Fill my water tank from lake?

Forums › Home Workshop DIY › Fill my water tank from lake?

1 | 2 | 3 | 4 | 5

2641 posts

Uber Geek
+1 received by user: 1137

#3178786 7-Jan-2024 15:41

boosacnoodle:

tweake: 25000 liter tank is really bare minimum and unless your born and bred on conserving water you will run out. the standard today is typically 2x 25000 liter tanks and often is 3x. the yearly rain fall is typically more than enough in most places in nz. storage is typically the big issue.

Really? I grew up in a household of 7 and seldom ever ran out with "just" two 10,000 litre tanks.

it depends a bit on the area etc. some places get enough consistent rainfall that they use small tanks. but, like the one that hit the news a few years back, if you get a longer than normal dry spell your stuffed.

we where 4 on 25,000 but we grew up with that. we have loads of townies moving in here who run out very very quickly. even 50,000 is not enough. (bit of local entertainment watching townies run out of water).

Hwale

71 posts

Master Geek
+1 received by user: 19

#3178790 7-Jan-2024 15:56

Even if we could collect 90,000 a year, a low average household usage is over 100,000 litres a year. And if we could collect more than we use, we wouldn't need the storage because our catchment would be big enough to utilise the monthly rainfall.

Based on our catchment and low average usage, if our annual rainfall doubled it would still take a year to fill two 25,000 litre tanks.

tweake

2641 posts

Uber Geek
+1 received by user: 1137

#3178793 7-Jan-2024 16:04

Hwale: Even if we could collect 90,000 a year, a low average household usage is over 100,000 litres a year. And if we could collect more than we use, we wouldn't need the storage because our catchment would be big enough to utilise the monthly rainfall.

Based on our catchment and low average usage, if our annual rainfall doubled it would still take a year to fill two 25,000 litre tanks.

what size is your catchment?

jaymz

1136 posts

Uber Geek
+1 received by user: 76

#3178797 7-Jan-2024 16:27

We recently had the task of filling up a pool for the kids over summer.

We too are on tank water, but thankfully predicted the weather well and gambled that there would be enough rainfall to replenish the 19,000L that was needed.

I utilized a submersible pump from Bunnings (https://www.bunnings.co.nz/ozito-350w-submersible-water-pump-psdw-350_p4816179?store=9434&gad_source=1) to pull the water from the tank into the pool.

I had the luxury of mains power nearby, something it sounds like you won't have.

Whilst it was running, I used a 10L bucket and worked out the flow rate to give me an idea on how long it would take.

With the location you will be pumping from, is it secure enough to leave on IBC or 1000L tank there filling whilst you take the full tank back to empty into the water tank?

I know the water delivery trucks have a petrol "trash" pump on the truck to dump the water into people's tanks when delivering, this might be something to invest in or beg/borrow one to use.

tweake

2641 posts

Uber Geek
+1 received by user: 1137

#3178805 7-Jan-2024 17:22

for filling ibc's there is plenty of cheap trash pumps around. 50mm, $400-500 range, gx120 clones. some suction hose and screen end from lake to pump. then a roll of lay flat hose from pump to ibc/tank. 2.5 ton trailler with two ibc would work well. if you have a ute, another ibc on that. those pumps will fill them up pretty quick, i suggest having some means to tie the hose in place in the tank. ibc fittings is usually a pita to get the right ones. bit of suction hose for ibc to pump for pumping into the tank. hook for the tank if you can. camlocks for the hose connections.

LostOhSoLost

13 posts

Geek
+1 received by user: 20

#3178806 7-Jan-2024 17:31

A collection of thoughts:

Any of your neighbours got a digital weather station that you could get some local rain fall data from so you can develop some hard numbers?

Pumping out of the lake via a pipe to the house isn't going to be cheap, atleast $900 just for water pipe and then you have to roll it out and roll it up which may not be as easy as it seems. If there are convent culverts under the road to pass the pipe though may allow it to be slightly less temporary.

Have you considered gray water recycling (is it practical in your house), given 20% of water usage is for toilets it could make robust inroads to your water usage.

Build a sun shade over the existing water tank and get an extra 10 square meters of catchment (& a more consistent water temperature in the house).

Lenovo

Shop now for Lenovo laptops and other devices (affiliate link).

tweake

2641 posts

Uber Geek
+1 received by user: 1137

#3178808 7-Jan-2024 17:46

LostOhSoLost:

Pumping out of the lake via a pipe to the house isn't going to be cheap, atleast $900 just for water pipe and then you have to roll it out and roll it up which may not be as easy as it seems.

for temp roll flat hose, nice and easy to roll up, its about $200 for 50m. the suction pipe from lake to pump is the expensive part. as long as the length required isn't to long, whole setup of pump, ibc, hoses etc should be $1000ish.

rhy7s

673 posts

Ultimate Geek
+1 received by user: 147

#3178833 7-Jan-2024 21:20

Hwale:

If I thought I'd be doing it 3.8 billion times I'd reconsider.

Distance from lake to house is about 250m across a couple of small very quiet roads. It's possible but it would be a bit of a logistical headache.

Extra tanks aren't really an option, I think it doesn't rain here enough anyway and our roof catchment isn't that great so a readily available supply would be better.

We get our bulk water via a 750m alkathene line to the dam. A siphon over the wall and gravity feed to settling tanks, then pump it up to our header, 250m is not much at all if access is feasible.

MikeAqua

8024 posts

Uber Geek
+1 received by user: 3818

#3178930 8-Jan-2024 11:30

If this was me, I'd invest in cheap genny and a submersible pump, to fill IBCs. Ideally one on a ute and two on a trailer. Or buy my own 3,000L tanker. 900mm of rain in a year isn't much. And rain being rain it doesn't arrive in convenient regular amounts. Often heavy events top up your tank and then overflow. It's possible to lose a chunk of annual rainfall this way.

Regarding bores and septic tanks, the local Environment Plan will usually stipulate a minimum separation between a bore and the presumed soakage field of adjacent septic tanks.

A bore (assuming there is a suitable aquifer present) is a much better long-term solution than rain-water or lake-water. It's more dependable than the rain, and less prone to pollution and toxins than a lake. Of course the feasibility of a bore depends on the local geology.

Tanks: You can never have too many (unless you're on slip prone land!). 50,000 is considered the minimum amount required for fire-fighting (according to my local council). On our rural property we have a bore. We will have 3 x 25,000L tanks. One tank is for everyday domestic, garden and washing vehicles but also able to supply roof-sprinklers. The other two will be setup with a fire-truck connection. We also have ponds.

OP If you're rural in a dry area, I would suggest having a think about fire-fighting.

Mike

Sidestep

1019 posts

Uber Geek
+1 received by user: 567

Lifetime subscriber

#3178983 8-Jan-2024 13:41

For a long time I ran a remote accommodation business w/ 310m2 of roof feeding 60,000l of storage.

800m away was our house 250m2 feeding 50,000l of storage.

As you can guess, the 15-20 guest commercial accom ran out of water much faster than the house with our water aware family.

Right when we ran out of water (Aupouri Peninsula has basically dry summer and wet winter seasons), so would everyone else.
The wait for a 10,000l water tanker to do a 120km round trip could be weeks.

I purchased an old MF135 tractor for $800, a very decrepit H/D farm trailer for a few hundred and 5, 1,000l IBC tanks.
With a PTO mounted pump I could easily shift 10,000l in a morning, probably empty a 25k tankful in a day - though I never had to.

If you're going to move water regularly I'd recommend setting up a dedicated carrier & pumping system.

After 8 years I finally bit the bullet, called Kiwi Drilling & put a bore down at the commercial building.

Well below any possible septic soakage at 60m, we do regular water tests and have never had bacterial contamination from the bore (unlike water tank tests)
All the water's treated though ozonation + sand filtering/backwashing (via an old swimming pool filter) then UV to sterile header tank, then filter anyway.

Hwale

71 posts

Master Geek
+1 received by user: 19

#3179210 9-Jan-2024 01:35

Just to put to rest the '50,000 litre tank is bare minimum' theory, this may be true in wet or seasonal rainfall regions but not here. Our wettest month receives 75mm rainfall. To catch 50,000 litres from this over a one month period drawing a low average household usage of 300 litres a day, we would either need a roof catchment of around 800 square meters - 4 or 5 times the size of the average NZ house - or we would need to receive over 700mm of rainfall in one month, nearly ten times the wettest monthly average.

Contrast this with somewhere like Rotorua, where the wettest month has over 136mm rainfall and there'd be a net daily gain of around 150 liters with only a modest 100m^2 catchment.

New World

Shop on-line at New World now for your groceries (affiliate link).

Ge0rge

2114 posts

Uber Geek
+1 received by user: 2060

Trusted

Lifetime subscriber

#3179216 9-Jan-2024 06:53

I don't suppose you feel like joining the local volunteer fire brigade, or know someone who is?

MikeAqua

8024 posts

Uber Geek
+1 received by user: 3818

#3179383 9-Jan-2024 14:42

Hwale:

Just to put to rest the '50,000 litre tank is bare minimum' theory, this may be true in wet or seasonal rainfall regions but not here.

I'm one of the people who made the suggestion. It was based on fire-readiness advice I received from my local council and backed up by colleagues who are Volunteer firefighters.

Fire-fighting (I am told) is about putting the wet-stuff on the hot-stuff, ASAP.

Without having a reservoir of fire-fighting water (however you get it) that will be harder/slower than it could be.

We're building somewhere hot, dry and rural. We will have 2 x 25,000L tanks just for fire-fighting, with the ability to rapidly fill these from ponds.

Day to day, our drinking water will flow through the fire-fighting tanks into the domestic tank, so the water turns over all the time.

Mike

Hwale

71 posts

Master Geek
+1 received by user: 19

#3180130 10-Jan-2024 17:42

I've discovered a fairly substantial culvert under the 'busy' road. This means I can pump water directly from the lake to my tank with 250m of layflat hose.

Looks like the best option for the pump is a Honda WX15; it's a 1½ inch with a 40m head. My tank is about 25m above lake level so running 250m of hose up 25m of elevation should be no problem for it even with frictional losses.

There's still the minor issue of a very small quiet road outside my house which typically has maybe 5 vehicles per day, so I could run a hose across it for hours and never see a car. However I need to eliminate the possibility of vehicle damage to the hose. My first thought was to have a coupling (which I'll need anyway) next to the road which I can detach so I can pull the hose off the road when a car comes. If I did this, I'd probably want a valve at the coupling so I'm not just spraying water all over myself when I open the coupling. But then I'd be dead-heading the pump which is probably not a good idea?

I could get a hose ramp but I don't know if you can just go randomly putting those on public roads. Realistically no-one would bother or complain. How resilient are layflat hoses to vehicle damage anyway, should I even worry about such a low traffic area?

Ge0rge

2114 posts

Uber Geek
+1 received by user: 2060

Trusted

Lifetime subscriber

#3180155 10-Jan-2024 18:33

Definitely do something to prevent vehicles driving over the hose. When the hose is fully charged, as opposed to driving over, often car wheels will "push" the hose along and into the road - both stretching the hose, and abrading the surface.

You could put a dividing coupling on the pump side of the road to prevent over-pressure in the pump. Put a short length off the divider, with the main length going to your tank. Car comes, open the short length just a smidge to let a small amount of water flow, close the main delivery and disconnect. I'd look at a QD coupling there as opposed to a threaded one, to make life easier. The small flow from the short length will keep both the temperature and the pressure down in the pump.

Less admin would be a couple of hose ramps and some cones, if indeed the traffic is so light. Plus, you wouldn't have to be there at all times to supervise.

Others may chime in, but I wouldn't have cars driving directly over the hose, charged or not.

1 | 2 | 3 | 4 | 5