To ask the Secretary of State for Environment, Food and Rural Affairs, what steps he is taking to (a) improve the cleanliness of drinking water and (b) reduce the low-grade contamination of water supplies by lowering the number of pathogens in water; and if he will make a statement.
Drinking Water quality in the UK is required to meet a rigorous and comprehensive set of standards laid down in legislation and set to be protective of public health and these apply to water for all consumers. These requirements are enforced by a robust regulatory regime. Additionally water companies are required to risk assess and mitigate risks of any additional substances not specifically listed and which might otherwise present a potential risk to human health.
With respect to pathogens, companies are required to have in place robust disinfection processes. The standard for bacteria indicative of pollution likely to contain human pathogens is zero (none permitted to be present). It is a criminal offence to supply water that has not been disinfected. In 2017, in England, there was one detection of E.coli from 154,431 samples taken at treatment works and 11 detections of E.coli from 186,163 samples taken from storage points in the network. In all cases action was taken to rectify any issues identified.
The Drinking Water Inspectorate provides independent scrutiny of the performance of water companies in meeting standards and publishes an annual report containing statistics on drinking water quality on its website at http://www.dwi.gov.uk/about/annual-report/2017/Summary_CIR_2017_England.pdf