Action perspectives on climate extremes in the Dutch river system: system-level impacts and mitigation strategies

Worldwide climate change affects the Dutch deltaic river system: recent dry years led to (extremely) low discharges in summer, while an extreme rainfall event in the summer of 2021 led to large-scale flooding in the Meuse catchment.
Increased sea level rise (SLR) will in turn cause higher water levels reaching further upstream, higher closing frequencies of storm surge barriers and reduced discharge capacities of sea locks. As the Dutch delta is densely populated, such negative impacts of climate change will lead to large socio-economic impacts. Understanding how climate change influences the Dutch river system in the long term (> 2100) is thus important to timely adapt to these developments.
Recent publication of the new climate scenarios by the KNMI shows that climate
change will continue to affect the climate in the Netherlands. Overall, in all scenarios the precipitation in summers will decrease, while winters will become wetter (KNMI, 2023).
Additionally, long term land-use developments, driven by climate change and population growth, will effect runoff towards rivers. This all inevitably impacts the discharge regime of the Rhine and Meuse, as well as the lateral inflow
to these rivers. Alongside, SLR is expected to increase and accelerate, with extreme scenarios of up to 8 meters SLR by 2300 (KNMI, 2023).
Besides future developments, interventions in the past still impact the river
system. An example is the ongoing bed
degradation in the river Waal due to
normalisation works in the past century, which
influences the discharge distribution at one of
the main bifurcations (Klijn et al., 2022). This
bed degradation will continue in the future (Ylla
Arbós et al., 2023).