Plumbing rain-water into house - options

rampantbunny

I've a large underground in-situ concrete rainwater harvesting tank. Have had early discussions with plumber on how it might be plumbed into house. Plumber suggested going direct from rain-water tank into house. One pump required with the proviso that a pump be sourced to suit the conditions (see bottom of post). My plan was to pump from rain-water tank to buffer tank in garage and from this tank, pump to house.

My plan allows/covers:

1. If pipes from rain-water tank freeze or anything happens on the supply side of things, I will at least have a buffer tank in garage attic to keep me going for a while
2. I might want to purify water in the future and if I do I'd like to do this in the garage to avoid having equipment in the house

But my approach means multiple pumps are needed. Can anyone offer any opinions/alternatives?

Some details:
Tank to garage: 11m
Garage to house: 18m
Bottom of tank to garage attic (is this called the 'head'?): 5m

gctest50

rampantbunny wrote: »

I might want to purify water in the future and if I do I'd like to do this in the garage to avoid having equipment in the house

Do that from the start

rampantbunny wrote: »

If pipes from rain-water tank freeze or anything happens on the supply side of things, I will at least have a buffer tank in garage attic to keep me going for a while

Don't do that - it'll be warm in the summer and the yokes in the water will multiply

rampantbunny

Legionnaires disease?

Garage attic will be insulated.
How is the setup any different from houses with header tank in house attic?
Water in the garage tank will not be stagnant as it will be source of water into the house at all times, so it gets refreshed periodically.

Joe1919

I have the rainwater from the back of my house going into barrel for garden use but I notice that the water is filthy and full of worms, bird feathers, etc. I reckon all the dust from traffic and chimneys, as well as bird droppings etc gets deposited on roof during dry periods and then gets washed down into storage barrel/tank during showers.
For that reason, I would not let roof water into house. However, it may be different for people living out the country and also where there is no chimneys nearby to create dust or attract birds.

rampantbunny

Joe1919 wrote: »

I have the rainwater from the back of my house going into barrel for garden use but I notice that the water is filthy and full of worms, bird feathers, etc. I reckon all the dust from traffic and chimneys, as well as bird droppings etc gets deposited on roof during dry periods and then gets washed down into storage barrel/tank during showers.
For that reason, I would not let roof water into house. However, it may be different for people living out the country and also where there is no chimneys nearby to create dust or attract birds.

Have you any filter on the line? If you don't then I'd expect this. There are products available to minimize the contaminants in the water before it hits the storage tank. I'm in the country but a filter system will still be necessary.

DGOBS

What kind of filter would you be suggesting?
Will the water be UV treated also?
Have you had the system you've put in place tested for dangerous microbiological bacteria by a certified lab?
And if so, and it passed, how often are you going to have this done?

Even your clean water may have things like e-coli and worse lurking.......not healthy stuff to ingest

DGOBS

What kind of filter would you be suggesting?
Will the water be UV treated also?
Have you had the system you've put in place tested for dangerous microbiological bacteria by a certified lab?
And if so, and it passed, how often are you going to have this done?

Even your clean water may have things like e-coli and worse lurking.......not healthy stuff to ingest

marsbar1

I hope you don't mind me butting in on your thread but its a similar topic OP. I'm about to close on an old country house which is on mains water but still has a rainwater collection tank at the back right next to the house. Its a big concrete thing about 10 ft high. I thought about knocking it down but your thread made me question that idea. What with water charges etc is it a good idea to keep it and plumb it in again to use for say showering and toilets etc?

DGOBS

toilets yes, showering...No!

gctest50

DGOBS wrote: »

toilets yes, showering...No!

good practice for yer immune system though

marsbar1

DGOBS wrote: »

toilets yes, showering...No!

I had assumed that when the water is heated in the hot water tank the heat would kill the bacteria but I guess actually it could make some grow then?!
You will have to bear with me I know nothing about Irish country living.

rampantbunny

DGOBS wrote: »

What kind of filter would you be suggesting?
Will the water be UV treated also?
Have you had the system you've put in place tested for dangerous microbiological bacteria by a certified lab?
And if so, and it passed, how often are you going to have this done?

Even your clean water may have things like e-coli and worse lurking.......not healthy stuff to ingest

If I'm suggesting a filter at all, it is to directly minimize this "but I notice that the water is filthy and full of worms, bird feathers.."

I don't have a system installed yet. I started the thread to seek opinions/advice/experience on I might route water from A to B to C. Of course if I plan to filter it by reverse osmosis, UV, pair of tights I'm sure it will have a bearing on how this is done but I'm hoping the filtration system I use won't mean the plumbing is hugely varied.

DGOBS

I had assumed that when the water is heated in the hot water tank the heat would kill the bacteria but I guess actually it could make some grow then?!
You will have to bear with me I know nothing about Irish country living.

You assume correct, bacteria love 'warm' water!

If I'm suggesting a filter at all, it is to directly minimize this "but I notice that the water is filthy and full of worms, bird feathers.."

I don't have a system installed yet. I started the thread to seek opinions/advice/experience on I might route water from A to B to C. Of course if I plan to filter it by reverse osmosis, UV, pair of tights I'm sure it will have a bearing on how this is done but I'm hoping the filtration system I use won't mean the plumbing is hugely varied.

IMHO...don't do it. It's fine as a grey water system, at the minute water is relatively cheap, your not going to see mush of an investment return (if any) and will be putting your health at risk. Filters alone would no remove some of the harmful bacteria, when you get into proper treatment and then paying to periodically have your water tested, filters changed, UV lamps changed etc, etc, it's not worth it.

rampantbunny

DGOBS wrote: »

IMHO...don't do it. It's fine as a grey water system, at the minute water is relatively cheap, your not going to see mush of an investment return (if any) and will be putting your health at risk. Filters alone would no remove some of the harmful bacteria, when you get into proper treatment and then paying to periodically have your water tested, filters changed, UV lamps changed etc, etc, it's not worth it.

rampantbunny wrote: »

I don't have a system installed yet. I started the thread to seek opinions/advice/experience on how I might route water from A to B to C

Thanks DGOBS. Not saying you misquoted me but the whole filtration thing merits a completely different thread (and no doubt there are multiple threads already discussing this topic). My overriding query is about routing the water into the property. Filtration is one aspect to consider when routing but I'll have to sort out the basic plumbing first I think.

Regardless of filtration, I still like the idea of a buffer/holding tank as opposed to direct plumbing into the house. I'll bury the pipes from the water tank as deep as possible (but depth is limited) and probably insulate them to minimize risk of freezing, but something unforeseen might happen along the supply line which means if direct plumbed to house I have no water.


As an aside, and I'm not trying to put the cat among the pigeons here; I grew up in an area where everyone had a rainwater tank because there was no group water scheme. I want to be clear here, I'm not saying categorically that no one ever fell sick because they used/drank their own unfiltered/untreated rainwater, but if they did I'd be surprised if it wasn't "the talk of the parish" such is the nature of small rural communities.
Most people still have their tanks, the difference now is that a mains water supply is plumbed into these and topped up when the tank runs low. But there is still untreated rainwater in these tanks and it is still used as potable water. No tests are carried out. I grew up drinking rain-water that was very basically filtered, not treated, as did my whole family and others around us. The only issue we ever heard of was an outbreak of cryptosporidium after mains water was plumbed in (maybe our water tanks had it all along and we didn't know about it).

Has the quality of rainwater changed in the last number of years to render it unfit for consumption, or has it always been deemed unfit and my whole village (and I'm sure many others) have been playing Russian Roulette of sorts.
Are we maybe saying that you may not have had an issue at time of consumption, but give it some time and it will build up in the body and cause problems later in life? I'm approaching 40 now and waiting for something to kick in. I'm interested in this latter aspect really. If anyone can link to some studies please send them on. I might be happy to risk my own health, but when you have kids perspective changes.

DGOBS

On short, no, nothing about the rain water has changed, neither has the consequences. Birds still pooh on roofs! and it still contains e-coli.

Resistance maybe a large factor, as I remember watching a tv-docu-drama where a number of families recreated the old-west style of living to see what life was like on the frontier. With on 2-3 weeks the show was cancelled as all of the participants got seriously ill, this was due to the unhealthy conditions etc. (such as e-coli) and the final outcome from the scientific community was that peoples resistance to these conditions has altered due to lack of exposure. I feel the same may hold true of this situation.

My better half is an expert in this field, of water microbiology, and I can tell you from her, this is a real and serious danger to you and yours.
Rainwater is not unfit for consumption, it's how it's collected is the issue.

As for Russian roulette, I'd have to say YES thats pretty much it.

rampantbunny

DGOBS wrote: »

On short, no, nothing about the rain water has changed, neither has the consequences. Birds still pooh on roofs! and it still contains e-coli.

Resistance maybe a large factor, as I remember watching a tv-docu-drama where a number of families recreated the old-west style of living to see what life was like on the frontier. With on 2-3 weeks the show was cancelled as all of the participants got seriously ill, this was due to the unhealthy conditions etc. (such as e-coli) and the final outcome from the scientific community was that peoples resistance to these conditions has altered due to lack of exposure. I feel the same may hold true of this situation.

My better half is an expert in this field, of water microbiology, and I can tell you from her, this is a real and serious danger to you and yours.
Rainwater is not unfit for consumption, it's how it's collected is the issue.

As for Russian roulette, I'd have to say YES thats pretty much it.

Fair points. We're digressing, but I sometimes wonder if people are getting weaker. Less resistance, more antibiotics, kids don't eat dirt anymore etc. etc..

Back on point, any opinion on the A to B to C question?

marsbar1

rampantbunny wrote: »

Most people still have their tanks, the difference now is that a mains water supply is plumbed into these and topped up when the tank runs low. But there is still untreated rainwater in these tanks and it is still used as potable water.

It looks as though my tank has been completely bypassed and the flexy pipe from the mains goes straight into the house. You can see the old tank pipe and what looks like a wind up handle water pump (?!) under all the ivy. Tempting to use for grey water then only after reading about treatment costs etc when I redo the plumbing.

my3cents

Brother in Laws family use a stream as a water supply. It's always been grand for them but they run a B&B and had a large number of guests go down with stomach problems. The family had built up an immunity which most of the guests didn't have.

The fix was just a UV lamp system where the water came into the house. Otherwise plumbing was the same as any house on the mains because the feed was from a tank fed from the stream up higher than the house. That was in the UK but I have come across a couple of Irish country homes with the same sort of system.

If you have a source of water then getting it into the house is just a simple plumbing operation really no different from pumping water from a well. All you need is a suitable sized pump and to stop the pump having to go on and off every time there is a demand for water a suitably sized pressure vessel to act as a buffer.

As for the bird **** and crap off the roof you need a first flush diverter on the main down pipe collecting the water obviously that only removes solids and not any water born pathogens. If possible I would also have a settlement tank before the main tank. Provided the water you pump into the house is clear then a UV system should sort out any problems with water quality. Newer UV systems are installed with a cartridge filter system which makes sure the water is clear enough for the UV lamp to work at its rated flow.

So first flush diverter > settlement tank > main storage tank(s) > pump > pressure vessel > cartridge filters > UV lamp > treat like a mains supply from here on.

rampantbunny

my3cents wrote: »

So first flush diverter > settlement tank > main storage tank(s) > pump > pressure vessel > cartridge filters > UV lamp > treat like a mains supply from here on.

So all water, even water for flushing toilets is treated?
Does that volume of water going through treatment:

1. slow the rate at which water enters the house (lowers the pressure)
2. shorten the life of the filtration/treatment system

my3cents

rampantbunny wrote: »

So all water, even water for flushing toilets is treated?
Does that volume of water going through treatment:

1. slow the rate at which water enters the house (lowers the pressure)
2. shorten the life of the filtration/treatment system

The rate is only the rated flow of the filter but that shouldn't matter because normally the only tap that is fed directly of the "mains" is the cold water kitchen tap. The rest of your water will come as it does for a mains connected house from a header tank in the roof, so you are not going to notice if the header tank takes 10 minutes to refill or 15 minutes. You shouldn't notice a pressure drop with a filter. Pressure is so poor in some areas your own pumped supply through filters could easily give you more pressure and greater flow than the mains.

Of course the life of a cartridge filter is limited but if your water is clear coming in then it isn't going to have much work to do. The UV is always on afaik so its life is limited anyway and bulbs are usually rated for a years use sometimes more.

If you were to change filters every 6 months and UV tube every year it would cost approx €150 a year. Then of course you have the UV tube and pump running costs, approx 40-50Watts for the UV tube.

If you are treating some of the water then its just as easy to treat all the water unless you want to replumb all your toilets with a separate supply.

If you check around online you'll find a lot of systems (UV + filters) for household supplies rated at around 12 gallons per minute (45l a minute) and its unlikely you'd want more water than that, many mains supplies would be less.

rampantbunny

my3cents wrote: »

The rate is only the rated flow of the filter but that shouldn't matter because normally the only tap that is fed directly of the "mains" is the cold water kitchen tap. The rest of your water will come as it does for a mains connected house from a header tank in the roof, so you are not going to notice if the header tank takes 10 minutes to refill or 15 minutes. You shouldn't notice a pressure drop with a filter. Pressure is so poor in some areas your own pumped supply through filters could easily give you more pressure and greater flow than the mains.

Of course the life of a cartridge filter is limited but if your water is clear coming in then it isn't going to have much work to do. The UV is always on afaik so its life is limited anyway and bulbs are usually rated for a years use sometimes more.

If you were to change filters every 6 months and UV tube every year it would cost approx €150 a year. Then of course you have the UV tube and pump running costs, approx 40-50Watts for the UV tube.

If you are treating some of the water then its just as easy to treat all the water unless you want to replumb all your toilets with a separate supply.

If you check around online you'll find a lot of systems (UV + filters) for household supplies rated at around 12 gallons per minute (45l a minute) and its unlikely you'd want more water than that, many mains supplies would be less.

Hmm, I see. I will not have a header tank in the house. If I did I wouldn't need the buffer tank in the garage...
Plus no plumbing is done yet so it will never be easier to make provisions for two separate supplies.

Not having a tank in the house means that I either have two separate supplies to the house (one treated, and one untreated) or I treat all the water as you say. I would prefer to only treat what I need to treat. Will have a look into filter throughput.

my3cents

With no header tank how do you get hot water for the kitchen sink, wash hand basin or bath?

rampantbunny

my3cents wrote: »

With no header tank how do you get hot water for the kitchen sink, wash hand basin or bath?

Incoming 'fresh' water is fed through a loop/coil within a tank. The tank itself is heated (geothermal) and heat is transferred to the incoming fresh water as it passes through.
The water in the tank itself is not used for any consumption except to run UFH.

my3cents

rampantbunny wrote: »

Incoming 'fresh' water is fed through a loop/coil within a tank. The tank itself is heated (geothermal) and heat is transferred to the incoming fresh water as it passes through.
The water in the tank itself is not used for any consumption except to run UFH.

I didn't think it was legal to do that with water from the water main? Even if its your own supply any damage to the coil and there is the potential to pollute all your water including whats in the storage tanks with whatever corrosion inhibitors and any anti-freeze thats in the sealed system. The header tank fulfills a whole load of rolls, it prevents water flowing back into the water main or water source, it keeps a ready supply of water, it supplies water at a constant pressure, it can enhance the availability when the mains (or any other source) is at low press or low volume, it reduces water hammer and if you have a pump works with a pressure vessel to reduce the wear on the pump. But I'm not a plumber, I guess that those that are have more sense than to join in on this conversation

My parents have awful plumbing with mains pressure (which is at a high pressure but not at a great flow rate) to all the cold taps and toilets. The water hammer is dreadful, use the toilet at night and the rest of the village can hear the cistern fill back up but after 40 years they aren't going to change anything now.

rampantbunny

my3cents wrote: »

I didn't think it was legal to do that with water from the water main?

What water mains? I've none..

my3cents wrote: »

Even if its your own supply any damage to the coil and there is the potential to pollute all your water including whats in the storage tanks with whatever corrosion inhibitors and any anti-freeze thats in the sealed system.

It's a tried and tested system so I'll bow to the professionals supplying the kit on this one. Allowing fresh water to flow through the coils as opposed to storing the water in a tank means the risk of legionnaires is minimized. The alternative is to keep hot water in your tank heated above 60 deg (I think this is the temp to kill off legionnaires) at all times.

my3cents wrote: »

The header tank fulfills a whole load of rolls...

My garage tank is analogous to this except that it is not in the attic of my house.


Essentially, I'm trying to determine how best to get water from water tank to house. It will be either pumped directly from tank to the house, or (my preference) pumped into a header tank in the garage and then into house.
The garage tank gives me more flexibility and a backup if the source from main supply tank becomes compromised. I can also treat the water in the garage if I want (I've already installed multiple pipes runs into the house for this so they're there if needed).
But my preference means I will probably need multiple pumps because I essentially break the system into sections.
E.g. I'd need a pump from tank to garage..another pump from garage to house. If I treat the water in the garage, and decide to supply that separately that might mean another pump (not sure what pumps are capable of these days).

my3cents

Well their you go another reason for a header tank, it saves the need for multiple pumps.

Joe1919

Dont forget to calculate the actual potential quantity of water that can be harvested before investing. Many parts of Ireland has rainfall as low as 700mm.

I have tried to calculate it in my case. I have a small semi-detached 2 story with a roof area (horizontal) of approx 40 sq meters. So potentially, at a presumed efficiency of 80% and 700mm rainfall, I can harvest 40 X .7 X 80% = 23,000 liters @ 3.7 euro/1000 liters = 85 euro/year

my3cents

In the OP's case he doesn't seem to have any water supply at all atm?

rampantbunny

my3cents wrote: »

In the OP's case he doesn't seem to have any water supply at all atm?

Correct..no supply at moment. Tank built and not as an investment to save money on water charges but for other reasons.

I don't have and will not have a header tank in the attic of my house, period. Time to look at pumps I think.

Joe1919

rampantbunny wrote: »

....Essentially, I'm trying to determine how best to get water from water tank to house. .......

What you could do is treat the outdoor tank as if it was a shallow well and purchase a shallow well kit comprising of a shallow well pump, foot valve, pressure vessel, pressure switch etc. to supply water at 20 -40 psi. No header tank required and high pressure is desirable for filtering. Can be got (not including pipe or cable) for 305 approx from one supplier. Filters and water treatment will be extra.

You would need also some type of float switch to switch off pump in the event of the tank running dry. You could also use this switch via relays etc to activate some type of solenoid/motor valve to switch to alternative water supply. (It would work well for say a supply to toilet cisterns with only a minimum of filtering.)