5 Warning Signs That Your Boat is About to Sink in a Lock

Marsworth Lock 39

Lock 39, Grand Union, Marsworth

This week a canal boat suddenly and sadly sank in Cassiobury Park in Watford (reported The Watford Observer). The Grand Union Canal at Iron Bridge Lock was expected to be closed for a few days while the boat was recovered. A Canal & River Trust spokesman said the accident was probably due to “boater error”.

Frighteningly, with a lapse of concentration this can happen to even the most experienced boater.

Here are 5 warning signs that your boat is about to sink in a lock.

1. You’re in a Hurry

Don’t run beside a lock or jump on and off the boat unnecessarily. Taking your time means you can be more aware of everything going on around you, including the positions of other crew members, the paddles and the boat.

2. You’re Distracted

Whether you’re dealing with children, teenagers or your dog, or you’ve popped inside to put the kettle on, make sure that at least someone on the crew is 100 percent focussed on operating the lock! A moment looking in the wrong direction can be disastrous as a narrowboat can sink very quickly in a lock.

3. You’ve Tied the Midrope to a Bollard And You’re Going Downhill

When going up a lock, a boat should be tied up so that it doesn’t move around too much when the water rushes in. When going down a lock, never tie up the boat or it will be left hanging by a rope whilst the water level rapidly falls.

4. Water From Leaking Gates or Open Paddles is Pouring into the Front Deck

Don’t think that your little front deck drainage holes can cope with a rapid influx of water! If your bow is too close to the front lock gate water could be filling your well deck while you are chatting and drinking tea at the stern.

5. You’re Not Aware of the Cill Marker

Keep your boat away from the top and bottom gates to prevent it getting caught on the gate or the lock cill. When I upgraded from a 57ft narrowboat to a 72ft I was travelling solo and operating a lock. I was so conscious of making sure that the stern didn’t catch on the cill that I wasn’t paying attention to my button fender on the bow. It got caught on the front lock gate as I emptied the lock and very quickly the stern continued to go down while the bow remained pointed upwards, tipping the boat to an alarming angle! By quickly dropping the paddles I was able to refill the lock and prevent a disaster.

You may think that these are silly mistakes to make, but an overtired or distracted skipper can be prone to disastrous errors. Have you had any near-misses or almost disastrous moments in a lock? Have you ever had to urgently drop the paddles to prevent a disaster? Go on – admit it! Are there any top lock tips we’ve not mentioned? Let us know on Facebook or leave us a comment below.

Want to go from boat enthusiast to pro skipper? Try volunteering with your local community boating project or improve your skills with NCBA accredited training.

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  1. Stephen 13th October 2014 at 12:59 - Reply

    Terrible headline. Good advice.

  2. Rob 13th October 2014 at 14:47 - Reply

    Happened to us only a couple of days ago” 2 boats in the lock, one got caught on a protrusion on the lock wall – frightening how quickly the boat dropped at an angle, water was a couple of inches from the rear deck as we slammed the bottom paddles shut and would the top paddles like maniacs!

    • Narrowboat Wife 13th October 2014 at 15:03 - Reply

      Yes it’s amazing how fast it all happens. I’ve shared a lock with someone whose boat got stuck on the cill and we yelled “Drop the paddles!” and averted disaster just in time! It was at Denham Deep…

  3. Tony Bowyer 22nd October 2014 at 09:39 - Reply

    I don’t think anyone should be ‘popping inside for a cuppa’ in a lock – you need a fully attentive person at the helm and crew on the lockside should ALWAYS be looking at the helmsperson and checking they are are content with the operation of the lock gates and paddles throughout the procedure, however tempting it is to chat with gongoozlers.

  4. Narrowboat Wife 22nd October 2014 at 10:00 - Reply

    I agree that all crew on the lockside should be paying attention to operating the lock, but I don’t see any harm in someone making a cup of tea if they’re not needed by the rest of the crew 🙂

  5. Linda 9th November 2014 at 20:28 - Reply

    Never tie your boat up when going up a lock, it can turn over if you run out of slack in the rope. Open the paddles SLOWLY (like, in slow motion) to stop the boat surging about. Pass the centre rope round a lockside bollard and back to the steerer who can lengthen or shorten the rope as necessary to hold the boat steady

  6. Narrowboat Wife 11th November 2014 at 12:32 - Reply

    Great advice Linda. I do tie up if I’m boating alone and need to operate the paddles and gates, but I suppose that’s not really relevant when I’m writing about community boating, where there is usually a decent crew on board to help with everything. My mistake! Looping a rope around a bollard and passing it to the steerer is definitely the best way to do it.

  7. contentedsouls 11th November 2014 at 13:41 - Reply

    Front rope got caught in a weld in the lock ladder as we went down. If the skipper on the boat in front hadn’t thrown me a knife we would have been an ‘ex’ narra. When it goes wrong it does it VERY quickly. In France and pulled the emergency rod but went down 4 more feet before it stopped. Automatic here so no control – can’t stop anything. Terrifying.

    • Narrowboat Wife 11th November 2014 at 16:40 - Reply

      That does sound terrifying! Glad you managed to save the situation in time.

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