Solutions
The SpongeWorks project aims to strengthen the EU’s resilience to floods and droughts by demonstrating, testing and scaling-up nature-based ‘sponge measures’. Such measures strengthen resilience to these climate hazards by improving later retention across interconnected soil, groundwater and surface water systems. Working with local stakeholders, the project develops practical, inclusive landscape-scale strategies, sharing best practices to transform water and land management for long-term climate resilience across the EU. One of the project demonstrations is within the Lèze River Basin, an area in which agricultural operations have shifted from extensive livestock systems to cultivated crops over the past decades. This change has drastically reduced the water retention capabilities of the landscape, and sponge measures and monitoring actions are being implemented to counteract these impacts.
Sponge measure implementation.
Sponge measures are being implemented on farms, public land and private property. On farms, agroecological measures such as green cover crops, temporary meadows and compost application are being implemented. Leaky dams and infiltration ponds (swales, ponds) are being built on public and private lands. Lastly, hedges and riparian vegetation, including trees and dry hedges, are being planted.
Monitoring and modelling.
The sponge measures were complemented with the establishment of monitoring stations capable of measuring both water quality and quantity. Fourteen monitoring stations were placed within wells located on private property. Two stations were placed along the Lèze River itself, namely within the Labarthe-sur-Lèze and Le Fossat areas. A further 12 monitoring stations are being installed at the downstream outlets of the 12 pilot sub-watersheds to assess the cumulative impacts of sponge measures across the catchment. The data collected has been used to complete baseline modelling of the catchment.
Co-benefits
Economic
The solutions implemented help improve the long-term productivity of the area by strengthening the resilience of the surrounding agricultural land. This is possible since the sponge measures implemented increase soil moisture retention, reducing the risks of droughts, floods, mudslides and soil erosion. Apart from this, a decrease in floods also means that there is less nitrate and pesticide pollution due to run-off. Hence, the integrity of the soil is protected using low-cost nature-based ‘no regret’ interventions, lowering the need for more costly, synthetic input and reducing damage recovery costs associated with hazards. The use of monitoring stations and modelling also means that landowners and other actors can remain informed on the quantity and quality of water in the area, leading to better management of this resource in a more informed, cost-effective way.
Social
This demonstration site ensures that measures being implemented are contextual and tailored to the needs of the area. This is done through the involvement of over 80 farmers in the development and implementation of measures, with the solutions directly protecting local farmer livelihoods. Other stakeholders are also engaged, including local authorities, water management organisations, regional advisory organisations, environmental consultancies and citizens through participatory worksite activities. This collaboration encourages knowledge sharing between different stakeholder groups, creating a sense of shared responsibility and environmental stewardship. Apart from this, it also contributes to building local capacity for climate adaptation. All in all, the resulting landscape is expected to become more resilient to climate hazards, helping to safeguard local communities.
Environmental
The implemented sponge solutions improve the landscape’s ability to retain and slowly release water, helping to reduce flooding, mudslides and soil erosion while increasing water availability during dry periods. In this way, the habitats, both in terms of wildlife and vegetation, are protected from climatic extremes and disasters. Practices such as cover crops, temporary meadows, leaky dams, swales, hedges and riparian vegetation increase soil infiltration and groundwater recharge, restoring soil organic matter and stability, and reduce surface run-off from compacted agricultural land. This can reduce water pollution from fertiliser chemicals, creating a healthier ecosystem. The use of monitoring and modelling can also help landowners and other actors decide when conservation efforts should be implemented due to water volume or pollution levels. These measures overall contribute to restoring local habitats that support biodiversity. Together, they strengthen the ecological functioning of the Lèze catchment.
Replicability
Scaling up the restoration of sponge landscapes
Combining nature-based solutions and monitoring to restore the water retention abilities of the Lèze river basin.
Best suited for
This model is best suited for river catchments that support large areas of agricultural land, while facing increasing flood and drought risks. It is especially relevant to areas where changes in land-use, particularly farming intensification or expansion, has reduced the sponging abilities of the landscape due to factors such as conversion of grasslands, intensive tillage, and the removal of hedgerows. Areas where farmers and landowners are interested in contributing to the co-design and implementation of such measures are also relevant, as it increases the potential of such measures in private and agricultural land, as opposed to only public areas.
Stakeholders' role
The model is based on a multi-actor and participatory approach. One of its main charactertics is its engagement with local farmers, who implement the sponge measures. The project partners,include two chambers of agriculture, a river management organisation, a hydraulic engineering consultancy, a research organisation, and an international association active in the water sector. This breadth facilitates communication and exchange between their different fields, which do not necessarily have a previous history of working together. Finally, the territorial coordination around the project brings together government institutions, local authorities, agricultural stakeholders, and associations, fostering dialogue and the emergence of new projects.
Built-in scalable tools
This model incorporates several mechanisms to support its replication and upscaling. This includes catchment-scale monitoring networks, which can be adapted to different catchment locations. This can then lead to modelling, as carried out in this demonstration, using the data obtained from the monitoring stations. Additionally, lessons learned from the pilot locations in this site may inform landscape-level implementation, contributing to decision-making associated with action plans that can be replicated to catchments facing similar hazards and characteristics.
Funding pathways
The SpongeWorks project has received funding through the European Union’s Horizon Europe research and innovation programme as part of the EU Mission on Adaptation to Climate Change and from the UK Research and Innovation/HM Government.
