How to Operate a Canal Lock:
1. Approach the lock and discuss if there is anyone in the lock, is there anyone coming toward the lock that might have priority, and if there is a line waiting in front of us or are they just tied up to get some water?
2. Approach lock standing area – recognizable due to the iron posts or rings to help hold the boat. Allow one crew member to disembark with the holding line and to help stabilize the boat (see this post). Once the boat is stable, the person on the shore hands the holding rope back to the other crew member and runs toward the lock, lock key in hand. The lock key is a big l-shaped bar of metal with two square openings at one end. This crew member has just become the lock opener.
3. The lock opener surveys the situation. Which doors are open? Which panels are open? Is there a boat in the lock or approaching the lock from the other direction. Are there other folks around already working the lot?
5. The doors at the downstream end of the lock need to be opened but that doesn’t work if the lock is full of water. The doors open into the lock and against the water. So, the panels must be raised with the lock key that will release the water. The square hole fits over a shaft that runs some gears that open and close the panels. There are two panels, one for each of the door doors on the downstream lock side. Open up one panel, then walk across the doors along a freakingly narrow beam to the other side and the other panel.
6. Once the water level inside the lock is even with the water on the down stream side, start pushing the doors open. This is fun because clearly you are using physics and levers to move some very heavy chunks of wood. Also, you’re pushing this really huge lever with your butt. And your legs.
7. While your boat enters the lock, you start dropping the panel on the side you are standing on because you are going to want the water. Once your boat is in the lock, close the door on the side you are standing. Then, if you have been living the boat life for years and your legs are long and you are fearless and/or stupid, you cross back over with a big step to the other half of the gate where you close the panel and the door. If you are more self-preservation aware, then you run up to the upstream side of the lock, walk across the freakingly narrow beam on the front gate to the other side of the lock and then run back to close the second half of the door.
8. Then you go back to the upstream side of the lock and start opening the upstream panels to let the water come into the lock. You open it slowly at first because that’s a lot of water to start pouring into the lock.
9. Meanwhile, the person driving the boat moves the boat backwards and forwards within the lock so it doesn’t get pressed up against a door or filled in front with the incoming waterfall. Profanity may or may not be involved, depending on the driver.
10. Once the water level has equalized with the upstream side, the door (usually upstream is a single gate) needs to be pushed open and then re-closed after the boat passes out of the lock. The panels are dropped so that the lock is ready for another boat from either direction.
11. The lock opener then runs up to where the boat has bashed its way back to the shore – usually a bow tip touch, and then jumps back on the boat.
If you want to see the pro video – Locks are covered starting at 8:54 in this video (plus a lot of other good stuff about how to narrowboat).