Why sharing a lock rewards a little planning

Most locks on the British network were built for working boats, and many of them will take two narrowboats abreast with room to spare. Sharing saves water, saves time and halves the work — but only when everyone involved has a rough idea of what everyone else is doing. A shared lock that goes well feels almost effortless. One that goes badly involves scraped paint, frayed ropes and a lot of unnecessary shouting across the water.

The good news is that the skills are simple, and the sort of boater who is easy to share a lock with is always in demand. It comes down to three things: talking before you act, keeping the boat where it needs to be, and not rushing the water.

Talk first, then work the lock

As you approach a lock, slow right down and read the situation. Is a boat already working it, with gates open and paddles up? Are two boats waiting? Is somebody walking up with a windlass? If you want to share, hail them early, while there's still distance between you. Ask whether they're going your way, whether they'd mind sharing, and how many of them are aboard.

Agree the jobs out loud before anyone touches a paddle. Something as simple as "I'll work the ground paddles, you hold your centre line and watch your bow" prevents most of the confusion that follows. Keep instructions short and specific. If you're at the helm and your crew is ashore, settle on a small vocabulary in advance — "hold her" should mean keep her against the wall, not let go. Hand signals work well at distance, as do nods, but they need deciding before the noise of rushing water makes talking hard.

Keeping your boat close to the bank

Come into the lock slowly, on tickover, aiming to bring the bow within a foot or so of the wall rather than a yard. Keep the stern in too, particularly in a narrow lock: a boat that has drifted diagonally across can catch on a gate as the lock empties, and that is how gates get damaged.

Use a centre line taken around a bollard or a lock ladder to hold the boat in, with the engine in gentle gear to keep her steady. Going uphill, water entering the chamber pushes the boat forward and across, so a touch of forward gear with the rudder turned towards the wall helps hold her straight. Going downhill, keep an eye behind you for the cill and the bottom gates, and be ready to ease the boat back as the water drops. Lift the fenders on the gate side before you enter — a fender trapped between hull and gate can do real damage.

Ropes and paddles: take direction, take turns

• Take a rope when it's offered rather than standing back, but take a turn around a bollard and hold it — never knot it. A boat being lifted or dropped by a rising lock cannot be held by a line that's been made fast.
• Never wrap a rope around your hand or wrist. Coil it loosely and keep fingers clear of the bollard.
• Lift ground paddles first, and lift them slowly. The water they let in arrives below the surface, which is far gentler on the boats.
• Leave gate paddles until the water has settled, and even then a couple of turns is plenty. A gate paddle opened wide sends a jet of water straight at the bow.
• On a double gate, wind paddles up evenly on both sides. Opening one fully while the other stays shut pins the boat to one wall.
• Wind paddles down rather than letting them drop. Dropped paddles bend, and everybody waiting behind you pays for it.
• If you're told to hold, hold. Second-guessing the person at the helm is how ropes end up in the water.

When three or more boats share a lock

Busy stretches of canal can see four or five boats in a wide lock at once, and there's a knack to it. Boats generally raft up two abreast, with the deepest-draughted boat closest to the bottom gates going uphill, and the shallowest nearest the top gates going down. Ask the other helms what they draw if you're unsure.

Once several boats are in, fill the lock more gently still — one paddle at a time, a few turns at that. Expect some nudging and allow for it. Fenders between boats are sensible; fenders against the lock wall are not. If you're the last one in, you may need to shuffle forward or back as the boats settle, so keep a line ashore and stay attentive until the gates are open and everyone is moving.

Patience at the gates, and a good word goes a long way

Don't rush the gates. Wait until the water has stopped moving before you push them open, or the surge will shove a boat into the gate. Close them gently behind you, and check the paddles are down before you walk away.

You will meet single-handers doing three jobs at once, hire boats on their first morning, and crews who have been locking for forty years and could do it in their sleep. Offer help before you offer criticism, and accept it gracefully when it's offered to you. A quiet "shall I take your bow line?" solves more problems than any amount of advice shouted from the tiller.

Thank the people who helped you through, and help the next boat along. That's the whole of canal etiquette, really — and it's why locking, for all its clatter and cold hands, is often the best part of the day.