THE LONG-AWAITED £20m redevelopment of the Castle Mill Boatyard in Jericho has been thrown into doubt after it was a revealed a second bridge, added after drawn-out discussion with the community, could cost up to £500,000.

Planning consent has finally been granted for the scheme which would see a ‘piazza’ created between St Barnabas Church and the Oxford Canal, but the developer said new costings to take amendments into account could scupper the scheme in its current form.

Johnny Sandelson, the developer behind the scheme, which would be bordered by a community centre, boatyard, nursery, restaurant and 22 homes said at the very least the re-think would delay any construction on the site until after the summer.

The chief executive of developers SIAHAF said: "The boatyard has to be profitable for it to work and there have been an awful lot of demands placed on us since we started and we have to see if the viability is still enough.

"There's certainly a concern it might not work, but we have always been able to find a compromise so far and we hope to do so again.

"We are in the process of re-doing our costings, they have made some extra amendments, for instance we have to install a new bridge and that could cost anywhere up to £500,000.

He added: "If you were building an extension to the back of your house and you were suddenly told it will cost an extra £20,000, you would have a re-think about whether you could afford it or whether you should hold off."

Original plans, approved by Oxford City Council in February last year, had only included a bridge for pedestrians and cyclists at the end of Great Clarendon Street.

But changes put forward to include a second bridge over the canal directly into the proposed square were put forward following drawn-out discussions involving community group the Jericho Wharf Trust.

Last month marked ten years since police and bailiffs evicted boaters from the site for it to be sold to make way for housing.

Mr Sandelson, who remained confident of a positive outcome, said: "It has been painful, I have recently been involved with a project for 3,000 homes and we have built more homes in six months than has been done on the Jericho Boatyard in years.

"There is a quiet optimism that the scheme on the table will work, now that the section 106 has been signed.

"There is a will on both sides and it's a great site in a great location - we own the land and it will be developed, we just need to wait for the outcome of the costings."

Oxford City Council published planning guidelines for the site in December 2013 which outlined the importance of a bridge linking the canal and the development.

The Supplementary Planning Document also required a "new sustainably sized community centre" on the site.

Jericho Wharf Trust chairwoman Phyllis Starkey said the developer had known from the beginning what the requirements of the scheme were and had no cause to complain more than two years later.

She said: "From the off it has been very clear - through the council's supplementary planning document - what would be required of any potential developer.

"There were relatively high obligations on the developer but my understanding is as a result the land was fairly cheap.

"The developer therefore has no excuse and no reason to complain."

The Trust hopes to own and run the boatyard and community centre once the scheme is completed but needs to secure the land from Mr Sandelson.

Mrs Starkey said: "The planning permission and the section 106 agreement are obviously good news but we would like to meet the developer to finalise the transfer agreement.

"It's been an incredibly frustrating process and we want to get it sorted."