Slurry detected in drinking water in Waterford town

A boil water notice was issued in a small Waterford town after slurry was detected in the drinking water supply.

Discoloured water, from an old disused spring, had leaked into a treated water reservoir in Kilmacthomas.

The Environmental Protection Agency (EPA) conducted an audit of the town’s public water supply when a complaint was made about the taste of the water.

Concerns about the supply had been triggered on February 14.

An EPA report, published this week, said water from the spring was observed to be discoloured and a smell of slurry was detected within a treated water tank.

Chlorine levels used to treat drinking water were also recorded as four times lower than normal.

A precautionary boil water notice was issued on February 15 but lifted before the end of the day after the reservoir was cleaned and scoured.

Tests for cryptosporidium conducted the following day were negative.

However, the EPA said the leakage was of “significant concern to the health of consumers”.

Although the supply’s caretaker responded quickly to rectify the situation, the EPA said there had still been a delay of 30 minutes where contaminated water was potentially getting into the town’s water supply

The Kilmacthomas supply provides 155 cubic metres of drinking water to a population of more than 550, with water sourced from three main springs.

The EPA audit found the Kilmacthomas scheme was at risk of contaminated water entering the public water supply because there are no automatic shutdowns in place when low chlorine levels are detected in treated water.

The EPA called on Irish Water to fast-track the installation of an automatic shutdown to prevent any future contamination.

Inspectors claimed the current location of the sampling point for chlorine in treated water was not reliable or consistent because it was too close to the point where it was added to the supply.

Irish Water was advised to relocate the chlorine sampling point as soon as possible.

It had emerged slurry had been spread on a field adjacent to the disused spring.

The EPA also recommended Irish Water liaise with the local council to ensure organic fertiliser or soiled water should not be applied to land within 200m of a drinking water source. In relation to farmyard manure, the limit is 250m.

EPA inspectors noted the connection between the disused spring and the treated water reservoir had been severed and, as a result, the risk of further contamination from the same source had been eliminated.

Meanwhile, in Innishannon, Co Cork, an audit of a supply which provides drinking water to more than 21,500 people revealed that giardia — a parasite that can cause diarrhoea — was detected in treated water last September.

Irish Water was unable to identify the source of the contamination. Subsequent monthly tests found no other traces of giardia or cryptosporidium.