Lock of ages

WHEN the tide turns, the River Ouse at Selby turns back on itself. The current flows as swift and strong as ever - but it's backward up towards York, not out to sea. From the mouth of the Selby canal it's an awe-inspiring sight.

At low tide the river level can be 15 feet or more lower than at high tide. When the flood tide first begins, the river's at its lowest ebb, revealing high mud banks on either side. You can smell the wet, muddy scent of river. Then as the tide turns a surge of muddy water rushes upstream, ever swifter. You can feel the power of the river, like a living thing.

Because the Selby canal empties into a tidal river, navigating the lock that links the two can be tricky. The Selby canal, completed in 1778, links up with the Aire and Calder navigation and with the New Junction Canal, which leads down towards Doncaster and the heart of England. Then of course there's the Ouse, which leads to the Humber and up to Naburn and York.

Despite being at the confluence of so many waterways the great days of Selby as a busy port are long gone. Cargoes of rice imported through Hull unload a couple of times a week, bound for the town's flour mill. Otherwise, the wharves lining the Ouse are mainly silent.

The canal itself, says lock keeper Fred Firth, is now used by pleasure craft only. In the busy summer months - especially on a Bank Holiday weekend - there can be up to 25 craft, narrowboats and cruisers, negotiating the lock from canal to river, river to canal.

It's not like just pulling onto the M1 at Junction 41, though. The tides wait for no man. "We have to wait for the tide to be right," says Fred, standing on the lock gates and looking at the swift surge of the muddy Ouse 15 feet below.

For boats leaving the canal and heading upstream to York, that means waiting until the ebb tide turns to flood, and the current reverses to flow back upstream. That's when the river is at its lowest: meaning a lot of water to be pumped out of the lock.

Judging the right moment to let boats through comes with experience, says Fred. For cruisers - fast, powerful, easily manoeuvrable boats - the best time is half an hour after the tide has turned. At low tide, water levels in the Ouse can be low. The boats need the extra depth given by half an hour of incoming tide as they travel upstream. Otherwise, because of their speed, they risk outrunning the tide and encountering shallow water.

For narrowboats, it is different. They're slower, clumsier and less manoeuvrable than cruisers. Because of the speed of the current as the incoming tide picks up, it is better to let them out earlier. "We let them out as soon as the tide starts to turn," says Fred.

The power of the river is soon obvious when the Pax, a 29ft cruiser crewed by Tony and Christine Baldock, leaves the lock and sets off upriver for Naburn.

The Baldocks, from Copmanthorpe, spent the night moored in the 'basin' behind the Selby lock, waiting for the morning and the flood tide. For the last week they and the Pax have been touring the New Junction Canal towards Doncaster.

"It's the most peaceful way I know of getting away from the hustle and bustle," Tony says cheerfully, standing on the deck of the Pax as it is 'penned' in the lock. "If you want to you can go from pub to pub, or you can tie up in the middle of nowhere and have the place to yourself." The lock gates close, and the Pax sinks gracefully lower and lower as water is pumped out, until I'm looking down on the top of Tony's head. "And if you like wildlife, it's wonderful. There are kingfishers, herons, mink, water rats..."

Once the water level in the lock matches that of the Ouse outside, Fred opens the outer lock gates. The Pax moves slowly out, and is quickly caught up in the powerful surge of the current, swept away towards the railway bridge and swing bridge visible further upriver.

Tony is clearly in control of the Pax; but not all skippers are. Fred remembers one incident when a 50ft narrowboat was swept by the force of the current into a tree blocking one arch of the swing bridge soon after it had left the lock.

The fire brigade had to lower a ladder to get everybody except the skipper off the boat - and then the tree had to be cut away before the boat could move. Thankfully, no one was hurt.

Another time, a cruiser had come up the Ouse from Hull. It was waiting in the river for the lock gates to open.

"The man's wife went down below to make a cup of tea, and she saw all this water," Fred recalls. "The boat was sinking in the water." The boat's skipper pulled over towards the lock gates: but then the waterlogged engines cut out. Onlookers were enlisted to help tug the boat into the lock. Everybody was pulled off, and Fred managed to get the boat through the lock and up into the shelter of the basin: where it promptly sank. It was holed, the theory goes, by a large piece of debris being swept down the river.

There have been one or two incidents like that in Fred's five years in charge of the lock - one time an elderly man fell overboard while his boat and several others were in the lock together. He got wedged between boat and lock wall and Fred had to climb down to free him - but generally, Fred says, accidents are few and far between.

Often, inexpert boatsmen call upon his experience to help them through the lock. "Some people like to be guided in if it's their first time," he says. "The hardest thing about this lock is if you have a boat coming in on the ebb tide. They're pushing against the tide: but there's a slack area in the river just outside the lock entrance.

Some people come in too quickly pushing against the tide, get into the slack water, and are pushed forward. I've had a few bows bumping the gates, though nothing serious."

It's because the lock is so tricky that a lock-keeper will probably always be needed.

The gates themselves were mechanised a year and a half ago - until then, they had to be opened manually.

But there's not a lock mechanism going that can judge when the tide's just right for a boat to slip out of the lock onto the swift, muddy waters of the Ouse.

PICTURE - Lock-keeper Fred Firth keeps a watchful on the river level at Selby lock

Pictures: Paul Baker