- Three
Nature-based Solutions implemented in three demo sites
- 120
stone check dams built
- 2023-2028
Implementation timeline
Solutions
Through the Cardimed (climate adaption and resilience demonstrated in the Mediterranean region) project funded under the EU Mission on Adaptation to Climate Change, the Aegean Islands in Greece are implementing innovative approaches to water management, combining modern and traditional techniques.
Circular wastewater treatment
In Lesvos, domestic waste water is treated using a small-scale, nature-based system in the Antissa area. The system uses vertical subsurface flow and constructed wetlands to clean waste water, which is then reused to irrigate nearby agroforestry fields supporting mixed-species cultivation. At the same time, nutrients are recovered and returned to the soil, creating a circular system where both water and nutrients are reused efficiently.
Traditional stone check dams
In Sifnos, traditional water management techniques have been revived through the construction of 120 locally sourced drystone check dams across two seasonal streams in the Kamares catchment. These structures reduce run-off during intense rainfall events. The system is complemented by sensors monitoring water levels and soil moisture, along with an online weather station tracking hydrological and climatic conditions.
Rainwater harvesting
In Mykonos, the project combines water collection and irrigation systems at two sites. Rainwater and storm water are collected, treated and stored in detention tanks and reservoirs. The water is then reused for agriculture through optimised, sensor[1]based irrigation systems. At one site, the system also supports aquifer recharge during wet periods, ensuring water availability during droughts.
Co-benefits
Economic
These water management solutions generate cost savings and economic opportunities. By reducing reliance on energy[1]intensive treatment systems and imported water, operational costs are significantly lowered. Rainwater harvesting supports agricultural productivity, particularly for high[1]value crops, while wastewater reuse reduces fertiliser costs. Over time, these measures help reduce climate-related losses and strengthen the economic resilience of the islands.
Social
The interventions strengthen community resilience and cultural continuity by combining citizen engagement with traditional knowledge. Reviving historic water management practices fosters intergenerational knowledge exchange and community pride. Outreach activities, such as walking tours, open days and focus groups, enhance stakeholder engagement and participation. These bottom-up approaches also encourage residents and farmers to move towards greater water self-sufficiency, reinforcing social cohesion.
Environmental
The nature-based water solutions deliver significant environmental benefits by addressing both water scarcity and extreme weather impacts. In Lesvos, circular wastewater systems reduce reliance on synthetic fertilisers, improve soil fertility and support biodiversity, while treatment wetlands provide habitats for native species. In Sifnos, reduced run-off limits soil erosion and protects ecosystems. In Mykonos, rainwater harvesting reduces pressure on overexploited aquifers, helping preserve freshwater ecosystems.
Replicability
Replicating nature-based water management: models, tools and finance pathways from the Aegean Islands to other regions
Best suited for
This model is particularly well suited for small island and other remote arid or semi-arid areas facing acute water scarcity, recurrent droughts and flash floods. These conditions often lead to degraded freshwater sources and seasonal water stress. It is especially relevant in contexts where traditional water management approaches exist but where centralised infrastructure is costly, difficult to maintain or impractical due to geographic constraints.
Stakeholders' role
The approach relies on a collaborative governance structure. EU-funded projects work closely with municipalities and regions to provide strategic direction and project coordination, while citizens, local experts and community groups actively contribute to on-the-ground implementation. This ensures strong local ownership and adaptation to site-specific conditions.
Built-in scalable tools
Scalability is enabled by the modular nature of the interventions. Solutions can start as pilot sites and be progressively expanded over time. The combination of traditional water management practices with modern monitoring technologies improves both affordability and effectiveness. In addition, adaptive management supported by real-time monitoring systems allows continuous learning and improvement during replication.
Funding pathways
Implementation typically combines EU funding with national and municipal resources. EU climate adaptation programmes can help initiate projects, while local budgets and project-based financing ensure continuity, maintenance and upscaling over time.
On our islands, water is life – and resilience is a duty for us decision-makers. By reviving traditional wisdom and
pairing it with modern approaches and especially nature-based systems, scientists have proven that the Aegean
can secure water, protect communities, and power local livelihoods even as droughts extend and extremes intensify. These solutions work because they are designed for our geography and governed with our people.
