THE newly-restored swing bridge at Howsham Mill marks the latest step in its journey from mouldering mock-Gothic ruin to 21st century green electricity generation and education centre.

Amy-Jane Beer, trustee for the 18th century mill, said the bridge's completion is a cause for celebration. "Volunteers at Howsham Mill have good reason to be proud," she said.

"It's 13 years since Dave Mann and Mo MacLeod 'discovered' the mill and were inspired by the location and the unusual building."

This was in 2003. The pair liked the mill, which was originally designed by John Carr of York as a faux-Gothic garden folly, and saw its potential as a source of zero-carbon, renewable energy.

They formed the Renewable Heritage Trust to raise funds to spruce up the building and to install the means of generating hydroelectricity.

Their idea was to put in an Archimedean screw turbine - the very first to be installed in the UK. These structures use the concept of the Archimedean screw in reverse - the long turbine is turned by the force of rushing water, creating electricity.

Completed in 2009, the restored waterwheel and the screw turbine have been churning out up to 30 kilowatts of power – roughly the usage of a village the size of Howsham.

The restoration project was funded by a variety of different sources, including the heritage lottery fund, the BBC Restoration Village show - in which it was the regional winner - the country houses foundation, as well as Ryedale District Council and the Howardian Hills AONB.

By the end of 2013 the building work was finished and the mill began its other planned function, as an environmental education centre.

But there was just enough money left to complete one final piece in the jigsaw – the restoration of the swing bridge that once connected the island to the grounds of Howsham Hall and allowed horse drawn wagons to come and go between the mill and the local farms, delivering loads of grain, flour and animal feed.

In the early 1720s, the bridge was needed to cross a short canal which had been dug to bypass the weir after an Act of Parliament required the rivers to be navigable by large barges carrying goods such as corn, coal and stone.

Documents from the time record the specifications for the canal and the lock at Howsham, and also "a good and sufficient wood bridge over the said lock for horses to pass over the same to the mills".

By the early 19th century there were up to 20 barges a day using the canal, but as the railways were built, its usage fell and fell.

By the late 20th century, only the canal and lock survived. All that remained of the bridge were the stone footings and a large iron pintle on which the structure would have pivoted.

Trustee Martin Phillips said: "We all agreed that restoring the bridge would be a wonderful finishing touch for the Howsham Mill project.

"But with no pictures or detailed plans to give a clear idea what the original looked like, the team had to look elsewhere for design inspiration.

"And there was another challenge. There is normally no vehicle access to the island, but it was decided that the new bridge needed to be strong enough to take an emergency vehicle."

A number of local craftsmen and engineers were drafted in. Engineer Ed Green of TWS in Leavening constructed a substructure in steel which was then clad in traditional oak by woodsmith Adam Walker of Yorkshire Oak Frames in Wetherby.

The stonework was restored by Nawton-based Stephen Pickering.

"We're proud that the restoration has been such a local effort," Martin added. "All the contractors really engaged with the spirit of the project. The result is a new bridge that looks as though it has always been there."

The first public demonstration of the bridge in operation took place last month as part of the national Heritage Open Day event coordinated by English Heritage.

Howsham Mill is open to the public every Sunday from 11am. For more information, visit howshammill.org.uk