Managing water across the flood-drought spectrum – experiences from and challenges for the Netherlands

Abstract

Recent impactful hydrometeorological events, on both the extreme wet and dry side of the spectrum, remind policymakers and citizens that climate change is a reality and that a shift in water management solutions is required. A selection of policy-shaping events in the Netherlands shows that both floods and droughts have occurred historically and continue to occur, causing significant impacts and challenges for water resources management. For decades, water management in the Netherlands has focused on implementing flood prevention policies, mostly prompted by specific events. The occurrence of droughts did not lead to comparable significant transitions in water management. The bias toward adaptation measures on the wet part of the spectrum (i.e., floods), increases vulnerability to dry extremes (i.e., droughts) as experienced in 2018-2020 and 2022. A required long-term, integral vision to rethink the existing water management system is challenging as droughts and floods act on different time scales. Furthermore, there is a fierce competition for land use and water use functions. 'Transformation pathways', applied across the full flood-drought spectrum, could provide a valuable framework in the development toward a sustainable management of water resources, involving stakeholders for just and equitable transitions and translating long-term visions into pathways for action. Impact statementHydrometeorological extreme events, that is, floods and droughts, have major impacts on ecosystems and sectoral water uses such as shipping, agriculture, industry, energy, and drinking water. From looking back on a selection of historical events in the Netherlands, we learn that significant changes in policy and measures have been implemented in response to extreme hydrological events, especially with regards to floods. However, from recent extreme drought (2018)(2019)(2020) 2022) and flood conditions (2021) and future climate projections, it has become clear that optimization of the current water management system will not suffice. A transformation is needed to deal with future hydrological extremes, requiring modifications in water system, water management, water use, and governance. We need to design, manage, and use the water system in a way that resilience to both floods and droughts is increased. This requires methods and tools to stress-test the system for both extremes, and knowledge of measures that reduce both risks. In regional adaptation strategies, the full flood-drought spectrum should be managed in a balanced way. A transformation of the current water system and water management will not always and at all locations be beneficial for all sectors. Stakeholder interactions are needed for just and equitable transitions and for translating long-term visions into concrete pathways for action.

KNMI'23 Climate Scenarios for the Netherlands: Storyline Scenarios of Regional Climate Change

“…The choice for these three variables was motivated by the fact that precipitation changes, according to experts consulted, are most relevant for climate adaptation in the Netherlands. Increased winter precipitation gives higher probabilities of high river discharge with consequences for water safety, while decreased summer precipitation gives higher probabilities of drought and potential fresh water shortage, both of which require substantial adaptation (Bartholomeus et al., 2023). Furthermore, the spread in the projected change of precipitation is substantial, and therefore allows the formation of distinct storylines: some models project an increase of annual total precipitation, others project a decrease (Figure 4a).…”

“…The two scenario variants for the regional response have been designed to capture that part of the uncertainty in the regional climate response that has largest relevance for the locally most prominent climate adaptation issues: water security and water availability (e.g., Bartholomeus et al., 2023; De Graaf et al., 2009; J. De Vries & Wolsink, 2009).…”

“…The KNMI'23 climate scenario storylines focus on water safety and water availability. Both extreme precipitation leading to high river discharge and low precipitation amounts causing drought, in combination with sea level rise, are important effects of climate change in the Netherlands that require adaptation (Bartholomeus et al., 2023; De Graaf et al., 2009; J. De Vries & Wolsink, 2009).…”

Tackling Growing Drought Risks—The Need for a Systemic Perspective

“…For example, existing water/drought risk management and adaptation plans and strategies should be reviewed, and where necessary revised, to evaluate if and how these are cognizant of possible compounding, cascading and systemic effects of droughts and potentially concurring hazards, and also of possible response risks and maladaptations. In some cases this might require transformation of the water management system, rather than modest revision and optimization (Bartholomeus et al., 2023). As risks cannot be eliminated from systems, managing the systemic nature of drought risks also implies that we have to engage with questions of which risk levels are acceptable and fair for whom, and if, and how, the possible impacts of exceeding safe and just water boundaries can be transferred for example, through drought/climate risk insurance or financial instruments, such as dedicated drought funds.…”

“…

Droughts are temporary, recurring, usually slow-onset water deficits that can lead to devastating impacts on many sectors and systems and, eventually, affect ecosystems, entire societies and economies (Chiang et al, 2021;IPCC, 2022;Pokhrel et al, 2021; UNDRR, 2021). These water deficits are caused by the interaction of meteorological imbalances propagating through the hydrological cycle and human activities (Bartholomeus et al, 2023;Van Loon et al, 2022). Drought impacts, resulting from an inbalance between water availability and water needs, are severe, spatially and temporally complex, interlinked, and often slowly evolving, rendering their assessment a challenge.

…”