Gardeners whose allotments have been flooded for months are now being asked to pay a £100 bill for water they could not possibly have used.

Not only have they had rain in abundance since last autumn, piped water to the site is always turned off over winter to prevent damage to frozen pipes.

The Osney St Thomas and New Botley Allotments Association, in Oxford, is refusing to pay the quarterly estimate, and has told Thames Water to do its sums properly.

Treasurer Fred Poore, who lives just a few minutes' walk from his allotment in west Oxford, said he found it disconcerting that his association never received regular bills, as a domestic user would.

Mr Poore, 82, said: "There is not a shadow of doubt I shall not being paying this bill.

"The whole site - apart from 12 allotments - was flooded for quite a long period. Anyway, the supply is not restarted until the end of March.

"It does surprise me that they don't have a system for adjusting accounts and basing their estimates on previous bills. Why didn't someone realise ours was going to be virtually nil during this period?

"It does seem ridiculous to send us an estimate for £100 for water we never use."

A spokesman for Thames Water said they appeared to have over-estimated the amount of water used.

"We can understand the allotment users' puzzlement, and are sorry for any confusion the bill may have caused."

He said a meter reading would be taken and a new bill issued. The latest estimate would be cancelled.

The spokesman said that, normally, bills should arrive on a quarterly basis, but if postal codes changed, or if there was a significant change in the number of meters in an area, bills were re-allocated to a different reading which sometimes meant bills were sent out at different times.