Water storage

slowworm

Full Member
May 8, 2008
2,179
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Devon
I know from our water butts it can vary greatly depending on the wind direction. On a good day one 210L butt can fill in less than half an hour.

We had about 5cm rain here in Sussex, assuming a 50 square metre roof then your 5 ibcs could be over half full.

Edit to say you probably had less rain but a bigger roof, so about the same guess.
 
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British Red

M.A.B (Mad About Bushcraft)
Dec 30, 2005
26,891
2,143
Mercia
Certainly you and Broch are on the right track. I overfilled the two isolated tanks so 2,500 litres is probably pretty good as a guess.

To many people that seems a vast amount.

However it hasn't rained for about 6 weeks here...42 days.


If I need to water the vegetable garden, I put a 3.5 bar pump onto the tanks which gives us mains pressure

So my 10,000 litres would allow just 15 minutes a day of watering assuming I want to use it only on the garden.

The average person in the UK uses 142 litres per day domestically. So 10,000 litres would last two people , without garden use, for a month. Assuming 15 minutes of watering, under 3 weeks.

For me, in drought times, two factors come into play.

1) Enough roof space to harvest a good quantity of the rain that dies fall

2) Enough storage capacity to capture sufficient water until the next rainfall.

The numbers involved are eye opening to me!
.
 
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TeeDee

Full Member
Nov 6, 2008
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A little over that. Which seems huge, but it's two hours of watering or a weeks domestic water for a couple!

So from what you've said, catchment vs storage - as one is unlikely to increase roof space for catchment - that just leaves additional storage.

So do you have plans to increase?
 
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British Red

M.A.B (Mad About Bushcraft)
Dec 30, 2005
26,891
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So from what you've said, catchment vs storage - as one is unlikely to increase roof space for catchment - that just leaves additional storage.

So do you have plans to increase?
Thankfully our above ground 10,000litres is in addition to a brick built underground system and a functional well. The other 5 tanks hang off other outbuilding roofs. Its possible to gather 6,000 litres in 24 hours of rain. The cottage gutters replenish the underground cistern.

The well water is slightly brackish (we are in the fens after all) so, in a total water crisis, we would favour that for the garden, reserving the cistern and IBC tanks for humans and livestock
 
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British Red

M.A.B (Mad About Bushcraft)
Dec 30, 2005
26,891
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Oops you're right! - but if the roof area is 10m x 10m and you get 50mm (2") water that would be 5 cubic meters = 5,000L
Good maths! I think we got about 2,500L yesterday which is consistent (the harvesting is also far from 100% efficient).

For me, the point is very much that a 200L water butt equates to 12 minutes of a tap running or less than half a days domestic needs for a family of 4 :oops:
 
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TeeDee

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Nov 6, 2008
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I am fortunate I have a River to the front of me and a Stream to the side. Counting my blessings.
 

British Red

M.A.B (Mad About Bushcraft)
Dec 30, 2005
26,891
2,143
Mercia
Already in situa. Have an IBC as an Cold Immersion tank and half a dozen water butts. Doesn't seem enough but water takes up a lot of space.
It does indeed, sounds like you are sorted. A pump that can move water around is pretty vital imo
 
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TeeDee

Full Member
Nov 6, 2008
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Exeter
Actually that does remind me - I purchased a 1500l old Fuel Oil tank someone had been using on an allotment for water storage.

I had it delivered but have discovered it has some weeping points where it loses water - slowly - but it does lose it.

Any clever ways or ideas on the best way to find the various leaky points? Dye maybe?
 

British Red

M.A.B (Mad About Bushcraft)
Dec 30, 2005
26,891
2,143
Mercia
Actually that does remind me - I purchased a 1500l old Fuel Oil tank someone had been using on an allotment for water storage.

I had it delivered but have discovered it has some weeping points where it loses water - slowly - but it does lose it.

Any clever ways or ideas on the best way to find the various leaky points? Dye maybe?
This stuff is awesome. Tiny amount in a drain and you can trace the outfall hundreds of meters away

 
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Mesquite

It is what it is.
Mar 5, 2008
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~Hemel Hempstead~
This stuff is awesome. Tiny amount in a drain and you can trace the outfall hundreds of meters away

Oh yes, that stuff is really good and you don't need a lot either.

I once turned a river 20ft wide bright flourescent green for nearly 1/2 mile with it when we were tracing a drain during a pollution event and I accidently dropped a full tub in the drain... We certainly proved the drain connection to the river but boy did it generate a lot of concerned folks phoning in to report a bright green river :lmao:
 

Broch

Life Member
Jan 18, 2009
8,490
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Mid Wales
www.mont-hmg.co.uk
When I was looking into water supply problem mitigation a short while ago I carried out a rough usage analysis. The national average is about 150L/person/day apparently. For a two person household however that varies from around 50,000 to 140,000 L/year (136 to 383L/day) - so there are huge variations.

My own personal analysis suggest that, without restriction, we are using around 225L/day and, if we had to cut back, we would use as low as 100L/day. All this is ignoring any veg patch watering etc.

This all meant that if my only reserve was a 1000L IBC it would only last 10 days on our reduced consumption :(

I am mitigating against:
a) loss of electrical power - solved with a generator if there is diesel, otherwise 10 days is fine for a normal world
b) failure of the borehole pump - 10 days may be enough to get a replacement - should I buy a spare?
c) our water supply (100m down) runs dry - 10 days would allow us to pack up and leave :)
 

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