WORK is forging ahead to fill a hole the size of 12 double decker buses and reopen a historic canal in time for the boating season.
An enormous £2.1 million project to repair the 235-year-old Trent and Mersey Canal has started after a dramatic landslide in September left a gaping chasm in the Northwich countryside and filled farmers’ fields with around 29 million litres of canal water.
The breach happened in a remote location near Dutton, leaving the Canal and River Trust with months of work to negotiate and build access to the site for heavy machinery and the 12,000 tonnes of stones and other material needed for repairs.
Extensive investigation into how the incident happened has also been carried out.
Paul Brown, project manager, said: “There was heavy rain, a lot of ground water and a very sandy embankment – as water flowed through it became like a sand castle and started to wash away, the embankment gave up and the canal couldn’t hold itself up.”
Measures are being put in place throughout the repair work to help prevent it from happening again.
Paul said: “First of all we’re putting a land drain in at the base of the embankment which will take the ground water away.
“We’ll build the canal base up using layers of thick stone, which is very free draining – not like sand – and the water will just wash through that.
“It will then be built up in layers with a membrane so that it doesn’t move around and a waterproof clay-based liner.”
The liner, called bentonite geomembrane, is a flexible waterproof mat that will re-line and seal the canal.
The technology is a far cry from how the 18th century canal would have been built originally.
“Back in the olden days they compacted stone using cattle,” Paul said.
“Then when they put clay on top they used cattle again in a process called puddling – the hooves walking over it would compact the clay and knit it togther.”
The machine they use for this part of the process today pays homage to the old methods as it is called a sheepsfoot roller.
This was the first major emergency faced by the trust since it was made into a charity, and repair work has been made possible thanks to donations from the public in an appeal that is still ongoing.
The trust aims to reopen the canal in May.
Paul said: “It’s all weather dependent but we can make good progress now.
“Hopefully we’ve had the worst with the snow but we dealt with that quite easily.”
Interest in the project has been high and an open weekend has been organised for members of the public to view the breach and speak to engineers.
The event will take place on February 23 and 24.
It is free but ticketed as it is restricted to 30 people per hour.
For more information visit trentandmerseyopenweekend.eventbrite.co.uk.
• To support the emergency appeal visit canalandrivertrust.org.uk/breach or text BREACH to 70800 to give £5.