The Delta Programme sets out new strategies to ensure that flood defences and freshwater supplies will be maintained sustainably and robustly in 2050. Our country needs to maintain its capacity to manage more extreme climate conditions in flexible ways. A range of government agencies, public organisations and research institutes have collaborated intensively on these strategies, with Deltares as the main supplier of knowledge. Our contributions were used to develop sound and supported decisions: delta decisions about flood protection, the availability of fresh water and water-robust spatial planning, as well as two area-specific delta decisions for the Rhine-Meuse estuary and the IJsselmeer area. As well as providing the knowledge support, Deltares also put the structure of the ‘coastal foundation’ onto the agenda. This led to a proposal for the ‘strategic Sand decision’. The delta decisions will be definitively anchored in the successor to the National Water Plan.
Good plans for the future
Climate change requires action to safeguard defences, freshwater supplies and robust spatial structuring. Floods have a greater impact now than 50 years ago. More people live in the Netherlands, and so potential casualty numbers are higher. Almost 60% of the Netherlands could be submerged. That area includes the country’s largest cities, and its economic centre. Proper flood defences are important to prevent economic damage, whether from sea or river floods. That is why the Netherlands has to look well ahead and develop good plans for the future.
Adaptive Delta Management
Deltares has played a leading role in getting the consequences of climate change onto the agenda and focusing the spotlight on them, as well as in developing an adequate approach to coping with those same consequences. The new Adaptive Delta Management approach is central to the Delta Programme and it makes ‘coping with uncertainties’ possible. Short-term measures are assessed in the light of long-term perspectives and elaborated in adaptation paths. There is a deliberate emphasis on keeping options open for the future. And on responding flexibly to new opportunities and new insights.
Delta Scenarios have been developed by a consortium led by Deltares. The scenarios sketch out the perspective for the long term: possible futures have been worked out with qualitative and quantitative information about the climate, water systems, water use and land use. The qualitative information consists of storylines and maps. The quantitative data are presented as key figures relating to, among other things, temperature, rainfall, river discharges and geographical data sets for land use, land subsidence and salinisation in the Netherlands.
Short- and long-term measures
The delta decisions provide direction for the steps taken by the Netherlands in response to climate change in the short and long terms:
- New standards for flood defences (from 2017 onwards). These relate not only to flood probabilities, but also to the combination of flood probabilities and the possible consequences (risk approach). The extent of the consequences determines the protection level.
- The availability of fresh water for agriculture, industry and nature becomes more predictable. The level of freshwater supplies is worked out for each region and for each sector.
- Spatial planning will become more climate-resilient and more water-robust.