Question to the Department for Environment, Food and Rural Affairs:

To ask His Majesty's Government what estimate they have made of raw sewage discharged into rivers (1) annually between 2010 and 2022, and (2) annually up to and including 2030.

Event Duration Monitoring (EDM) provides information on when and for how long sewage discharges have occurred. All EDM data is published online. More information on EDM is available here (copy attached to this answer). The Environment Agency will be publishing the annual EDM dataset for 2022 in March 2023.

We have increased the number of storm overflows monitored across the network from 5% in 2016 to almost 90% now monitored, and we will reach 100% cover by end of this year. Therefore, it is not an accurate reflection to compare the number of discharges across 2010 to 2021 given monitoring was not installed at all sites at the same point in time.