Climate-proof Netherlands

How can the necessary adaptation to climate change be linked to the spatial development of the Netherlands in such a way that a contribution is made to the economy and spatial quality? That is the central question for this design research. Given the complexity and the many uncertainties, it is impossible to give a definitive answer to this question. But we can map out opportunities and options. Because there is definitely something to choose from.

This report has been prepared in the context of the Climate-proof Netherlands (KBNL) research program. This research program has been carried out by the Netherlands Environmental Assessment Agency, commissioned by the Ministry of Infrastructure & Environment. The aim was to bundle existing knowledge about the consequences of climate change and to develop a strategy to make the Netherlands climate-proof. Various research institutes contributed to this. The results are summarised in the report “A delta on the move” (PBL, 2011).

The design research is based on the principle “increase resilience where possible, offer resistance where necessary”. “Resilience” is about providing more room for natural processes and learning how to deal with uncertainties. This includes concepts such as “room for the river”, “moving with the sea” and “function follows water level”.

The complete report (in Dutch) can be downloaded here:Rapport Klimaatbestendig Nederland

LOCATIONNederlandCLIENTPlanbureau voor de LeefomgevingMinisterie van Infrastructuur & MilieuCATEGORYResearchPERIOD2012STATUSPublished

NAtional framework

Below is an overview of the most important climate challenges for flood risk management and freshwater supplies. After all, water management is a key factor in making the Netherlands climate-proof. We then discuss the relationship with the most important land use sectors: nature, urban areas and agriculture.

We list a number of promising opportunities for linking these sectors, on the scale of the Netherlands as a whole. We then translate this to the regional scale. It is precisely at that scale level that the real tasks, opportunities and dilemmas are clearly highlighted. The national framework is essential to put it in the right perspective.

A number of regional elaborations are discussed below as an illustration.The report can be consulted for the other elaborations.

North Netherlands

The Wadden Sea attracts sand and sludge takes place on the outside dyke polders along the sea dyke, sometimes a few millimeters a year. The inland dyke clay polders are relatively high and form a natural seawall for the peat polders in the hinterland. There is, however, soil subsidence due to tectonics, settling, gas extraction and salt extraction. In combination with the sea level rise, this means that the sea wall must also be strengthened along the northern coast. The coastal zone here also has to do with increasing salinisation. Due to the relatively high location, the options for freshwater supply are limited.

Three zones can be distinguished within the Northern Netherlands with different climate challenges:

coastal zone with salinization problems;
peat zone with subsidence problems;
clay zone with relatively few restrictions.

In the coastal zone, a switch to saline crops is imaginable, both for food production and for other purposes. An example is algae cultivation.

The peat zone between the clay polders and the higher sandy soils is in picture as a climate corridor for water and marsh ecosystems. A more natural water level management is beneficial to reduce subsidence and the intake requirement. Part of the current agricultural land will have to be converted into a nature reserve for this.

The clay polders between the peat zone and the coastal zone will continue to be suitable for large-scale, land-based agriculture in the future. The restoration of natural water supply from the higher sandy soils, via seepage and streams, offers an alternative to inlet from the IJsselmeer.

ijsselmeer region

The large waters of the IJsselmeer region are all designated as Natura 2000 sites and form a crucial core area in the swamp climate corridor. Bordering on the Wadden Sea, the IJsselmeer also has significance for the dune and coast climate corridor. The future water management of the IJsselmeer strongly determines the ecological development possibilities. The current water and nature quality is far below standard.

The IJsselmeer discharges through the drain locks in the Afsluitdijk on the Wadden Sea. With rising sea levels, this becomes more difficult due to the decreasing level difference. In addition to safety, the freshwater supply plays an important role. The IJsselmeer is seen as a collection basin for the water inlet of the north and west of the Netherlands.

As a thinking experiment we want to paint a picture of the IJsselmeer as a dynamic delta water.

By creating (possibly lockable) openings in the Afsluitdijk, the tidal effect can be restored up to Zwolle. The ecological benefits seem considerable: the exchange possibilities for fish are being improved and the intertidal area is being expanded. Depending on the dimensions and the design of the inflow openings, sediment management and water quality can also improve. With this solution, the water level will gradually rise with the sea level.

A condition for the restoration of tidal activity and the fresh-salt gradient in the IJsselmeer is that water withdrawals for agriculture are gradually being phased out. This is at odds with current policy, in which the function of the IJsselmeer as a freshwater basin is leading. But how crucial is that function for the Dutch economy? In any case, research has shown that measures to also supply water to the West of the Netherlands from the IJsselmeer (changes to locks, inlet works and watercourses) are not cost-effective.