FROM SEWAGE WATER TREATMENT TO WASTEWATER REUSE. ONE CENTURY OF PARIS SEWAGE FARMS HISTORY

The irrigation fields of Paris have been used for 100 years. Their soils contain heavy metals in the topmost layer. Metals come from raw sewage and from digested sludge. Vegetables concentrate metals but their average content remain lower that the recommended limit values. Green vegetables concentrate more than other plants. The SIAPP keeps operating irrigation fields by delivering clariflocculated water with a low metal content with the purpose of keeping some 2000 ha of green zone. The technic has also the avantage to preserve the quality of the Seine, especailly in summer.