Water: From ENEA and HERA new technologies to ensure a safe reuse for irrigation

ENEA, the Italian National Agency for New Technologies, Environment and Sustainable Economic Development, in collaboration with Gruppo HERA, has recently installed an innovative instrument for the real-time monitoring of the microbial content (i.e. E. coli) in reclaimed water. The system is added to an existing prototype, already implemented at Cesena waste water treatment plant (WWTP), in Emilia Romagna region, which allows to verify the quality of the treated water and to estimate the amount of nutrients supplied through irrigation allowing thus the adjustment of fertilization plans and the reduction of the use of chemical fertilizers.

Such a monitoring system, presented a few days before the World Water Day of 22^nd March, has been acquired within a PNRR project for the advantage of the agricultural sector^[1], devoted to the production of nutrients and fertilizers from agro-industrial wastes and sewage sludge.

The instrument has the capability of detecting through enzyme reactions the concentration of microorganisms as Escherichia coli in less than 2 hours, a very low time if compared to the 24 hours needed by the official methods; moreover, it grants a higher monitoring frequency, quick maintenance service and the real-time assessment of appropriate reuse destinations for reclaimed water, according to the European Regulation on wastewater reuse in agriculture and the approach of risk minimization.  

“The reclaimed water reuse represents an interesting solution to be implemented in the view of closing the water cycle and tackling the decrease of water availability, especially in drought periods, which nowadays are increasing their occurrence”, stated Luigi Sciubba, researcher at the ENEA Laboratory of Technologies for the use and sustainable management of water and wastewater”, who concluded that “The reuse practice could represent a useful support for the productivity of factory systems, first of all farms, that could take advantage from the exploitation of a non-conventional water resource also able to supply nutrients to soil and plants”

This innovative instrument integrates the prototype realized in the framework of VALUE CE-IN project, funded by the Emilia-Romagna Region and Development and Cohesion Fund, being inspired by the principles of the European Regulation 2020/741, entered into force on June 2023 and aimed at promoting and aligning the reclaimed water practices in EU Countries. Indeed, the European legislation indicates four different classes of cultures, related to treated wastewater quality level, defined on the basis of a few chemical, physical and microbiological parameters, including microbial content, that could be monitored through Escherichia coli analysis to contribute to the overall risk minimization.