On 6 November 2025, the Netherlands hosted its first National SpongeDay—a full-day knowledge event organised by the Horizon Europe SpongeScapes project, the Dutch Ministry of Infrastructure and Water Management, and Deltares. More than 140 participants from ministries, water boards, provincial authorities, research institutions, and consultancy firms gathered in Zutphen to explore this question.
Over the past 150 years, Dutch landscapes have been reshaped through drainage, ditching and straightened waterways, based on the problems and needs and climate at that time. This transformed the original “sponge landscape” into one that drains water quickly—often too quickly. Returning entirely to the past is impossible, but combining ecosystem restoration with smart technical interventions can help restore the sponge effect and better manage both droughts and floods.
Throughout the day, national and regional authorities shared how they are already working to strengthen natural water retention. Examples included local projects improving sponge functioning in the Zwolle region and policy developments—such as the national sponge-effect guide accessible on the Climate Adaptation Knowledge ortal website —designed to help authorities integrate these principles into practice.
The event connected Dutch work to the European scale, with presentations on the EU Water Resilience Strategy, and the three EU research projects SpongeScapes, SpongeWorks, and SpongeBoost. Participants reflected on what the Netherlands can learn from neighbours facing severe droughts and extreme rainfall for much longer.
Two rounds of thematic breakout sessions allowed participants to dive more deeply into topics such as groundwater restoration, soil health, multi-objective planning (ecology, water quality, liveability), and governance challenges.
The conclusion? “Sponge landscape” may be a relatively new term, but the underlying work is already happening—and gaining Momentum across the Netherlands.
This successful SpongeDay is the first of several national "SpongeDay" across SpongeScapes partner countries. Each will bring together national and local stakeholders to share knowledge, compare lessons learnt, and collectively advance Europe’s transition to water-resilient, sponge-functioning landscapes.