THE PROBLEM

The Paris Sanitation Authority (SIAAP), established in 1970, transports and treats wastewater for nine million people in and around Paris. It manages 440 km of pipe, six treatment plants, and 12 stormwater retention basins. With a staff of more than 1,770 employees and an annual budget of 1.3 billion euros, SIAAP covers four areas: Paris, Hauts-de-Seine, Seine-Saint-Denis, and Val-de-Marne, along with 180 municipalities in the Val d’Oise, Essonne, Yvelines and Seine-et-Marne. Because tourism is high in these areas, odor control is especially important. To keep tourism up and unpleasant odors from wastewater treatment down, SIAAP needed a firstclass air quality solution.