A scenario analysis of climate change and adaptation measures to inform Dutch policy in The Netherlands

The Drentsche Aa catchment in The Netherlands, which has nearly untouched natural river valleys, is a designated Natura 2000 area. Agriculture is practiced on the adjacent higher-lying ground. A set of measures was drafted to achieve climate-proof solutions in the short term by reducing the effects of a drier climate on nature and agriculture. These measures must have no adverse effects. In order to check this, the Hunze and Aa’s Water Board investigated the feasibility of using groundwater for sprinkler irrigation in parts of the catchment. In the study, the SIMulation of GROundwater and surface water levels (SIMGRO) hydrological model was used in order to model future scenarios with different water level strategies and climate scenarios. The modelling examined various measures in the nature and agricultural areas to optimise the hydrological situation for both land use functions. In addition, the effect on the nature areas of abstracting groundwater for irrigation was determined for buffer zones of different widths. The findings have indicated the policy direction to be taken by both the water board and the province, as well as offer them opportunities to deal with the requests for withdrawals in the near future by the means of future-proof general rules.