The IJsselmeer region plays a pivotal role in Dutch water management. The region is of great value in terms of the natural environment and cultural history. The IJsselmeer Closure Dam (Afsluitdijk) has made the entire region safer and has enabled land to be reclaimed. A freshwater reservoir has been created which is of benefit to agriculture, industry, and nature in a large part of the Netherlands. Society uses the lakes and their banks in many different ways, such as recreational activities, the extraction of drinking water, and shipping.
In order to continue to use all these functions to their full potential and to make improvements wherever possible, it is important to respond flexibly to new developments and insights. The Preferential Strategy for the IJsselmeer Region aims to keep flood protection and the freshwater supply up to par, and to expand flexibility. The focus in the years ahead will be on fleshing out the strategy. Pursuant to the IJsselmeer Region Pact and the IJsselmeer Region Agenda for 2050, the region is exploring opportunities regarding an integrated approach to the required measures. The Delta Decisions constitute an important point of departure and framework in this regard.
The sea level is continuing to rise, possibly at a pace faster than was originally assumed. This has already made it more difficult to discharge water from the IJsselmeer into the Wadden Sea. At the same time, expectations are that climate change will necessitate an increase in the volume of river water to be discharged into the IJsselmeer in extreme weather conditions. Conversely, during prolonged drought the supply may decrease. The level management must be able to respond to these changes, especially as climate change and economic developments are expected to result in an increased demand for fresh water.
Flood risk management
In order to secure long-term flood protection , several primary flood defence systems will be tackled:
- Work on the IJsselmeer Closure Dam will commence by the end of 2018. One of the measures involves the placement of pumps to enable forcible water discharge to the Wadden Sea;
- Work to improve the Houtrib dyke between Enkhuizen and Lelystad commenced in 2017;
- The improvement of the Markermeer dykes will commence in early 2019.
On the island of Marken and in the IJssel-Vecht delta, options have been explored regarding the application of spatial solutions to help achieve the required flood protection level. The MIRT (Multi-Year Programme for Infrastructure, Spatial Planning, and Transport) studies conducted have generated more insight into the practical applicability of the multi-layer flood risk management concept. It turns out that the IJssel-Vecht delta offers more scope for spatial measures than the island of Marken. Preparations for improvement of the dykes on this island are currently under way. The tender procedure will commence in 2019.
The freshwater supply in the IJsselmeer Region can be maintained by implementing a cohesive set of measures in the main water system (the large lakes), regional water systems (smaller watercourses, drainage water, and canals) and among consumers. The availability of fresh water will be expanded by introducing flexible water level management in the IJsselmeer, Markermeer, and Zuidelijke Randmeren lakes. In the near future, this will make a 20cm “extra layer of water” available as a structural water reserve. The new water level ordinance required to this end came into force in June 2018. This extra layer may need to be gradually increased in due course (probably only after 2050).
Rather than compensating for the increasing regional demand by allowing an increase in water consumption, the authorities in charge of the regional water systems aim to keep water consumption constant by implementing measures in the region, such as more efficient flushing and introducing adjustable weirs. Farmers and industrial enterprises will also be encouraged to save water, for example through underground freshwater storage and the reuse of process or cooling water. Agreements to this effect have been set down in the Administrative Agreement on freshwater supply measures in the IJsselmeer Region 2016-2021.
A random selection of the projects and studies:
- The Fryslân and Hunze en Aa’s district water boards are working on brook restoration in order to facilitate surface to groundwater flow;
- The province of Flevoland is working on the soil structure to improve water retention;
- The province of Groningen has explored which measures hold promise for prolonged water retention in the soil;
- In the Drentse Aa catchment area, a study has been conducted into the impact of climate change on the wet nature in the Natura-2000 areas;
- The Spaarwater programme is exploring ways to prevent salinisation of groundwater in order to ensure its use for agricultural purposes.
In the IJsselmeer Region, several examples of Spatial Adaptation have already been realised.
- In the area north of the North Sea Canal, a climate atlas has been compiled and stakeholders are actively exchanging knowledge;
- The city of Alkmaar has reconstructed the De Hoef neighbourhood and removed all the drains: rainwater is now absorbed into the soil. This has proven effective;
- On 4 July 2018, administrators of the regional governments, the district water board, and the Community Health Services agreed to embark on climate-proofing the West Friesland region.
IJsselmeer Region Pact
The regional parties involved have joined forces in the IJsselmeer Region Administrative Platform to monitor progress, to schedule measures, and ensure a proper exchange of information. However, the ambitions of the platform extend beyond the Delta Programme. They also involve capitalising on linkage opportunities, synergy, and reinforcing spatial quality in combination with new (economic) developments. On 6 March 2015, government authorities and NGOs in the IJsselmeer Region set these ambitions down in an administrative agreement, the “IJsselmeer Region Pact”.
Delta Programme 2019
Read about the progress made in the IJsselmeer Region in Delta Programme 2019.