Consortiums work out long-term solutions for sea level rise

Three consortiums of government, knowledge institutes, engineering and design firms, and hydraulic engineers are teaming up to make drawings and calculations about the future planning of the Netherlands against the background of sea level rise. As part of the Sea Level Rise Knowledge Programme, the consortiums are elaborating a range of solutions for the climate-resilient structuring of our country for 2100 and beyond.

Sea levels are rising, but it is uncertain how quickly. On the basis of the latest scientific information, we should assume that sea levels on the Dutch coast in about 2100 will be between 30 cm and 1.2 metres higher than they are today. If Antarctica’s land ice melts faster due to global warming, the rise could accelerate: in that case, sea levels could rise 2 metres by 2100 and continue to rise after that.

Scenarios for sea level rise

The Minister of Infrastructure and Water Management and the Delta Commissioner launched the Sea Level Rise Knowledge Programme in 2019 to investigate possible consequences for the Netherlands. Government and the scientific world are working together on studies of different scenarios for the rate and extent of sea level rise. The Knowledge Programme is looking at how a sea level rise of up to 5 metres will affect our current water system. It also is also investigating the steps we can and should take now so that we can continue to live and work here safely in the long term.

Basis for spatial planning

The consortiums who are now going to work will conduct an initial work-up of earlier plans and area meetings and the scenarios that Deltares mapped out previously for the long term. This should provide a picture of what is, and is not, technically, physically and spatially possible, even if there is a large rise in sea levels. On that basis, it will be possible to look at where, and how much, space we will need in the future for measures such as dike upgrades, water storage, pumping or even land reclamation. This means that the work of the consortiums will provide important information for the decisions we are now making in our spatial planning, for example for housing and the energy transition.

Seawards, flexible adaptation and protection

The consortiums are focusing on the solutions ‘seawards’, ‘flexible adaptation’ and ‘protection’. The ‘seawards’ consortium will work on the further elaboration of the option of extending our country in the seawards direction with a second coastline. The ‘flexible adaptation’ consortium will provide a concrete description of the solution in which we adapt land use to sea level rise, raising land and adaptive construction - for example with floating buildings or buildings on piles. The ‘protection’ consortium is investigating the option in which the coast is protected against flooding and erosion with dikes, sand nourishment and wetlands, and in which the river arms are completely or partially closed off with dams or storm surge barriers, and excess water is pumped out (‘open and closed protection’).

A total of twenty parties are participating in the consortiums, working together under the banner of the Water Top Sector. The consortiums are expected to complete their work by the end of this year. November will also see the publication of the intermediate review of the Knowledge Programme with a compilation of all research conducted until that point by a range of parties for the Knowledge Programme.