Canals and narrowboats questions

Boo2

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Just curious :

How many horsepower does it take to actually move a narrowboat ? Ie, not how many hp their engines are rated at, but how many are actually used ?

What is the current water quality like in our canals generally these days ?

Are there any fish in our canals ? If so which species preponderate ?

How many canal boats empty their heads / showers / sinks into the canal ? a) in theory b) in practice ?

Thanks,

Boo2
 

rotrax

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My 40 foot steel narrowboat had a really frugal Yanmar 12 HP single cylinder diesel. The only time we found it short of power was on the Tidal Thames and the upper river and the Cherwell in flood conditions of high flow rates.

No idea what the water quality is now, but four years ago on the K&A it was fine.

Plenty of fish in our canals, species depend on area. Roach and Perch very common, Gudgeon everywhere, large Carp in the summit level of the GU, Tring to Cowroast.

If anyone IS emptying their toilets in the cut they are breaking the bylaws.

They will not admit, so we shall never know.

Standard practice for showers/sinks to drain directly into the cut. Also bilge water. Certainly on all the narrowboats I have owned or hired.

I hope this helps.
 

TrueBlue

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This is a form for the Thames and most 'residents' on this forum have other types of boats and are unfamiliar with the canal system.
If you want a different perspective have a look here -
Canal World
However, Rotrax above pretty well sums it up. His comments also apply to the Thames.
The Thames is wider and deeper than the canals, thus any pollution is diluted quicker than on the canal system. Both have reasonable facilities to dispose of rubbish and toilet waste. However, there are ever increasing numbers of boats which don't move, thus I wonder how they dispose of their wast matter...
 

ryanroberts

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Newer narrowboats are probably over engined for propulsion, particularly in a canal where if you run a 40HP engine at more than 1600 RPM you are going to chuck the water out of the canal. The only time I have ever needed full chat was getting through Osney bridge on yellow boards. Mostly the additional engine power is for running large alternators. Mostly the canals are pretty pollution free (though unfortunately there can be quite a lot of rubbish near towns), the river Lea is probably the nastiest stretch I have been on due to sewage overflow.

Almost all narrowboats will empty grey water into the canal - washing machines in particular can produce quite a slick where there is little flow, but very rarely anything else. Some stretches of river (at least the Trent that I know of) black water discharge is allowed but frowned on.
 

Gibeltarik

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Our 43ft narrowboat has 21 bhp Beta and has successfully traveled upstream from Windsor to Oxford on Red Boards in the past.
 

TrueBlue

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Norra lot of good in reverse....

Regardless on t'thames it was a team of horses and a proper size to boot. Canal equines were not much more than pony size.

I asked BW if we could use our horse on the Shroppie - and they replied 'the canals weren't suitable for horses'...
 

Boater Sam

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In normal canal cruising mode I would doubt that any more than 5 to 7 HP is going usefully to the blade. The requirement for more engine HP is so that it is running at not much over tick over. A 50 HP engine probably only develops that at around 3500 rpm.
And alternators will absorb another 1 to 3 HP depending on size and battery charge state.
A bit in excess is handy when it comes to stopping, the hull and blade are less efficient in reverse.
 

rotrax

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In normal canal cruising mode I would doubt that any more than 5 to 7 HP is going usefully to the blade. The requirement for more engine HP is so that it is running at not much over tick over. A 50 HP engine probably only develops that at around 3500 rpm.
And alternators will absorb another 1 to 3 HP depending on size and battery charge state.
A bit in excess is handy when it comes to stopping, the hull and blade are less efficient in reverse.

I agree fully with your last sentence.

Our old 12HP Yanmar had a dynostart, but with the engine running all day when moving it was fine. Simple boat, gas fridge, gas water heater, minimal lighting, only the water pump for the domestic water and lighting drew current from the two old lorry batteries.

Stopping WAS interesting on many occasions! Bit of a current or a tailwind and even at full rattle in astern it was touch and go. When locking on the canals I got very good at catching the stern line and getting it fixed around something to check forward progress! Trickier going up as the angles were all wrong.

Best thing was it would run for ten hours and only use a few litres of fuel, especially after I pulled it in bits, overhauled it and got my man Takis the Bubble to do the injector.

It had an epicyclic gearbox, expanding internal clutch for astern and a contracting band, steel on steel, for ahead. The band was shagged out, barely holding.

I got my mate with a big lathe to true it up a bit and the local brake reliner bonded a section of brake lining material inside where it contracted onto the drum.

I dont know why that was not done on production as it was a massive improvement, far quieter and smoother.

Thank you for reminding me of those happy times in the early to late 70's with our basic canal boat. The waterways were far quieter then too.
 
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