The Thames Tideway Tunnel, which is currently in construction and will be operational by 2023, will significantly reduce the frequency and volume of discharges of storm sewage and improve water quality in the tidal Thames. This will reduce levels of associated chemicals in the tidal river.
The EA is working with Thames Water and other water companies to undertake extensive investigations, to assess a wide range of chemicals entering rivers through wastewater treatment works. The investigations have shown that wastewater treatment works significantly reduce the concentrations of many chemicals before they are discharged to rivers. Although cocaine is not part of these investigations, it is likely that it will be similarly affected by wastewater treatment.