a height of 5.5 m and a weight of 30,000 kg, a number of obstacles had to be overcome with regard to logistics. Alone for the transport to the Coolsingel Blaak quarter in the center of Rotterdam, a special permit for the heavy-haul transport usually not permitted there was necessary.
As a result, the water inlet began its journey from Berding Betonwerk, in Steinfeld in the German state of Lower Saxony, initially by heavy-haul transport. In the center of Rotterdam, the structure was then transferred, with the aid of two telecranes, to a special-purpose low-bed trailer with two additional wheels to reduce the axle load. Both the transfer from the unloading place to the erection site as well as unloading there took place in the evening and/or at night, to cause as little disturbance as possible to the residents there. The closed center was reopened for traffic only at 5 o’clock in the morning.
Following successful installation, all parties involved in the project expressed great satisfaction. “That was really an especially challenging task,” summed up Toine van Poppel. “A structure of these dimensions and with special coloring is unprecedented and unique. It was even more satisfying that everything worked so smoothly. The collaboration with Berding Beton was flawless in every way – from sequencing to service to execution. Although the remaining works are still being carried out, upgrading of the Leuvekolk as recreation area has been achieved. That makes us very happy.”