This deliverable presents the implementation progress and results of the innovative technologies
demonstrated across the IMPETUS demo sites during the period M1-M49 of the project (01/10/2021–
30/09/2025). It covers the full set of activities carried out under WP4 Tasks 4.5.1 to 4.12, which together
form Bundle 2: Innovative Technologies Implementation.
Bundle 2 aims to demonstrate a suite of advanced technical solutions that increase climate resilience
across diverse geographic, hydrological, and socio-economic contexts. The bundle includes
decentralised water reuse systems, digital modelling tools, pathogen monitoring technologies, sediment
transport modelling, multi-agent water balance models, decision-support systems for heat and flood risk,
and early-warning technologies for geological hazards. These solutions collectively reinforce the
broader WP4 objective of testing and validating multi-benefit adaptation innovations that can be scaled
across Europe.
The 15 tasks reported in this deliverable demonstrate substantial progress toward climate-resilient water
management, environmental protection, and risk reduction. Task 4.5.1 deployed a hybrid decentralised
fit-for-use water reclamation system in the Coastal demo site (Catalonia), producing high-quality
reclaimed water for irrigation and cleaning within a touristic complex and validating decentralised reuse
under highly variable seasonal demand. Task 4.5.2 implemented a Sewer Mining unit in East Attica
(Mediterranean demo site), integrating real-time data, energy-autonomous operation, and co-created
adaptation services. Task 4.5.3 developed a water-energy simulation and optimisation model, enabling
the operator of the East Attica system to explore climate-proof operation strategies and circulareconomy pathways.
Across several additional tasks, advanced modelling and monitoring capabilities were demonstrated.
Tasks 4.6 and 4.7.1 developed computational tools for sediment transport and regional water balance
simulation, supporting adaptation measures under hydrological and demographic pressures. Tasks
4.7.2 and 4.10.1 - 4.10.3 delivered decision-support systems that integrate multi-layer data for WEFEnexus planning, heat stress management, and flood risk visualisation, many of which are connected to
digital twin environments. Tasks 4.8.1 and 4.8.2 tackled climate-exacerbated water quality risks by
improving bathing water management during storm events and assessing drinking water resilience to
pathogens. Finally, Tasks 4.11 and 4.12 implemented technologies for urban climate proofing in coastal
settings facing sea-level rise and for geological and avalanche early-warning systems in the Arctic and
mountainous demo sites.
Together, the technologies demonstrated under Bundle 2 provide actionable, scalable, and evidencebased adaptation options. The solutions directly support regional water resilience, enable cross-sectoral
decision-making, and reduce exposure to climate-related risks. Their integration into the Resilience
Knowledge Boosters, digital twins, and participatory processes strengthens the IMPETUS vision of
empowering local stakeholders and decision-makers with robust, technology-driven adaptation
pathways.

Sensors used for wastewater flow measurements need to be robust and are, consequently, expensive pieces of hardware that must be maintained regularly to function correctly in the hazardous environment of sewers. Remote sensing can remedy these issues, as the lack of direct contact between sensor and sewage reduces the hardware demands and need for maintenance. This paper utilizes off-the-shelf cameras and machine learning algorithms to estimate the discharge in open sewer channels. We use convolutional neural networks to extract the water level and surface velocity from camera images directly, without the need for artificial markers in the sewage stream. Under optimal conditions, our method estimates the water level with an accuracy of ±2.48% and the surface velocity with an accuracy of ±2.08% in a laboratory setting—a performance comparable to other state-of-the-art solutions (e.g., in situ measurements).

https://www.mdpi.com/2073-4441/14/3/424

This Handbook provides a comprehensive overview of how water, energy and food are interconnected, comprising a coherent system: the nexus. It considers the interlinkages between natural resources, governance processes seeking coherence among water, energy and food policies, and the adoption of transdisciplinary approaches in the field.

With contributions covering a broad range of disciplinary perspectives and cross-cutting themes, the Handbook has a well-balanced mix of conceptual chapters and empirical studies. It includes a state-of-the-art analysis of the concepts and experiences in implementing the nexus in different policy environments, providing examples of successful integrated decision-making across the domains of water, energy and food. Offering a global perspective on water, energy and food security, the Handbook contains insights into achieving both national development goals and the Sustainable Development Goals. Chapters further highlight how to understand the concepts of the nexus in practice, impacts of the nexus in governance, policy and business, and methods and tools to strengthen the nexus.

Interdisciplinary and thorough, this Handbook will be critical reading for environmental management, public policy and human geography scholars. It will also be a useful tool for policymakers looking for successful examples of policy coherence towards an integrated management of water, energy and food resources.