Talks are today going on over the 11th hour cancellation of the Wayland Agricultural Show at Watton.

The bitterly-disappointed chairman has warned the enforced decision because of a sewage spill could jeopardise the whole future of one of Norfolk's best-loved countryside spectaculars.

Organisers of the 139th show, which had been all set to open yesterday morning, called off the whole event with only hours to spare after raw sewage flowed on to the showground site when lightning put a nearby Anglian Water pumping station out of action.

Exhibitors, stallholders and farming families drawn from far and wide had been making the final preparations to welcome hordes of showgoers when disaster struck. Last year's attendance of 15,000 set a record, and the show team was expecting to match or even top that figure at what is one of the oldest one-day agricultural shows in Britain.

Show committee chairman Graham Shingfield said the extent of the leakage was discovered at about 6.15pm on Saturday and the decision to cancel was taken shortly afterwards.

He added: 'I am devastated –absolutely devastated. It is soul-destroying, to be honest, that we have had to do this through absolutely no fault of our own.

'It is going to cost us thousands and thousands and thousands of pounds – it could break our show. We cannot insure against risks like this.'

He added: 'There is no way we will be able to give any money away to local charities this year. That is always something we have endeavoured to do because it is part of our remit.'

Mr Shingfield, of Manson Green Farm, near Hingham, said the crisis unfolded after the show team and some of the 40-plus band of volunteer helpers realised the gateways to the Brandon Road showground were getting very wet.

'Then someone said: 'Look where it is coming from'. The stuff was going in the ditches and it was getting everywhere,' he added. 'It was like a river.'

Mr Shingfield said the water company had an engineer on site quite quickly but the effluent had contaminated about an acre and there was no alternative but to call off the event.

Wayland Show organisers toiled through Saturday evening trying to let everyone involved know of the cancellation decision. And yesterday, the show team and exhibitors faced a logistical nightmare trying to clear the showground of marquees, animal pens and stands without risk to their health. Mr Shingfield said they cordoned off the affected land and were using a second entrance to remove vehicles and equipment. Hand gel was being made available to help avoid the danger of infection.

Asked if Wayland Show would seek compensation from Anglian Water, he said: 'We shall have dialogue with them – we want to talk to them. But we are very cross.'

He said one showgoer he had spoken to yesterday morning had driven overnight from Blackpool only to discover the event was off.

Many families planning to visit the show to enjoy livestock and equestrian events, cookery and lifestyle displays and grand ring attractions had booked online. Asking them to check out the website www.waylandshow.com in the days ahead, Mr Shingfield said: 'We shall endeavour to refund people as soon as possible.'

He added: 'Next year was going to be our 140th year and we were going to have a celebration. Hopefully, we still will be able to. But obviously for now we are just upset and annoyed.'

Anglian Water spokesman Carly Millership said an electrical storm tripped out the pumping station, putting it out of action for about an hour and a quarter.

The downpour, plus the build-up of effluent from the station, had contributed to the leakage. Most of the outflowing sewage ended up in ditches adjoining the Anglian Water installation and showground.

She said an engineer and team were on the scene from about 7.45pm on Saturday pumping out and removing the effluent by tanker. They had completed the operation shortly after midnight yesterday.

Ms Millership yesterday apologised for the problems the spillage had caused but said unduly bad weather such as the electric storm that had affected Watton on the eve of Wayland Show could create problems. She added: 'All we can do is make sure, as we did last night, that we are on site as quickly as possible to resolve the issue.'

Of the prospect of compensating the show, she said: 'From our point of view it is too early to take that decision. We shall obviously be having discussions with the event organisers.'

Ms Millership said there had been no threat of contamination to local water supplies nor to the Cranswick food processing plant near the showground.