Three water companies will be fined a total of £168m for failing to manage their wastewater treatment works and networks, as part of the first batch¹ of outcomes from its biggest ever investigation².

The penalties proposed for consultation³ will see Thames Water fined £104m, Yorkshire Water fined £47m and Northumbrian Water fined £17m.



The penalties relate to their management of wastewater treatment works and wider sewer⁴ networks including their operation of storm overflows⁵. These are designed to release water in exceptional circumstances, when the sewerage system is at risk of being overwhelmed, such as during unusually heavy downpours or snowfall, to prevent sewage flooding into people’s homes.