WEST of Scotland Water last night defended itself against a fierce deluge of criticism of its handling of a contamination scare which has left 60,000 people without safe drinking water.

The authority said it would be several days before it could restore safe supplies to the affected areas in Milngavie, Bearsden, Clydebank and Faifley, after an unknown amount of diesel entered the supply system at the Burncrooks treatment works at Drymen.

Dozens of schools have been closed until further notice and about 16,000 households are being supplied by mobile tanks with water which has to be boiled before being drunk. Police officers and the members of the 3rd Battalion Royal Highland Fusiliers, from the Territorial Army's infantry battalion in Glasgow, have joined water workers to help distribute drinking water to the affected areas. Businesses, particularly those needing water to prepare food, have also been severely affected by the contamination.

The criticism was led by local Labour MP Tony Worthington who condemned the authority's ''appalling communication and slow action'' and said he would ask Scottish Secretary Donald Dewar to hold a public inquiry.

He said: ''This shows the danger of quangos who fail to answer to the public. The company has been very slow to pick up the problem and take action.

''People have told me of a strange turpentine-like smell around their homes as much as a week ago and had suspicions of the water supply.

''The telephone lines are totally engaged and I have found it impossible to get through to ask for accurate information. The company was warned about this two years ago at Christmas during the freeze when its telephone lines were unable to cope.

''It is a very serious matter when people cannot use the public water supply. It is still unclear precisely which areas are affected. The information given out is inconsistent and still this morning some households have not been leafleted. A major breakdown has occurred and WSW has failed to account for its actions.''

The Scottish Water and Sewerage Customers Council also called for an inquiry. ''We believe this situation is sufficiently serious to warrant the most rigorous public examination,'' chairman Dick Douglas said.

They were supported by irate residents in the affected areas. Mrs Alison Galpin, of Bearsden, said she had alerted WSW at 8.30am on Wednesday. ''They said they would take a sample but didn't. I called them six times asking them to put leaflets through people's doors. At 6pm they told me it only affected 10,000 people and was not a significant problem. They are completely irresponsible.''

She added that she had sent a sample for independent analysis and was considering legal action.

At a highly-charged news conference, it fell to Mr Charles Schooling, WSW customer services director, to defend the authority's actions.

He said: ''The first indications we had were at 10am and were taste complaints. These built up as the morning went on. It was early afternoon when we got a significant number of complaints that pushed us into the emergency action that we have been taking.

''We get taste complaints every day. It is not until you get a significant number in one supply zone that you appreciate there is a problem. It would be wrong of us to jump to conclusions, it is a difficult judgment to make.''

He said they had got information out by 5pm on radio and TV. He said the diesel pollution had been traced to the Burncrooks treatment works at Drymen, near Loch Lomond. However he did not have the full details.

''It could have just been a slug of contamination. The water coming down after that could have been unaffected. It is equally important for us not to disrupt customers' supplies unnecessarily. We suspect a spillage but again that all needs to be confirmed by investigation.''

He added: ''There is a lot of plant and equipment that could be the source. We want absolute facts before we can comment. However we are probably dealing with a relatively small quantity.''

Responding to Mr Worthington's criticisms, he said: ''I think as customer services director I would never ever be satisfied with communications on incidents like this. It's virtually impossible for us to suddenly step up the number of telephone lines to satisfy the number of calls. We've increased the number of lines from December, 1996 - that has trebled. We are trying to answer calls as quickly as possible.'' He said that during a three-hour period on Wednesday night, they had been deluged with 5000 telephone calls.

The authority disputed that people getting through had not been offered proper advice. ''All people answering calls had adequate information to deal with questions.'' Mr Schooling said Mr Worthington's call for a public inquiry was ''an understandable reaction''.

He added: ''I hope we will get a more balanced view of the action we took. I can't deny we would like to be able to work faster, reassure people quicker and resolve the problem faster. At the end of the day you can only do the best that you can and have the proper plans in place and make sure they work.

''We learn from these incidents every time they occur.'' He said it would be a few days before the water would be restored.

''It depends on the investigation going on. The treatment works is a large, complex place. We need to isolate the source firmly. It will take time to clean up the whole works.''

A WSW spokesman added that because of the large area involved and the high numbers of customers affected, the topping-up of tankers would take time. ''The authority is asking customers to be patient in the circumstances and fresh supplies will eventually arrive. Tap water should be used only for flushing toilets. Water drawn from the containers should be used for drinking, cooking, and hygiene purposes but must be boiled first.

''Special-needs customers, such as those on home dialysis machines and others with disabilities, are being assured that fresh water supplies will be supplied.''

The affected areas in Milngavie are: Craigton, Mugdock and Hunter roads, Mains Estate and Barloch. In Bearsden: Duntocher and Stockiemuir roads, Baljaffray, Castlehill, Thorn area, Bonnaughton, Mosshead, Kilmardinny, and St Andrews College. In Clydebank: Drumry, Duntocher, Hardgate, Dalmuir, HCI, Parkhall, Kilbowie, Whitecrook. Two other areas affected are Faifley and Mosshill.