Compliance and complaints
Microbiological detections at works
Southern Water – multiple treatment works
In February, Southern Water detected coliform bacteria in samples collected from the same day from three of its treatment works (Brede, Eastling and Sompting). The company undertook a thorough investigation into these detections, and it was identified that all of these breaches related to the same colony type (Klebsiella pneumonia) but were taken by separate samplers, from different regions of the company supply area. The investigations did not identify any risk associated with the operation of the water supply systems and all investigatory samples taken in response to this breach including swabs collected from the individual samplers’ cool boxes were satisfactory.
Whilst an audit completed at the laboratory did not identify any deficiencies within current working practices nor within the laboratory environment, further analysis completed on the colonies recovered from the samples indicated that contamination may have been introduced at some stage during the sampling activity or present in the sampling bottle or within the laboratory environment. Whilst the company completed a satisfactory investigation it could not definitively identify a root cause of the event.
South East Water – Newnham
In February, South East Water also detected coliform bacteria in a sample taken from its Newnham works in Kent. The site is a groundwater site which abstracts from a chalk aquifer. In response, the company conducted an investigation which confirmed that the works process was operating correctly with disinfection being maintained, and all investigatory samples taken from the site, reservoirs, and customer properties were satisfactory. The site investigation found a minor leak on the sample tap but this was not considered contributory to the failure. The contact tank at Newnham works, last inspected in 2009, is subject to a legal notice (SEW-2025-00019) requiring removal from supply for inspection by June 2026. In the interim, the company conducted an ROV survey and enhanced monitoring remains in place.
Bristol Water – Banwell
Bristol Water also detected coliform bacteria at its Banwell works in February. In response, the company conducted a satisfactory investigation which included a site inspection, a sampling survey, inspection of air valves and it brought forward the inspection of the treated water tanks. The company identified that five days prior to this breach, a leak had occurred on the strategic main system which can feed a treated water supply to Banwell works, however it was determined that due to the operation of this system at the time, this could not have contributed to the detection. The company did not definitively find a cause for this detection however, in response, Bristol Water has selected Banwell works as the first site for a new Hazard Review (HazRev) process, aimed at identifying and mitigating any risks across its sites.
Anglian Water – Gainsborough Reservoir Total coliforms March 2025
An initial site inspection was carried out on 11 March following the breach, with a subsequent inspection carried out on 12 March. No issues or ingress points were identified from the onsite checks of the treatment process. The internal condition of the upstream treated water tanks at Everton works and upstream storage point Gringley Reservoir 3 (Large) West were not believed to be a cause of the coliform detection. The treated water tanks for Gainsborough are due to be inspected, but the condition is currently unknown, so could not be ruled out as a potential cause of the coliform detection.Enhanced sampling was set up week commencing 17 March 2025 to continue until the treated water tank inspections had been completed. At Gainsborough works, it was noted that disinfection occurs by free chlorination through contact time (Ct) in the low lift sump. At minimum tank level and maximum flow, the Ct through the low-level sump is 1.72 minutes. The treated water is then pumped to the onsite Gainsborough Reservoir, which under normal system configuration also receives a supplementary flow of treated water from Everton works via Gringley Reservoir 3 (Large). The regulatory final water sample tap for Gainsborough works is located on the gravity supply to Gainsborough Low Level Distribution Zone, and therefore after the water has been blended.
The company’s response stated that disinfection at Gainsborough works was verified on site in accordance with the SSDP with appropriate alarm levels which automatically shut the site down to ensure the Ct is met at all times. From the information provided by the company, it was concluded that the company was not meeting the requirements of regulation 26(2)(b) and was unable to verify the effectiveness of the disinfection process at Gainsborough works. A recommendation was given for the company to review the disinfection process at this works and provide a solution to ensure that disinfection is verified at all times.
Industry-wide learning:
Disinfection verification should include appropriate monitoring, recording, and validation arrangements to demonstrate full regulatory compliance.
Complaints
United Utilities March 2025
A consumer contacted the company via an email sent to the company’s Environmental Information Office regarding their water quality concerns on 30 November 2024. The email was forwarded to the water quality and public health team on 4 December 2024, and the consumer was contacted by the company on 5 December 2024. However, there were delays in the initial company response because the request was made via a Freedom of Information request, instead of via the contact centre. The consumer also received poor communication with the company throughout their experience including; not receiving an email because it was sent to the wrong address, not receiving call backs from the company, the use of an incorrect name and date in an official correspondence to the consumer, miscommunication about the company’s complaints procedure, and mismanagement of requests for information.
Another consumer contacted the company via email on 25 February 2025 which included their full name and address and the water quality concerns the consumer was experiencing. It was noted that this email should have been escalated to the water quality team for investigation, however, the company only attempted to contact the consumer following receipt of the complaint investigation from the Inspectorate on 3 March 2025. The consumer’s complaint was not escalated to the water quality team for investigation, and this again highlighted a gap in company processes and procedures.
Recommendations were given to the company on these two occasions for the company to undertake a review into the different methods by which consumers can contact it and put in place measures to ensure that water quality concerns are highlighted, prioritised and escalated for investigation in a timely manner.
Companies need to ensure there is a coordinated approach across different teams to quickly and effectively address water quality concerns, and to ensure these contacts are appropriately handled, in a suitable time-frame and informative responses are provided.