Conservation organizations, gravel extraction companies, and the local government teamed up to create a 45km stretch of rewilded river with increased flood prevention capacity.
This rewilding project focuses on taking a previously human-altered river and returning it to a more natural state in order to facilitate increased flood protection and biological regeneration. This was done through collaborating with gravel dredging companies which wished to harvest gravel from the Meuse river. During the harvesting process they helped to widen the river, lower riverbanks and therefore expand the overall floodplain. This is the largest river restoration project in the Netherlands with it covering a 45km stretch of the river called Grensmaas. They also put 200 ha of riverside lands under naturalistic grazing regimes to help facilitate regeneration. Beaver (Castor fiber) and otter(Lutra lutra) were also reintroduced to the landscape.
Overview of context and outcomes:
This region of the Netherlands has been historically prone to flooding with major floods in 1993 and 1995 leading to residents to push for solutions to the problem. In 1980, the Meuse river system, and specifically the Grensmaas, was the only river system in the Netherlands without boat traffic. This is what had originally made it a focus point for the sand and gravel industry as a source of possible extractions. The Grensmaas river portion also flows from north to south and acts as an important ecological corridor between the upper and lower reaches of the river Meuse.
The widened river with the inclusion of floodplains and natural flow patterns has reportedly increased the areas resilience to flooding. The system is designed for one-in-250 year flooding occurrences. There was a test of the system in July 2021 when large scale flooding occurred in the basin, but all houses around the restored river area remained dry and undamaged.
The project contributed to improving habitat quality along the river and ecological monitoring studies of the intervention have reported highly successful recolonization of riverine flora and fauna.
The project has become a key draw for tourists with two million visitors coming annually generating approximately €1bn of revenue for the Meuse region.
The initial proposal for sustainable gravel extraction and restoration was created by the local natural history society (Natuurhistorisch Genootschap), Stroming Ltd and BirdLife Netherlands. This proposal was sent to the Provincial Government of Limburg and the Dutch National Government after it was made clear that they intended to implement gravel mining in the area. Current Dutch governance of the project is managed under the Consortium Grensmaas, which is made up by members from the gravel extraction sector, civil engineers and the private conservation organization Natuurmonumenten.
The total financing for this project is €550m, with the project financed mainly by companies who are extracting sand and gravel from the existing riverbed. The unique financing mechanism utilized in this restoration project ended up being the reason that it was the only large-scale river restoration not cancelled during the 2008 financial crisis.
Ecological monitoring has been conducted on the river to evaluate recolonization of flora and fauna. Monitoring also takes place to track introduced species such as otters and beavers within the system.
There was some initial community resistance to the project, but this waned as the recreation, environmental, and flood defense benefits became apparent.