Eau de Paris Catchment Protection Programme — Paying Farmers to Convert to Organic Farming to Keep Pesticides Out of Drinking Water (France)

Eau de Paris, the public water operator of Paris, protects the catchment areas that supply about half of the city's drinking water by contracting farmers rather than treating water downstream.
For 2020–2025 about 115 farmers cultivating more than 17,300 hectares (58% organic) committed to a five-year programme with a budget of EUR 46 million, 80% financed by the Seine-Normandie water agency. Between 2019 and 2023 organic surfaces across the catchment areas rose from 2,800 to 11,800 hectares.
The operator reports that pesticide use on enrolled land fell 77% in 2023 (about 55 tonnes of active substances avoided) and that concentration peaks halved in groundwater where organic farming developed strongly. Caveat: the halving was documented in the Vallée de la Vanne sector (Yonne), where about 30% of farmers converted, and may not generalise; figures are largely operator-reported. Prevention is reported to cost about three times less than remedial treatment.

Read the full analysis: https://www.eaudeparis.fr/