Rainwater Harvesting

Guys, do you have any experience with this?

I would want it to save rainwater to use to clean down after lambings etc. Logistically how hard is it? Bury a tank and fit a pump? Do I need access to the tank or could it (hypothetically) go under a concrete floor?

Cannot see it being an issue if underground, as long as the pump is sized to lift the water to the correct height and not just to "move it"

But there again WTF do I know about 'water works'.....he intimated knowingly

Just drinking

Although I have seen it done on TV, I don't think its as simple as it looks (They only show the good bits on TV)

A huge tank was buried in the ground and it was then back filled. (The ground not the tank) I don't see why you couldn't pour concrete over it.

The one on TV did have a man hole cover.

I would say it also needs an accessible  "filter" to stop leaves etc from going into the tank, you don't want that to happen, seen it with my pond.

Pump, depends how high you want the water to go (and pipe work) But i should say a very good sump pump will be fine.

just looked on line, the tanks are NOT cheap,

Yes they do look dear. I'm looking at a possible surgery move and so this is a long term proposition for my lambing shed. Not sure under the concrete floor is going to be the best place. Might consider the lawn instead........

I've seen one built using concrete section of sewage pipe.... 4' diameter stuff. Lid on the bottom, 3 sections of pipe, lid on top with a manhole.

Was all dug out by hand by my customers lad...

Don't know what capacity you're looking at but this sort of thing seems popular at the DIY end of things, the caged LBC containers. Picked at random off eBay but there always seems to be a place "local" to get these wherever you are and prices vary. Even place above ground/on a pier and timber clad to disguise it:

http://www.ebay.co.uk/itm/STEAM-CLEANED-GRADE-A1-IBC-WATER-STORAGE-TANK-RAIN-WATER-1000-LITRE-TANK-C-W-TAP-/290954081151?pt=UK_BOI_FarmingEquipment_RL&hash=item43be36f37f

Again. no affiliation here but the "proper jobs" seem to be set quite deep with a "neck" (and the all important child proof bit). Depends whether you intend driving over it or not. Again, some typical install instructions:

http://www.rainwaterharvesting.co.uk/downloads/carat_tank_instructions_optimax_mains_backup.pdf

EDIT: Just thought...you mentioned the lawn, I have seen I think a 2500ltr one that gets buried in the centre of the lawn. Has a permanently positioned pump/sprinkler attachment on the top and it's remote control. Lawn's looking a brown, pop the sprinkler head on and hit the button!

Id have thought that youd need to ensure that no ground water or yard run off could enter the tank??

Does that add a complication?

If it's on a farm, why bury it?  Just a large tank next to  the barn above ground as high as you can mount it then you might get enough gravity flow.

They do this in Australia for all their water, drinking water as well in some rural parts.

It's an industrial site, but I am in a conservation area, so a bloody great water tower not ideal. It's really to wash down after lambings, and either pump the water to a suitable pressure for a hose to wash down or just enough to power a pressure washer. I was thinking a reasonable sized tank - 5-10,000l, but I'm not sure what I need. Some days in winter we can have a dozen sheep to wash down afterwards, sometimes not use the facility for a month. I don't want to run out in times of need and the extra costs digging a bigger hole or buying a bigger tanks only increase slightly.

The concrete rings - do I just stack them in the ground, pour a concrete base and somehow seal the joins? Fit a top with a manhole cover for access? I have a couple of clients with JCBs - holes are not a problem!

I found this

http://www.rainharvesting.co.uk/pdfs/Concrete%20tanks.pdf

Apache said:

It's an industrial site, but I am in a conservation area, so a bloody great water tower not ideal. It's really to wash down after lambings, and either pump the water to a suitable pressure for a hose to wash down or just enough to power a pressure washer. I was thinking a reasonable sized tank - 5-10,000l, but I'm not sure what I need. Some days in winter we can have a dozen sheep to wash down afterwards, sometimes not use the facility for a month. I don't want to run out in times of need and the extra costs digging a bigger hole or buying a bigger tanks only increase slightly.

The concrete rings - do I just stack them in the ground, pour a concrete base and somehow seal the joins? Fit a top with a manhole cover for access? I have a couple of clients with JCBs - holes are not a problem!

Click to expand...

You need to pay close attention to the "manhole cover" as in to stop kids, livestock falling in so a padlockable grate is the way to go. The main thing with rainwater harvesting is to stick in a filter and to regularly change it. To avoid run off entering then you just have the "inlet" higher. If you go the ring method then as for sealing wouldn't it be better to line with a decent EPDM membrane? All our building's sprinkler tanks are done like this but they do have to be replaced periodically.

I watched a DIY SOS a while back where they put in one of the big plastic tanks.....half a feeling they back filled it with concrete for some reason.....

http://www.stormsaver.com/Domestic-News/Stormsaver-helps-BBC-Ones-DIY-SOS-create-leading-eco-home

Many ways to skin this cat etc.

There's an old smallholding up the road from me where they MADE their storage tank umpteen years ago. The site still has no mains water. Rectangular in shape and I guess cast in-situ from concrete? The bank it's set in has fallen away and has a tree root growing through it but still a fair amount of water in there. I know the new owner so will try and get a photo.

I was working in one of the Crossrail draught relief shafts (goes down 38m below the sub basement level btw) yesterday setting up an electric hoist as they are thickening the existing shaft walls by a metre. I'll see if they have any spare rings........





Remember when they were digging this one and hit a water main..........I'd never seen a JCB underwater before. Wasn't so funny when the sub-station went down though!

main issue is to filter output from tank to ensure water is clean, all stored water can harbour bacteria etc. The storage tank itself can be as complicated or simple as you like, off the shelf stuff tends to command a premium price because it's for 'rainwater harvesting'. Farms abound with storage vessels of one form or another, you could use an old pastic tank as the mould for waterproof concrete structure for example. As for sizing that's not so easy. I have a 20 gallon water butt fed from the roof, which during a drought will last about 3-4weeks of washing the car once a week and a bit of plant watering.

Pressure washers seem to quote usage of 400-600l per hour. Not something I've ever tried to measure, but on a busy day it could be used for up to an hour in 5 minute bursts.

Max 500l per day, that's 3000l over a week if busy. Unlikely to get usage that high, but it's easy even in spring to go a couple of weeks without significant rainfall. Hence a 5-10,000 reservoir is where I was thinking.

Pouring a couple of litres of dairy hypocholorite down each month is fine by me to keep the water fresh!

This keeping water fresh thing puzzles me.

You want water to hose down some sheep.

As I keep saying my SIL down under collects rainwater off every available roof into big tanks for all their water needs including drinking and washing.  It sits for months in the tanks with no treatment and provides them with good clean drinking water in a hot climate where you would think bugs would prevail.

The only significantly different thing there is they have a wet season where it rains a lot, so they collect most of their water for the year in a short period.  I guess that deals with all the bird poo on the roof as it gets heavily diluted.  We tend to get many more wet days but often little rain so here you hight get a higher percentage of "roof dirt" in the water.

I would just collect it and use it without worry.

In NZ our house had gutters that fed all the rainwater into a big tank. It then was fed through a filter. A pump fed the water in to the taps operated via a pressure switch. No water rates, septic tank for sewage. My house here in Wales has a water meter and we are paying through the nose. I have several water butts around the property which collect rainwater from downspouts which we use mainly for gardening. Most houses flush a third of their total water usage down the toilet so I had an idea. there is a large galv water tank in the loft. Connect a submersible pump up operating from a water butt. Feeding the tank via a float valve. When valve operates there could be a pressure switch to turn pump off. Would probably need a low level switch too to restart the filling process. The tank could then feed the toilet cisterns.

 a customer of  mine was doing that manually every day to top up tank from rain water.

Main issue for water filtering is if it is required for drinking ie "potable" but was thinking sheep may have a few cuts from giving birth, so may need a reasonable level of filtering to avoid infecting cuts.

After delivering lambs you end up with blood on the concrete. This is to wash down the floors after the sheep has gone, not to wash the sheep!

I thought you wanted to ba ba ba ba bath the sheep!

Well double knit wool's a ba ba ba bast... To clean so probably need a pressure washer!