Opportunity
The Netherlands sit at the downstream end of the major river catchments of Rhine and Meuse Rivers, which are prone to high discharges during winter periods that lead to high water levels in Dutch rivers.
The area available for Dutch rivers has decreased during the past centuries. The rivers are confined by increasingly higher dikes and land is gradually subsiding. Rivers are expected to discharge an increasing volume of water due to climate change.
Solution
Convinced that a totally new approach must be applied to river management, the Dutch government developed "Room for the River," a program implemented by the Ministry of Infrastructure and Environment. The program also invested in environmental quality by increasing natural and recreational values of the rivers region.
Mott MacDonald led efforts at two of the sites along major Rhine branches: at Meinerswijk, which is the floodplain of the Rhine within the City of Arnhem, and along 14 miles (22 kilometers) of the lower River IJssel. At Meinerswijk the floodplain capacity is increased, while at the IJssel the main river bed is lowered.
Our experts were seconded to the executive branch of the Ministry, Rijkswaterstaat, to supervise technical (e.g., hydraulic, hydrological, morphological, and unexploded ordnance) and environmental studies, design and spatial planning, and stakeholder management.
Outcome
Mott MacDonald helped develop strategic solutions to cope with increased river flows without increasing the height of protective dikes, including enhancing the conveyance of the IJssel by dredging the river and making use of low-lying open land on the Rhine to store and convey water.
The aim was to enhance wetland habitats, minimize construction and maintenance costs, reduce the risk of defenses being overtopped, and improve availability of recreational space.