The REWAISE project has demonstrated significant progress that clearly surpasses the state of the art in multiple areas of the urban water cycle. In terms of water efficiency, the Living Labs have achieved reductions of over 30–40% in drinking water consumption thanks to a combination of rainwater harvesting, greywater recovery and digital network optimisation, whilst the digitalisation of DWTPs and WDSs has enabled operating costs to be reduced by over 40% and leaks by 42%, far exceeding what current commercial solutions offer. In resource recovery, brine mining technologies have reached TRL 8–9, extracting Mg, Ca, NaCl and Li with purities exceeding 95%, and energy consumption well below state-of-the-art levels (for example, CapDI at 0.7 kWh/m³ compared to 3 kWh/m³ for reverse osmosis). Pilot projects for the recovery of nutrients, biogas and fertilisers including struvite, ammonium and biomethane; have demonstrated superior performance and efficiency compared to conventional technologies, positioning REWAISE as a European benchmark in the circular water economy. Furthermore, innovations in smart networks, urine separation, predictive systems and digital twins consolidate a set of technological advances that surpass what is available on the market and validate the maturity of the project’s solutions.
Before the project concludes, the aim is to consolidate all the results that will fully demonstrate a smart, carbon-free water cycle across the nine Living Labs, in line with the project’s objectives. This includes increasing the recovery of reclaimed water, maximising the recovery of nutrients and minerals, and completing the validation of digital solutions for decision-making, DWTP–WDS coordination, and the predictive operation of sanitation and wastewater treatment networks. Furthermore, it is planned to complete resource recovery systems (such as struvite, ammonium and critical minerals), finalise pending pilots related to predictive models and water quality (THMs, algae), and strengthen the governance models and new regulatory frameworks demonstrated in each Living Lab.
The project’s current and projected results indicate a highly positive environmental, economic and social impact. REWAISE promotes more efficient water use and a significant reduction in emissions, whilst creating new business and employment opportunities centred on innovative technologies. The Living Labs have demonstrated reductions of 39–42% in network costs and losses, as well as a 42% reduction in drinking water consumption thanks to collection and reuse solutions. The recovery of minerals and nutrients exceeds initial targets, creating new value chains, whilst energy recovery through biogas and biomethane reduces the carbon footprint by more than 100% in specific processes and generates direct municipal savings. Technologies such as IWAN and inspection robots enable the detection of up to 86% more leaks and speed up repairs by 74%. Furthermore, the creation of spin-offs, the mobilisation of over €20 million and strong public engagement, with 87% acceptance of reuse applications, consolidate the social impact and facilitate the replication of these solutions across Europe.
