The Nederrijn and Lek weir combination consists of a series of 3 weir complexes in the Nederrijn and Lek rivers. The weirs are located at Hagestein, Amerongen and Driel, and play an important role in the river water management programme undertaken by Rijkswaterstaat. The weir at Driel distributes river water across the Nederrijn, Lek and IJssel rivers. As a result, sufficient water is allowed to flow to the IJsselmeer. Together, the 3 weir complexes ensure that water levels remain sufficiently high for rapid and safe ship movements on the rivers. The various weirs have now been in use for 50 years, and are due for large-scale renovation. Rijkswaterstaat has awarded the renovation project to Siemens Nederland.
The eye-catchers in the complex are the huge steel arches, known as visor gates. Sweco is responsible for the design and engineering of the temporary retainer systems that will be used to stem the water flow during the replacement of the steel visor gates. We are also responsible for the design and engineering of the new visor gates and will provide the design and engineering for the soil protection measures around the complex. These measures are essential to prevent erosion of the river bed during the renovation work. By replacing the structures, technical installations and moving parts, these weir complexes will be able to continue to fulfil their essential task safely and reliably, now and in the future.
INTEGRATED DESIGN ENVIRONMENT
Sweco has placed the various sub designs in a single integrated design environment, together with BIM. This process helped reveal the various interfaces between the sub designs. Within the design environment, the new visor gates and the temporary retention system were designed using a fully parametric 3D method. The land abutments, the weir uprights and the new poured concrete elements, including the reinforcing steel, were all fully 3D modelled. Sweco supplied an integrated design according to which clear and efficient design and construction choices could be made in the implementation phase. As a result, Rijkswaterstaat will be able to make cost-effective maintenance choices, in the maintenance phase.