On The Waterways appeared in The People’s Friend Special

“Every time someone opens these lock gates,” says Mike, the engineer, “we lose 40,000 gallons of water.”

We’re standing at the bottom of Lock 72 of the Trent & Mersey Canal in Middlewich, Cheshire, thanks to one of the Canal and River Trust’s Open Days.

Every winter a team of engineers and volunteers repair, maintain and service some of the 2,000 miles of waterways the Trust is responsible for in England and Wales. This winter, the Trust are overhauling 164 lock gates, of which Lock 72 is one.

Behind me, a temporary dam of wooden planks holds back most of the canal water, and a small pump extracts any sneaky seepages that drip through. I keep looking over my shoulder to check it’s still working!

It’s a privilege to stand down here, on bricks that were first laid over 240 years ago. The 93 ½-mile long Trent and Mersey Canal was built in 1776 to link the River Trent near Shardlow with the River Mersey near Ellesmere Port.

One of the canal’s main promotors was Josiah Wedgwood, founder of the famous Wedgwood pottery business. He was keen to get his precious bone china to markets, avoiding as many bumpy roads as possible, while also finding new ways of transporting his heavy raw material – clay – to his potteries in Stoke-on-Trent. The canal gave him easy access to Liverpool, one of Britain’s busiest ports.

The bricks we’re standing on look like typical clay house bricks, but the main walls of the locks are built from much larger stones. Mike points to some at the bottom of the lock.

“They’re not cemented together,” he says. “Instead, they’re held together with lime mortar. And the only way to get lime mortar to harden in those days was to used crushed bone china.”

It seems Josiah Wedgwood found some use for all those broken pottery pieces shattered on Britain’s bumpy roads!

“All these stones have a mark,” Mike explains, “called a mason’s mark. Each mason had his own mark, and at the end of the day the boss would come round and count how many stones each mason had made that day, and that’s how they were paid.”

Canals use locks to negotiate hills, allowing boats to rise or fall to different heights. All canal locks have two sets of gates – a smaller pair at the lock’s highest point, and a taller pair at the bottom.

Each of Lock 72’s big wooden gates weighs 1,591kg. Mike pulls one open with one hand. It’s that easy when there’s no water to hold back!

“Each pair of lock gates usually lasts 25 years. These particular gates are 23 years old and are made from the English Oak species,” says Mike, before giving us the punchline, “which is grown in France!”

No two lock gates are identical. Each is bespoke, individually shaped to produce a water-tight fit.

Mike points to a tin of red paint. “We can’t fill the lock with water to find where the new gates leak, because we’d waste so much. So we spread red paint along the quoin, the edge of the lock, and then we close the gates. When we open them again we get spots of red paint on the gate. These tell us where the high points are. We plane those off, put more paint on and repeat the process. We keep doing that until we get a continuous line of red paint on the quoin. Then we know we have a watertight seal.”

Clever! And how do the lock gates get here? They come by canal boat, of course, which saves clogging up the roads.

“How many shopping trolleys did you find in here?” a visitor asks.

Mike chuckles. “Actually, in here there were none. The most common things we find at the bottom of the canals are cameras. Holidaymakers often drop their cameras into the water.”

It’s not just cameras they find at the bottom of these locks. There is a collection of windlasses, metal keys that holidaymakers use to open and close the locks, at Mike’s feet. “There are two boat hire companies here,” Mike explains. “This is the first lock many of the holidaymakers encounter, so it’s their first attempt at opening or closing a lock. One slip and they lose a windlass straight to the bottom!”

Mike pats the huge foundation stones again. “Sadly, in the water, the only things that see these wonderful stones are the fish and whatever else gets dropped in. But the workmanship on these stones down here is just as good as that on the bricks everyone sees at the top.”

As we climb the steps back to ground level, one thing is clear. The old adage is certainly true. They don’t build things like they used to. And I’m glad that temporary wooden dam held out while we were down here too. But then, it is a 200-year-old technique they’ve successfully used for maintaining canals. Which just proves that, sometimes, the old methods are still the best methods!

John Sidley, Canal & River Trust Volunteer

John Sidley began volunteering for the Canal & River Trust about two years ago, and helps out a couple of days every week. “It gets me out of the house, and I feel I’m doing something good. I was in engineering when I was working, and it just fascinates me how the builders overcame obstacles without the technology we have today. I love working on the locks, and usually work on Lock 43 at Red Bull. You meet some lovely people, especially in summer. Last summer I met people from South Africa, Australia, New Zealand and Canada. They love the history of our canals.”

© Simon Whaley