MANY readers will be concerned by the alarmist and misleading claims about polluted drinking water reported in the media.

I assure them categorically that there has been no sewage contamination and that the water in our region is of high quality and safe.

At no time has it been unfit to drink. Neither Mr Byatt, the Director General of Ofwat, nor the independent Drinking Water Inspector, has said there has been sewage contamination.

The statement is either a misunderstanding or a deliberate misrepresentation.

The true situation is this: we carry out comprehensive monitoring of bacteria levels in water to ensure that we can detect any possible sources of contamination before the water is in any way unsafe to drink.

These are standard tests, carried out world-wide, which detect certain types of bacteria as coliforms. They are very common bacteria which live all aound us, particularly in soil.

Faecal coliforms, which originate from the wastes of all animals, are fewer in number, but are still very widely present in the natural environment. They are, therefore, very sensitive tests to detect if, for instance, any soil has come in contact with our drinking water.

The detection of a single bacterium in these tests does not mean that water is unsafe, nor that there is sewage contamination.

It does indicate that water may not be up to its normal quality and that further investigation is required. In all cases, the reasons are fully investigated and action taken to ensure the water remains of the highest quality.

Occasionally, such bacteria are present even in properly treated drinking water. European Union regulations recognise this but lay down stringent standards.

Last year, North West Water carried out over 70,000 bacterial tests on the water supply and over 99.5 per cent did not contain a single coliform, with over 99.9 per cent without a single faecal coliform. This proves its excellent quality.

ERIC HARPER, Quality Regulation Director, North West Water Ltd, Warrington.

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