"Cultural aversion to microbes, healthiness or desire for safe bathing, the applications for water disinfection are varied and the technologies used to achieve this goal are numerous. The authors looked at a simple solution to implement: the use of a reagent called performic acid. Consequently, more than two years of applied research, observations and analyzes were necessary to demonstrate its harmlessness towards the natural environment. The strength of the demonstration lies in the cross-vision of many researchers and scientists from different backgrounds who shared their studies and observations. The strength of this testimony also lies in the diversity of the application cases, including notable and sensitive receiving environments as different as the Seine, the Atlantic Ocean or the Venice lagoon. Through its intentions and results, this work is a step, moving forward the 2030 Agenda for Sustainable Development, particularly SDG 6 "clean water and sanitation" relying on the lever of SDG 17 "partnerships for the goals"." Denis Penouel, Deputy CEO in charge of Prospective