The Kennet and Avon Canal Trust has to move out of the canal centre on Devizes Wharf or face repairs amounting to £500,000.

The Wharf Centre, thought to be 200 years old, houses the trust museum and shop but has been suffering structural problems for some time.

Just before last year’s Devizes to Westminster canoe race, one of the toilets fell through a rotten floor, which cost nearly £20,000 to repair.

A beam had to be propped up after a crack was discovered and a five-yearly inspection revealed the wiring did not comply with regulations and needs £10,000 to put right. The heating system needs new radiators and boiler.

Possibly most seriously, the back wall facing Couch Lane is deteriorating, with pointing missing, stones falling out and light visible through it at one point.

Trustee Mike Rodd said: “The bottom line is that it is costing the trust £40,000 a year to maintain the building, money we can’t afford.

“But that is a small part of the picture.

“It would cost close to half a million pounds to completely renovate the building, and funding for that kind of work is hard to find.”

He said that the trust may have to leave Devizes, where it has been since 1982.

He said: “We have to face reality. We must get out of here and we have said we will leave by the end of September.”

A spokesman for Wiltshire Council, which lets the building to the trust, said discussions with the trust are continuing.

He added: “We are sympathetic to their position and hopefully we can come to some agreement.”