Why don’t canals flood?

Where the heck has January gone? It’s supposed to last about 3,000 days after the excitement of Christmas and New Year, this January has just zoomed by.  Whoosh.

It came to my attention the other day that the last thing I rattled on about was phone batteries and that was away back in December, the 18th to be precise.  Nothing’s changed on the phone battery front.  On Monday morning it was 100% when I left the house and five minutes later when I took it out to use an m-ticket the bloody phone was switched off.  When I tried to switch it on it indicated it needed charged.

Thankfully I had my booster with me and managed to get it on but it died again and I had to let the bus go.  Managed get the next one.  Just.  Will need to deal with the battery shortly…by next year at least.

The other night I was having a fairly decent nights sleep.  I’d gone to bed at nine and fallen asleep not long after.  I woke about twelve urgently needing to use the bathroom.  I decided to have a cup of tea as I didn’t think I would get back to sleep immediately, I really felt too awake.

Tea drunk, I snuggled back under my duvet and rolled my self into it a bit.  On my side, hot water bottle in a bear hug and the radio on.

I don’t listen to music radio at that time of night.  I listen to talk radio.  I keep it on in the background.  If I can’t sleep then it’s something to listen to, maybe to help me drop off.  Or, it’s just soothes me back to sleep.

On this night it lulled me off to sleep.

Fast forward until about 4.20am.  My eyes flew open to find Dog standing on me and looking down at me.  He’s no lightweight.  A cross lab/collie and he’s black so in the dark it’s even more frightening.  I came to and looked at him, he was just staring at me and for one strange moment I thought he was sleep walking. I wondered how to awaken him.

He then tried to lie down before huffily getting on my bad when I made it clear I wasn’t going to move.  He went off to find somewhere else to sleep.  Good for him.

Of course, I couldn’t fall asleep immediately.  I would have loved to.  Only, I’d been startled awake by Creepy Dug so falling asleep again quickly seemed to be out of the question.  I was lying there, curled up on my side, cosy in my bed with the radio on in the background unable to fall back asleep.   There in the dark, hugging my hot water bottle and out of no where came the question…

Why don’t canals flood?

It literally dropped down on me like an unexpected bird splat.  Now that I’d thought about it I couldn’t not think about it.  I started to think about why this had come into my head.

Here in Edinburgh we have the Water of Leith that spills out into the Firth of Forth.  The river cuts through the city so sometimes it gets a bit over excited and when it rains a lot or there is a surge then the banks can’t hold it and whoooosh, it comes over its banks.

Yet the canal never does.  In the heaviest of rains the Union Canal doesn’t flood.  One of the reasons this came into my mind was that the canal runs across the Longstone/Slateford area of the city as a viaduct.  A man made structure helps the canal along its route by being above the streets and houses.  I tried to recall if there was any time during any of the times the Water of Leith had burst its banks if the canal had done the same meaning that water would pour over the viaduct in a waterfall type effect onto the flats below, onto the road aswell.  I’d never heard of it which led me to think that canals don’t flood.  I had never heard of a canal flooding so…why?

Well, they can do.  Though it is very, very rare and the reason is that because canals are man made there are lots of ways of regulating the water level and this is what they who run the canals do.  There is an alarm system.

With the monitoring we have in place across the canals and rivers we are able to see what is happening in specific areas. If water levels rise, the monitoring system sends an alert and indicates to us a possible problem.

We remove excess water in a number of ways:

  • we try to ensure weirs which send water out of the canal are not blocked
  • we try to turn down the amount of water entering the canal in the flooded area
  • we try to get the water out of the canal as quickly as possible, using large valves known as sluices
  • if a canal has high water levels, it may be possible to move water through locks, down to unaffected locations

That’s from the Canal and River Trust.

How amazing.  Genuinely.

Canals came in to being because of necessity.  The mother of all invention.  People needed to transport things from their origins, perhaps coal, to where it was needed.  Not got a railway? Build a canal.  Thank you the Victorians.  The canals not always as popular as the railways but every bit as important.

Today canals tend to be more for barges, lovely walks along the tow paths and an entirely serene way of living.  I could get on board with that.

3 thoughts on “Why don’t canals flood?

  1. Quora brought me here (and procrastination…). Enjoyed the read, disregarding the weird language (quote: “Now that’s I’d thought about it I couldn’t not think about it.”).
    And you’re in good company thinking about why canals don’t flood (Ecc 1:7).
    Perhaps you in turn can think about how sunbeams can conserve their energy and we feel their warmth, having travelled the long journey in cold empty space, haha?
    Anyway, looking foreward to the next post. Stay frosty.

    1. I think the weird language might be down to me not editing the blog properly. Still haven’t done it. Thank you for reading and the next post is never far away. 🙂

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