Event Type

Drought

Start Date

1 Mar 2022

Countries

• Netherlands

NUTS

• Nederland (NL)

RBD

• Netherlands - MAAS (NLMS)
• Netherlands - RIJN (NLRN)

Duration (hours)

4320

Event severity

MEDIUM

Return period of the event

100.0 years

Event extent

41850.0 km²

Event Severity Assessment Method

A comparison was made to other drought years, especially 2018, which was another extreme drought recently occurring in Europe. The drought of 2022 was of the same severity as the 2018 drought, and had an even higher precipitation deficit already in Spring and an even lower snow cover in the Alps leading up to the event. It had some different characteristics, for example the trend in precipitation deficit, but was in many aspects of the same magnitude as the 2018 drought. The most extreme drought recorded is, however, the 1976 drought, which was even more extreme . The precipitation deficit reached almost 400 mm/year during Summer and stayed above 300 mm for approximately 3 months. Because this drought was even more extreme, the 2018 severity is categorized as medium. The return period of the 2022 drought where the Meuse discharges drop to 130 m3/s for 225 days at Monsin has a return period of approximately 110 years. The return period of the 2022 drought where the Rhine discharges drop to 1020 m3/s for 60 days at Lobith has a return period of approximately 95 years. Hence, the return period is set to 100 years.

Impact Significance

HIGH

Impact Assessment Methods

The impact has been categorized as high, but not very high, as it had an impact, but crucial functions (hence priority 1 in the Dutch water allocation scheme) could still be ensured. Additionally, the drinking water supply could still be ensured, although there were some hesitations if this was the case at one point in time. Impact 1. Reduced surface water availability is high, which is indicated by the combination of low river discharges and a large precipitation deficit. The Rijkswaterstaat Waterinfo website gives information on the river discharges in the Netherlands based on monitoring data. When looking at the low river discharges occurring in 2022 and comparing it to the 2018 drought: In 2018, the Rhine discharge at Lobith was for 125 days lower than 1020 m3/s, whilst this was solely 60 days for the 2022 drought. The low water situation, hence, occurred twice as long in 2018. However, the drought of 2022 was for 6 days even lower than 700 m3/s, whilst this was 0 days for the 2018 drought. It even reached a minimum flow of 679 m3/s. These low discharges have a large impact on navigation/shipping, salinization and the deterioration of the water quality. The Meuse discharges also dropped to 60 m3/s or below for 87 days at Monsin in 2022, compared to 102 days for the year 2018. The simultaneous occurrence of the 2022 low river discharges and the maximum precipitation deficit was very extreme, solely the 1921 and 1976 droughts were more extreme. Therefore, the reduced surface water availability is indicated as high. Impact 2. To analyse the groundwater and soil moisture in 2022 model calculations of the Landelijk Hydrologisch Model were used, specifically the submodules of MODFLOW and METASWAP, as well as timeseries of groundwater measurements derived from the Droogteportaal. The model calculations of the LHM display for the 2022 drought that the soil moisture levels are low from March onwards in the South of the Netherlands. This broadens to the Eastern part in May and is from July onwards the case for the whole of the Netherlands. These low soil moisture levels decrease from September onwards, whilst the low soil moisture continued until November for the 2018 drought. The groundwater levels, however, dropped to 1m for both 2022 and 2018 and the groundwater drop lasted long into autumn. The lower groundwater and soil moisture leads to (irreversible) damages to nature, lower crop revenues and damages to infrastructure and houses. All this considering, these drops have a high impact. Impact 3. The internal salinization was analyzed by contacting the water boards and provinces located at the coast, as well as the drinking water company PWN and agricultural organization LLTO-Noord. The drinking water company PWN and water board Rijnland have also supplied measured timeseries of chloride concentrations in the rivers during 2018 and 2022. The allowed salinization concentrations differ per area, ranging from 150 mg/l for more sensitive cultivations, whilst this is 450 mg/l for less sensitive cultivations. In 2022, the threshold of 450 mg/l was surpassed several times, however, the peaks in 2018 were higher and were persisted until later in the year as well. For the Haarlemmermeerpolder, the chloride concentration peaked at 490 mg/l in October 2022, and was for 9 months higher than the allowed 450 mg/l (40 mg/l increase).The impact of this increase was, however, lower compared to the 2018 drought, as there was still sufficient freshwater to flush and several measures have been taken after the 2018 drought. The impact was, therefore, low. Impact 4. The Vegetation Health Index is used to indicate the health and conditions of the vegetation, calculated using satellite images, land surface temperature and the Normalized Difference Vegetation Index. A value of 0.3 indicates mild droughts, whilst values lower than 0.2 indicate a serious drought. In 2022, the VHI reached values lower than 0.2 in August for the whole country. It is, however, still above 0.1, hence why it is indicated as normal. Impact 5. There were about 700-800 wildfires in 2022, of which the majority occurred in July and August. However, what stood out more was that a larger number of wildfires occurred in March and April compared to normal conditions. Wildfires cause the burning of nature areas, as well as negatively influencing infrastructure and buildings. In totality, it is uncertain how big the actual impact was. Impact 6. In the year of 2022, there were only two stops in the drinking water extractions, occurring at Andijk and Heel due to high substance concentrations, and the impact was therefore low. This is also because many adaptation measures were taken after the drought of 2018. Impact 7. The yield per hectare for agriculture during 2022 was slightly higher than average, and crop prices were also higher. This means that the agricultural producers benefitted from the dryer year, having a producer surplus of 1.22 million euros, whilst the consumer surplus was negative, decreasing with 1.01 million euros. Hence, there was a positive surplus overall in the Netherlands of 217 million euros. There were, however, additional irrigation costs, but these were not considered, and are estimated to be low. Impact 8. Because of the low river discharges in 2022, the impact on navigation seemed large (largest for the chemical chains and bulk transport). This was mainly due to the limitations in navigation depth, meaning the ships could not transport as much load and could not sail everywhere. This lead to double the amount of trips and the transport demand could only be met partially. Additionally, locks had large waiting times. The actual impact remained small, however, as the low water period in 2022 was relatively short (especially compared to the 2018 drought). The economic impact was approximately 65-165 million euros for the Netherlands.

Uncertainty Evaluation

For the agricultural revenue indicator, the additional irrigation costs during the 2022 drought were not considered, but these are estimated to be low when looking at the costs of this from the 2018 drought. The uncertainty is, hence, low. Several of the information is gathered through interviews, which is subjective to a certain extent. These interviews were, however, more often used for sketching the context and less for actual parameterization and quantification. Several impacts have been looked into, but are still too difficult or require more research to quantify, such as the influence of the 2022 drought on dyke stability, CO2 emissions, land subsidence, the nature area affected, and the specific effects in urban areas (e.g. damages to foundations and subsidence).

Event Description

The drought was extreme, because it occurred on many places simultaneously. Almost 50% of Europe was in the warning stages of crisis management in the Summer of 2022 and 17% was in the alert phase. The extremeness was, furthermore, a combination of the limited amount of snow falling in the winter in the Alps, decreasing river discharges earlier in the year, less storage in the reservoirs, less precipitation and higher temperatures (average of 11.6 °C in 2022 compared to 10.5 °C normally), hence, more evaporation occurred. The precipitation deficit was already very high in March, especially in the Eastern and Southern part of the NL, whilst this was not yet the case in 2018. During the Summer the overall precipitation deficit was inbetween 150 mm-300 mm/year, reaching a peak of over 300mm at the end of the Summer, which is very extreme.

Emergency Response Measures

Water shortages are monitored by the Landelijke Coördinatiecommissie Waterverdeling (LCW). When there are serious water shortages the water allocation scheme of the Netherlands ‘Verdringingsreeks’ is applied to allocate the available freshwater. In the 2022 drought, there were actual water shortages (level orange) for 7-8 weeks in August-September. The following measures were accordingly taken: May-June: Increasing the water levels in the IJsselmeer and Markermeer. 18 July-16 September: Putting the Klimaatbestendige Wateraanvoerverziening (KWA) for West-NL into effect. 28 July: Additional pumps for the pumping station Eefde. Regional emergency measures, such as abstraction restrictions, were mainly applied in the higher Sandy Soils to retain water and protect nature. This was mainly a restriction in abstractions for irrigation and varied in type restriction (surface vs groundwater), length (days to month) and duration (whole day or part of the day). In the Western part of the Netherlands, there were measures related to dyke protection, such as watering dykes and filling up cracks. In this area, there were also many restrictions for shipping, such as a limited time to open the locks. To reduce the salt water intrusion from the Noorzeekanaal and the Amsterdam Rijnkanaal, the Noordersluis was only allowed to be opened between 06:00 and 18:00 from July until September 2022. There was also additional water supplied to the Amsterdam Rijnkanaal to prevent the salt concentration in Diemen getting too high, and the implementation of a bubble screen to limit the mixture of saline and fresh water. In 2022, also an effective public campaign has been performed focusing on water savings, and locally more water was retained which was overseen by the water boards. In the event files, pictures are uploaded displaying which measures were taken when.

Mitigation Measures

There is a new Environmental Planning Act (2022), which represents an opportunity to manage land in an integrated manner to operationalize green water management and the combined management of surface and groundwater management. This law contributed in moving from crisis management to drought risk management.

Long Term Adaptation Measures

The 2022 drought was closely preceded by another extreme drought in 2018. Many adaptation measures have been taken after the 2018 drought to adapt to extreme droughts, such as investments in the drinking water network (leading to better use of the allowed abstractions), putting in more and better irrigation installations, drinking water companies have put up better protocols.

Sources

Hendriks, D. et al. (2024). De droogte van 2022: een brede analyse van de ernst en maatschappelijke gevolgen. Retrieved from https://www.deltares.nl/expertise/publicaties/droogte-van-2022-een-brede-analyse-van-de-ernst-en-maatschappelijke-gevolgen-achtergrondrapport www.rws.waterinfo.nl https://droogteportaal.nl/droogteportaal/web/

Contact Persons

Judith ter Maat, Deltares Esmée Mes, Deltares Marjolein Mens, Deltares Dimmie Hendriks, Deltares

Impact Types

• Environmental
• Societal and Cultural
• Economic

Impacted Sectors

• Agriculture
• Tourism & Recreation
• Industry
• Infrastructure (roads, water supply, etc.)
• Plants & Wildlfe
• Transportation and Navigation

Reference Point

51.86691893606687,6.057960260047431

Data Managers

Esmée Mes (Deltares), Judith ter Maat (Deltares), Michiel Blind (Deltares), Harm Duel (Deltares)

Last Updated

7 Jan 2025, 4:10 p.m.