Project characteristics
A river’s water naturally carries stones and sand with it and deposits these downstream. Increasingly smaller amounts of sand and gravel are entering Dutch rivers, in part due to human interventions such as narrowing, straightening and extraction of raw materials. This is one factor that serves to increase flow speed and thus erosion. Causing river beds and water levels to sink. At low water this makes things difficult for shipping and dries out the flood plains.
Pilot
Rijkswaterstaat PPM (Programmes, Projects and Maintenance) is running a pilot, for the purposes of which Martens en Van Oord is doing the work. A layer of gravel and sand 30 centimetres thick will be deposited evenly in the Upper Rhine, just over the border at Lobith. This is called sediment replenishment.
The sand and earth will distribute itself naturally and fill the deep sections in the river. This will raise the water level in the shallow sections and render the river more readily navigable.
70,000 m3 gravel
This pertains to the second phase of a pilot, with the first phase having been implemented in 2016. The work encompasses the supply and depositing of 70,000 m3 of gravel into the Upper Rhine. The use of split barges, which will bring the material in by water, will minimize nuisance to shipping traffic.
The work is to be performed between April and October 2019.
Keen to find out more about sediment replenishment? Watch this film from Rijkswaterstaat.
