Regulations governing the treatment of urban wastewater have changed over the last two decades. The application of the Water Framework Directive (2000) has in particular led to an increase in the requirements of the quality of the water returned to the natural environment. In order to meet these requirements, French and European urban areas have conducted a policy of modernising their sanitation facilities. Compact and high-performance technologies for the treatment of wastewater and by-products have been integrated into the wastewater treatment plants. Today, the objective is to build and deploy innovative metrological and mathematical tools that will allow for optimised and controlled operation of these technologies.
Responsible energy use and the preservation of resources within the water cycle are also major concerns. The enactment in 2015 of the Law on energy transition and green growth, which aims to reduce French energy consumption, to favour the circular economy and to promote better waste management, is proof of this growing interest. More precisely, current major challenges include limiting consumption of energy, using renewable energies and recovering the nutrients present in wastewater.