Making room for the river by widening the floodplain
Nijmegen, Netherlands
Nijmegen is a growing Dutch city with a population of 173,556 in 2016 and a total area of 57.63 square kilometres. Located in the east of the Netherlands close to the German border, it is known for being proactive in sustainability issues and won the European Green Capital Award in 2018. The city faces a double challenge: an urgent need for geographical expansion to accommodate the growing population, and heightened risk of fluvial flooding.
Room for the River Waal Nijmegen is intended to address these challenges. It is part of the Dutch government’s Spatial Planning Key Decision Room for the River developed in 2006 to deal with the increasingly large volumes of water that rivers flowing through the Netherlands have to handle. It is a good example of the new and ongoing movement in the Netherlands to include both regional and municipal levels more actively in the decision-making and funding of water management measures, and it provides a multifaceted example of successful multi-level cooperation involving national, regional, and local authorities as well as water boards.
Challenges: The River Waal, the Netherlands’ largest river with an average width of 350 to 400 metres, passes through Nijmegen and generates a flood risk. The risk is increased by the fact that the land behind the river embankments is becoming increasingly populated and used. Projected water level increases due to climate change are likely to further compound the risk.
The River Waal is a lowland river, originating where the River Rhine crosses the German-Dutch border, and runs wide and broad until it reaches Nijmegen. The river and the floodplains then become significantly narrower and the meandering decreases, thereby creating a serious bottleneck and one of the narrowest bends in the Dutch river system, with an almost 90-degree angle. This leads to a heightened risk of rising water, as the historic floods of 1993 and 1995 demonstrated. Some quays were flooded along the river, and the entire dike ring at the northern part of the river had to be evacuated in 1995 as a precautionary measure. Furthermore, the river is ‘trapped’: the southern shoreline where the city of Nijmegen is located has no room for the river to expand due to extensive land use, whereas the northern side is blocked as a result of a dike installed. Additional pressures are created by the city’s urgent need to expand and accommodate more development.
©Jerry and Marcy Monkman
Financing: The entire programme was concluded in 2015 with a total cost of EUR 350 million financed by the government of the Netherlands. Whereas no major flood has since occurred to test the efficiency of the measures, the water levels at maximum discharge were reduced to 34.6 centimetres.
Governance: Traditionally in the Netherlands, water management projects are the responsibility of the national government (the Department of Public Works within the Ministry for Infrastructure and Water Management) and are implemented top-down with funding largely provided by the national government. One of the goals of Room for the River is to change this and to adopt a more collaborative approach to flood reduction by involving regional and local governments and other stakeholders in the process. This includes exploration of alternative investment options, decision making, design, implementation, funding, maintenance, and monitoring. The result has been a participatory and collaborative approach new in the Netherlands.
In this case, the City of Nijmegen played a particularly proactive role in co-creating the project and pushing for the integration of its development agenda with the flood protection measures. The national government, which owns the land on the shorelines of the River Waal, financed the project and was responsible for implementing and monitoring the project. The City was responsible for developing plans for the project and for integrating its planned expansion and development into these plans (for example, its expansion in the direction of Lent on the other side of the river).
Cooperation and dialogue between the parties continue to this day. Whereas conflicts occasionally arise, the collaboration has been on the whole successful and has resulted in impressive collaborative solutions. The new bridges feature a challenging and spectacular design, and the threshold that dams the upper part of the ancillary channel was specifically designed to create some flowing water during low water levels, in addition to minimizing the impact of sedimentation in the main channel. The water board Rivierenland is in charge of dike maintenance. On the other hand, the Province of Gelderland (the regional government) has a minor but regulatory role in the project by providing permits to ensure that the natural environment is preserved and protected.
Other projects in the wider Room for the River Waal have included a more active role for the regional governments. There is a clear movement in the Netherlands to include both the regional and municipal levels more actively in the decision making and funding of water management measures. An additional important success factor was Nijmegen’s collaboration with other cities such as those in the European Network of Flood Resilient Cities, which provided inspiration for the city’s plans.
Actions and impacts: The programme for Room for the Waal Nijmegen was implemented by the Department of Public Works (Netherlands) in cooperation with the City of Nijmegen and included the relocation of the existing dike 350 metres inland, thereby widening the floodplain. This was coupled with digging a secondary meander or ancillary channel (with a length of 4 kilometres and a width of 150 to 200 metres) to protect the area at the bend of the river from flooding. The result was the creation of a new island, which was turned into an urban park. The natural vegetation (grassland) on the island is managed naturally by grazing, thereby slightly contributing to flood reduction (vegetation can increase flood risk if becomes too high). To integrate the City’s need for expansion with the flood protection measures, three bridges were built to connect Nijmegen with Lent (the latter officially becoming part of Nijmegen and being called Nijmegen- Lent), and a quay was constructed.
References
- ClimateADAPT. (2014). Room for the River Waal - protecting the city of Nijme¬gen.
- European Commission (EC). (2017). Nijmegen - European Green Capital 2018. Luxemburg: European Union. Gemeente Nijmegen & i-Lent. (2016). Room for the River Waal.
- Schipperheijn, K. (2013). “Nijmegen embraces the river Waal”: How adapta¬tion to climate change gives Nijmegen a new urban waterfront. Nijmegen: s.n. UrbiStat, 2016. UrbiStat AdminStat - Municipality of Nijmegen.
- Woorden, M. A. (2006). Spatial Planning Key Decision ‘Room for the River’: investing in the safety and vitality of the Dutch river basin, Netherlands. Ministry of Transport, Public Works and Water Management.
©Cameron Davidson
