This summer is the hottest recorded summer, going back to records starting in 1994, according to the Met Office. This has meant that incoming mains water is getting over the recommended temperature of 20°C. The Water Supply (Water Quality) Regulations state that water can be supplied up to 25°C. If you are finding water being supplied above 25°C, you should notify your supplier, and they must investigate and work to remedy the high water temperature. As Legionella is a naturally occurring bacteria, it can’t be totally removed from a system, so management of the water system is crucial.
The main issue with this is that water is being supplied at 25°C well within the Legionella growth band (20°C-50°C) and can compromise the bacterial control within a cold water system. During these periods of warmer weather, managing your cold water system can become a lot more complicated, as you must rely on other control measures to maintain control of the water system. The main control measure during this time will be turnover of the system, making sure that there is no stagnant water that can promote the bacterial growth.
Recently, there has been a Legionella disease outbreak in Kimberworth Park area, Rotherham. The outbreak was identified when a higher than usual number of Legionnaires disease cases were reported within the month.
Rotherham Borough council working with UK Health security agency NHS partners to investigate the source of the bacteria, and currently it is unknown why there has been an increase in cases, but the hot weather is a strong contender.
A spokesperson from Yorkshire Water told the Rotherham Advertiser that, “Some of these cases may be isolated incidents with no common source, however we are working to identify any links between cases and potential common sources for public health action.” Outbreak of Legionnaires Disease in Rotherham - but public told not to panic