8:50am Tuesday 10th January 2012
By Kathryn Bradley
Visitors to Bingley’s world-famous Five Rise Locks will this month get a rare glimpse of parts of the engineering masterpiece normally hidden underwater.
British Waterways has drained the Grade I listed structure for maintenance revealing the bottom of the Leeds-Liverpool Canal and the impressive 23ft high brick walls that line it.
The work, which includes replacing four of the six gates on the 18th century structure to improve safety, is expected to cost £250,000 and is likely to take seven weeks to complete.
Peter Carter, construction supervisor for the Bingley lock gate replacement project, said: “Every time we get in to the bottom of the locks it is fascinating to see what our ancestors did.
“We are using hydraulic cranes to lift the gates but they just had A frames, block and tackles, shovels and picks. We are working on something that is part of our history and that is what me and the team love about it.”
The existing lock gates have been in place for 25 years. They will be replaced by new oak gates made at Stanley Ferry Workshop in Wakefield – one of only two lock gate workshops in the country.
The water is being kept out of the lock chamber while the gates are removed using stop planks laid on top of each other to form a watertight seal. This will also enable the team to carry out repairs to the lock chamber brickwork, using traditional lime mortar to preserve the heritage of the structure.
The towpath will be kept open during much of the maintenance but will be closed at short notice when the three-and-a-half tonne lock gates are removed and replaced using the giant cranes.
It will take two days to replace all four lock gates using two cranes located at the top and bottom of the flight of locks.
The cranes cost £4,000 per day to hire and are so heavy the towpath walls have been reinforced with 85 tonnes of stone ballast to take the weight. They are fitted with an instrument to measure wind speed and will shut down automatically if gusts get too strong.
To prevent water levels dropping further down the canal, a pump will feed eight mega-litres of water every day from the top end of the locks in to a by-wash, which flows in to the canal at the bottom of the lock and on to Leeds.
An open weekend will take place on January 28 and 29 from 10am to 3pm, when there will be a chance to descend deep into the lock to walk along the canal bottom and speak with British Waterways experts.
Mr Carter added: “These works usually happen on closed sites but we’re inviting local people to come and discover what’s going on at Bingley.
“It’s skilful work and the tours will give visitors an opportunity to learn more about what we do in winter to maintain good navigation for our boating customers.”
Bingley Five Rise Locks were built by John Longbotham and are one of the major landmarks of the national waterway network.
When completed in 1774, thousands gathered to watch the first boats make the 60 foot descent, which can take up to 90 minutes.
More than 200 years later, the flight is still in daily use providing access to 16 miles of lock-free cruising on the Leeds-Liverpool Canal.
e-mail: kathryn.bradley @telegraphandargus.co.uk
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