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Garden hose flow rate

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catstail | 13:09 Thu 26th May 2011 | Home & Garden
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I need to replace my 1/2 inch 50m watering hose on my allotment. The stand pipe has a 1/2 inch tap. The water has to flow a foot uphill. Would I get an increased flow rate if I used a hose wider than the standard 1/2 inch? (I am allowed 30 min water per day. Some people have enough pressure to use sprinklers ++. At present the flow from my aged hose is feeble.)
Many thanks.
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Shows how much I know. I'd have figured that if the hole diameter was comparable to the copper pipe that fed the tap, chances are it is mains pressure that makes the difference rather than the hosepipe diameter.

But why not get a short length and see ?
Get a bucket; fill it direct from the tap, timing how long it takes to fill. Fill the same bucket at the end of your 50m hose again timing the event. This will make the decision for you.
Question Author
Thanks for the suggestiions. I'm wondering if the 1/2inch tap would be the limiting factor and that investing in 3/4 or 1 inch width hose wouldn't make any difference. I do know that the 50m length affects the pressure I will get out, but I can't do anything about that.
Perhaps I need to learn about the physics of flow through a pipe.
It will not make more than a halpeworth of difference. Get a standard hose.
You have too much time on your hands : )
Considering that mains water pressure will enter a house at ground level and pump water up to the storage tank in the loft I can't see how a one foot increase in the ground level can make any difference.
I agree with Albags.
I agree with Albags that one foot of height makes no difference.
But I do not agree in relation in the pipe diameter. The physics of it would indicate that the flow of water from the hose end depend upon:
the dynamic pressure at the standpipe end (when water is flowing)
the length of the hose
the diameter of the hosepipe
The trouble is that it is going to be difficult to calculate the impact of any difference and other factors come into play. For instance, the dynamic pressure at the standpipe depends on the length of the feedpipe and its diameter (the pipe in the ground - and you can't control that).
As an aside, if you want to maximise the amount of water being extracted in your precious 30 minutes (irrespective of what diameter hose you finally choose), try to water at a time when FEW OTHERS are also watering - the dynamic water pressure at your standpipe will be at its highest.
Focus have 20% off irrigation products, as part of their closing down sale, though I know this doesn't answer your question.
The pressure available to you is very important, as others have pointed out, and you have no control over that but buildersmate's advice is precisely correct. Since the length you require is in effect dictated to you, the only factor you have control over is the diameter of the hose. Yes, a larger diameter would reduce the resistance to flow through the hose and the more rigid and smooth on the inside it is then the less resistance you will suffer. Fifty metres of hose is quite a substatial length and in actual fact, if you were to conduct a test, there would come a point whereby continually lengthening the run of hose would result in a mere trickle even on the horizontal with the tap fully open - but currently a 30cm rise probably does not have the biggest effect although (in your test) you could cut the flow completely for a good while simply by raising the end of the hose 30cm. My advice would be to get a larger diameter hose and try to make sure it is unlikely to kink/collapse (thicker walled is better) and is the smoothest one on the inside on offer. Then look after your hose, coiling it carefully for storage and fastidiously avoid kinking or squashing in any way.
One other suggestion for you, Catstail?
Keep your eyes open for an allotment site becoming available in the future which is downhill from the stand pipe and get your name down on the list first.
Question Author
Many thanks everyone.
Will look for a smooth inner-walled garden hose. If I can find an affordable wider-bored hose I will go for that. To be honest I suspect anything will be better than my aged and cheap garden hose. Hopefully either way I can spend less time watering in these very dry spells. Perhaps it might even rain.
If you have one of those modern flow stop connectors on it, that might be slowing the flow rate.

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