Keeping weirs suitable for transit

Abstract

The weirs in the Meuse river in the Netherlands are after 100 years end of technical lifetime. As a consequence, Rijkswaterstaat is planning renovation or complete replacement. The present weir openings of 60 m wide are used for transit of vessels at high river discharges, when the weirs are lowered. Based on agreements between Belgium and the Netherlands from 1839 [1] and 1843 [2], the possibility of sailing through the weirs during high river discharges should remain (principle of non-deterioration). For the case of replacement, Rijkswaterstaat had a preference for a weir with three openings, for reasons of maintenance and water management. The Dutch MARIN institute executed fast time- and real time simulations to get insight in the navigability of a weir, with openings of 38, 38 and 24 m wide. Results were also used for improvement of the Dutch Guidelines for waterways 2020 [3]. The weir at Sambeek was taken as representative for the other Dutch weirs in the Meuse; 3D flow charts were delivered by the Dutch Deltares institute. The MARIN research showed, that the configuration studied was not feasible; recommended was a middle weir opening of at least around 50 m wide, corresponding with the swept path approaching the weir of 36 m plus ½B at both sides.