Drinking water quality continues to improve in England and Wales

Drinking Water 1998 summarises the level of compliance with drinking water regulations achieved by the 28 water companies operating in England and Wales. Overall, compliance continued to improve in 1998 with pesticide levels compliance and the microbiological quality of water at treatment works and service reservoirs improving substantially.

According to the report: “Pesticides compliance has improved from being the parameter responsible for the largest number of contraventions of the standards in 1995, individual pesticides in 1998 now breached the standards on fewer occasions than eight other parameters, six of which have themselves showed significant reductions.”

The report also comments on the presence of polycyclic aromatic hydrocarbons (PAH), chemicals involved in the combustion of fossil fuels. “The steady rise in the number of zones not complying with the standard for PAH, which was apparent from 1991 to 1996, was reversed in 1997 and the downward trend has continued in 1998,” the report states.

Four companies are shown to have improved the quality of drinking water they provided to customers in 1998. They are: Essex and Suffolk, Severn Trent, Thames and Yorkshire. Northumbrian Water showed a “statistically significantly” deteriorating trend in overall water quality, and the remaining companies showed no statistically significant trend either way.

One area of concern highlighted by the DWI’s 1998 report were the increasing incidences of discoloured water being provided to customers. Although such water does not pose a threat to human health its colour is unacceptable.