The new EU circular economy package is committed developing a number of actions to promote further uptake of water reuse wherever it is cost-efficient and safe for health and the environment.

The main objective of the CLEaN-TOUR project is to develop knowledge, technologies and tools on wastewater treatment in order to facilitate expanding urban water reuse in touristic regions. In order to do so, the CLEaN-TOUR project will analyze two wastewater treatment scenarios: centralized systems, with a conventional wastewater treatment plant (WWTP) of a touristic city, and decentralized systems which consists of applying water segregation, i.e.  grey water and treatment onsite where the wastewater is generated, i.e. in hotels. The CLEaN-TOUR project will tackle three main issues regarding water reuse in touristic cities: (i) the removal of pathogens and micropollutants, (ii) the evaluation of the potential risks of water reuse, and (iii) the difficulties in selecting the most adequate scenario (centralized or decentralized) and related treatment technologies.

First, in the CLEaN-TOUR project new analytical procedures for micropollutants (included in the Watch List of the EU Decision 2015/495 and in the Directives 2013/39/EC and 2008/105/EC) and non-conventional microbiological parameter (included in the EU legislation draft about minimum quality requirements for water reuse in agricultural irrigation and aquifer recharge) will be developed for water and solid (i.e. plant) samples.

After that, different technologies will be developed with the objective of increasing the quality of the reclaimed waters. Osmotic membrane bioreactors, hydroponic technologies and solar electro-oxidation will be developed as decentralized systems and as safety multibarrier treatments for micropollutants and pathogens. The results obtained will be compared with other technologies in both centralized and decentralized systems. In order to complement the efficiency results of the technologies, the use of reclaimed water for urban water reuse (irrigation of urban gardens, urban farming, hotel water recycling) and its associated risk will be evaluated in centralized and decentralized scenarios.

Finally, the knowledge generated will be encapsulated in a decision support tool in order to facilitate the assessment of centralized and decentralized water reuse schemes, to support the comparison and selection of the most feasible treatment technologies, and to raise awareness about the importance of water reuse in touristic cities. The CLEaN-TOUR project will demonstrate the safe use of reclaimed water for irrigation and other uses, thus illustrating water reuse as a step forward towards a circular economy in touristic regions.