DRINKING water quality in the St Albans and Harpenden area - contaminated by the cryptosporidium bug three years ago - is the best it has ever been, say government inspectors.

The Drinking Water Inspectorate's report on the area supplied by Three Valleys Water says some 99.82 per cent of 71,400 tests carried out in 1999 complied with both national and European standards.

Tests were carried out for a range of impurities, including bacteria, lead, iron and manganese and were found to be within health guidelines.

Anglia region inspector Malcolm Morgan said mandatory testing for the cryptosporidium bug, which came into force following an outbreak in north London and St Albans in March 1997, had been of benefit.

The bug can serious stomach upsets and diarrhoea.

Mr Morgan said: 'Mandatory testing is ensuring that water companies take early action and risks to public health are kept to a minimum. Early results confirm the benefits of having these new regulations.'

Three Valleys Water has to carry out daily checks for the bug.

The cryptosporidium outbreak in 1997 affected 300,000 homes in the north London area including St Albans.

For 16 days, householders were told to boil their water following a bug outbreak in boreholes in the Colne Valley. Households affected received £10 each in compensation.

tThree Valleys Water has reported increased profit before tax of £48.5m in the year ended March 31, 2000, up from £39.2m in the previous 12 month period. In the same period its turnover increased from £138.2m to £146.7m.

This year, customers are to receive a £20 reduction in their water bills.