99.85% compliance with drinking water standards

Tuesday 20 October 2020

Guernsey Water has achieved over 99% compliance with all water quality standards, with only 11 complaints made by customers last year.

The figures, published in the company’s 2019 Water Quality Report, show that key performance indicators – compliance with maximum admissible concentrations at its three treatment works, three service reservoirs and customer taps in two water supply zones – have all been achieved at a rate of 99% or above.

Water Quality Risk Manager for Guernsey Water, Margaret McGuinness, said 7,475 laboratory tests have been conducted over the last calendar year. 

"Supplying water that is safe and good to drink is always our top priority. This has become ever more important in the face of significant challenges to water supplies from climate change, and of course, the events of the past six months," she said. 

“It is important to us that customers trust that our drinking water meets the highest standard. To achieve this, we invest in efficient, sustainable water treatment to improve the quality of our water.”

Pictured: Guernsey Water's annual report for 2019 can be read in full HERE.

During 2019, the company regularly tested for a wide range of pesticides and of these, only 32 were detected and one breach of the 0.1ug/I limit observed, which was due to a pollution incident at Kings Mills.

Streams across the island are regularly monitored for the presence of glyphosate, which is one of the most widely used pesticides and remains a concern, so checks ensure that the levels found are of no challenge to the water treatment processes.

Compliance with bacterial standards at the island’s three service reservoirs was slightly lower than in 2018 at 99.23%, due to three low-level bacterial detections at the service reservoirs at Forest Road.

There were a total of 11 water quality complaints from customers in 2019, the majority of which were about 'taste' and 'odour'.