Risk assessment for drought

For the assessment of Dutch drought risk, user specific information is available in the Climate Impact Atlas. The next section mentions the risk information available per user. Additional information can be found at the Royal Netherlands Meteorological Institute (KNMI), including indicators such as precipitation deficit, soil moisture, and drought indices like the Standardized Precipitation-Evapotranspiration Index (SPEI) and the Palmer Drought Severity Index (PDSI). Furthermore, the National Groundwater Monitoring Network (LMG) and models from the National Water Model offer insights into current and average groundwater levels, such Lowest Groundwater Level accessible in the Climate Impact Atlas.

Built-up areas

One of the large risks of drought is the effect on foundations. The risk can be distinguished into the risk on (1) pole rot and (2) differential settlement.

Low levels of groundwater result in contact between wooden poles and oxygen, which results in rotten wooden poles and instable foundations. National datasets for pole rot risk are available on the Climate Impact Atlas. The map indicates the risk of pole rot at the neighbourhood level. The pole rot risk map comprises two underlying maps: Percentage of wooden piles and Vulnerability of the neighbourhood for pole rot. Both the current as well as the future 2050 scenario is available.

Foundation damage due to differential settlement is a persistent challenge. Uneven soil compaction results in structural stress, potentially causing cracks or tilting of the foundation. Information on differential settlement on neighbourhood level for 2050 can be found in the Climate Impact Atlas.

Specifically for newly developed neighbourhoods the availability of drinking water is a large issue. Groundwater protection zones are essential to safeguarding future supplies. These factors are outlined in groundwater protection guidelines.

Transport

During a drought, the entire transport sector is affected. Low water levels on shipping routes reduce the cargo capacity of vessels, requiring additional ships or alternative transport methods to handle the remaining freight. This leads to increased transportation costs. Detailed information on how drought impacts the main waterway network is available in the Climate Impact Atlas by Rijkswaterstaat. Their stress test results can also be accessed through the Rijkswaterstaat publication portal.

Another effect of drought is salt intrusion, specifically at locks. It poses a serious challenge for the transport sector. As freshwater flow weakens, saltwater infiltrates inland waterways, affecting shipping routes and port operations. Increased salinity can disrupt cargo transport by limiting access to freshwater-dependent locks. Additionally, delays arise when mitigation measures, such as clustering ships to reduce lock openings, are implemented. Ports may need to adjust dredging schedules and vessel loading procedures to accommodate changing water conditions. Information about salt intrusion can be found in the Climate Impact Atlas.

Agriculture

The agricultural sector in the Netherlands is increasingly affected by drought. Drought reduces crop yields, especially on dry or heavy soils. The Climate Impact Atlas includes maps for loss of crop production, specifically grass, for the current situation and 2050. Also soil quality declines, and water shortages emerge. Shortage of groundwater effects the soil moisture, which influences the quality of the soil. Rijkswaterstaat monitors the Standardized Groundwater Index (SGI) for the Netherlands in the droogtemonitor.

Wageningen University & Research developed the toolkit Waterwijzer Landbouw for quantifying impacts of water management and climate on agricultural production. Waterwijzer Landbouw consists of a metamodel (WWL table) and a calculation tool (SWAP-WOFOST). The WWL table provides insights into crop yields and economic effects under drought, waterlogging, and salinity based on extensive simulations. For specific situations, the model tool offers tailored calculations, such as for unique soil types or extreme weather, including impacts on farm operations and economic outcomes.

Industrial / energy sector

Drought increasingly affects the industrial sector, energy production, and data centres, primarily due to growing pressure on water availability. Many industrial processes rely on cooling water, which can include drinking water, and on groundwater extraction for production purposes. As droughts become more frequent, these water sources are under greater strain.

Nature

Drought poses significant risks to nature, particularly groundwater-dependent ecosystems and protected Natura 2000 areas. These areas rely on stable groundwater levels and groundwater discharge (WFD streams) to maintain biodiversity and ecological functions. During prolonged dry periods, water shortages can severely impact these sensitive habitats, leading to degradation and loss of species. In times of scarcity, drought susceptibility nature and Natura 2000 sites are prioritised for water allocation, reflecting their ecological importance. However, in freely draining areas, this prioritisation is not feasible once drought has (almost) set in. This highlights the need for more structural measures in these regions.