An analysis conducted under SpongeBoost offers a perspective on the success of nature-based water management strategies in sponge landscape restoration. The study data was collected across 170 restoration projects spanning over 27 countries and provides a qualitative overview of the recurring trends and constraints across the projects’ strategies.

According to the results from the analysis, the most appropriate measure for nature-based water management was improving hydrology. The research pinpointed three types of landscapes that were most often found within restoration projects - peatlands, rivers and floodplains, and inland wetlands. 

For the case of peatlands, specifically located across Northern and Atlantic Europe, research showed that water table recovery brought forward the most reliable results. By using hydrological measures such as ditch blocking and rewetting, peatlands exhibited more vegetation recovery, improved habitat conditions, and reduced greenhouse gas emissions. However, since peats can take decades to form, long-term monitoring is needed to determine if water table recovery will be as successful in the long run.

Similarly, floodplains and rivers rely on hydrological connectivity to remain functional. Strategies that focus on reconnecting floodplains, removing dykes, and restoring the lateral dynamics of those landscapes proved to be most successful in reducing floods, increasing water storage, and, additionally, improving biodiversity in the area. These results show that floodplains and rivers have the potential to prevent critical climate events, however due to competing land uses and governance problems, they are not yet actively utilised.

Finally, the analysis of inland wetlands, mainly in agricultural areas, determined that simple interventions like removing drainage systems and restoring natural hydroperiods can lead to significant results for water retention and biodiversity. Still, issues that stall the process of restoration remain. For example, as with floodplains, there is no clear land ownership, and, similarly to peatlands, the landscapes are rarely monitored for longer than the projects’ duration.

To conclude the analysis, the deliverable outlines that successful restoration often depends on hydrological integrity, long-term monitoring, stakeholder engagement, and better policy integration. By implementing all these factors, good restoration practices can be sustained over time. Additionally, as a result of this research, SpongeBoost has built a framework that is directly transferable and can be used by researchers and policymakers for better evidence-based planning and design of future restoration projects.

This SpongeBoost analysis will be available in the form of a deliverable on our website soon.