Scottish Water Convicted of Drinking Water Offence

The offence occurred in 2009, when Scottish Water inadvertently overdosed sodium carbonate into the water supply at Blairnamarrow treatment works, and failed to fix the problem for several days. Consumers in Tomintoul report an unpleasant smell and feel to the water and some said that bathing in the water caused skin irritation. Sodium carbonate is used in the water industry to correct the pH of the water. Samples taken and analysed by Scottish Water showed that the water was very alkaline, with pH readings in excess of 11. The Water Supply (Water Quality)(Scotland) Regulations 2001 specify an acceptable range between 6.5 and 9.5.

Once Scottish Water realised the scale of the incident, a “Do Not Use” notice was issued, resulting in the closure of a number of local businesses. The Drinking Water Quality Regulator (DWQR) investigated the incident and prepared the case for prosecution to put before the Procurator Fiscal. The conviction marks the first against Scottish Water for a drinking water offence since the company was created in 2002.

Sue Petch, Drinking Water Quality Regulator for Scotland, said:

“We are fortunate in Scotland to have drinking water that is of extremely high quality, and incidents of this severity are very rare. This case was the result of a number of factors that combined to cause an extremely serious water quality incident.

Scottish Water’s treatment works at Blairnamarrow, that serves Tomintoul, was not up to modern standards and did not have the safeguards we expect. This, combined with a wholly inadequate operational response from Scottish Water, produced an incident that caused great inconvenience to the residents and businesses in Tomintoul over a number of days.

The preparation of a case for prosecution is always a last resort for DWQR, and I sincerely hope that this case provides a clear message to Scottish Water of the seriousness of its responsibilities in protecting public health”.

Scottish Water has been prosecuted for the offence of supplying water unfit for human consumption under Section 76C of the Water (Scotland) Act 1980. Since the incident the company has built an entirely new treatment works to supply Tomintoul, and operational procedures have been considerably improved.

DWQR's assessment of the incident may be found here.