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logguy
12-22-2009, 09:04 AM
I have this idea of a rain water recovery system that uses inexpensive 50-gal drums, one solar panel, and an electric water heater. I think that this system will allow a family to have a full day of hot and cold water, replentishable through the daily use of a hand crank pump. This system could be used daily, indefinately, much easier if you replaced the hand crank pump with an electric pump that would keep the second floor primary storage containers continuously full. I think this would provide an unlimited amount of water for an average family if you had enough first floor secondary storage 50-gal drums. Our family uses the refrigerator door drinking water recepticle for our drinking water. This recepticle and one additional water faucet at the kitchen sink, both connected directly to the well/city water source, is what I feel comfortable with.

rreidnauer
12-22-2009, 10:15 AM
You are on the right track, but there are a few things that need to be worked out.

1. You'll need a much larger pre-filter than illustrated, as well as a dump diversion device which would spill off the first several gallons of water before transferring to storage, as you want to "wash" the roof before collecting.

2. Water stored on the second floor will only provide slight water pressure on the first. Water pressure is roughly 0.5 PSI per foot of head, so water stored a floor above (say 9 feet) is only providing 4.5 PSI. Typically, you want at least 35 PSI in the home. Some devices (like a dishwasher) with electric solenoids may not function properly at low pressure.

3. Your shut-off valve in conjunction with the hand pump will have some problems. Namely, a build up of air pressure. With no where for air to escape, you won't be able to fill your tanks. You will need a place for air to escape, and the best solution may be an overflow line back to the pump area. Just pump until water starts returning. Your idea of an electric pump in conjunction with one or more diaphram well tank(s) would resolve both your water pressure and storage concerns, but you'd have to have your catchment system run straight to your storage tanks in the basement.

4. The solar panel. I'm assuming you are talking about a solar-thermal panel, and not a solar-voltaic panel, yes? Electrically heating the water will fail miserably, but a thermal collector will work good. I prefer vacuum tube collectors over flat plate, and closed loop over drainback. The vacuum tube collectors will be able to convert more light energy to heat, because a) they have lower heat loss and b) collect energy at a consistant rate even if the sun is at an angle to the panel. This will be very important on those partly cloudy days. They are misunderstood by most people who never studied them. Water never enters the tubes themselves. It is contained in a manifold at the top only, leading to far less chance of leaks. I recommend closed loop because it eliminates the freeze potential, eliminates corrosion possibilities of exposing the interior piping to air, requires a much smaller pump since there is no head pressure. However, you do add to the cost of the system by adding a heat exchanger and antifreeze. (non-toxic and specifically designed for the high temperatures of a solar collector system. DON'T USE RV ANTIFREEZE)

5. You drum storage would require a daisy-chained bottom piping as well. While excess water will flow from one to next as you have it shown, you wouldn't be able to extract the water back again unless you're planning on moving the pump from one barrel to the next. In any case, I'd rather have a single, concrete cistern (perhaps with a plastic bladder) versus all those barrels, but to each their own.

Like I said though, you're on the right track, and a little experimentation is required for those unanticipated problems you don't count on.

donjuedo
12-22-2009, 01:54 PM
Texas published a manual for just this sort of thing, and I just download the 3rd edition from here:

http://www.twdb.state.tx.us/publications/reports/RainwaterHarvestingManual_3rdedition.pdf

It is good reading. There is much to consider, but for me, this is the way I'll go with my last house.


Peter

logguy
12-23-2009, 12:32 PM
Texas published a manual for just this sort of thing, and I just download the 3rd edition from here:

http://www.twdb.state.tx.us/publications/reports/RainwaterHarvestingManual_3rdedition.pdf

It is good reading. There is much to consider, but for me, this is the way I'll go with my last house.


Peter


WOW--THAT's good info!!!

The roof flush system really makes me want to scrap this whole idea and just do this simply and unfiltered on a metal barn roof.

Too bad about the pressure issues too. I wonder if there is an easy, inexpensive pressurizing unit that I could impliment into my system.

I like the 50 gal drum idea, personally, if I could buy them cheap enough. We have a guy here locally who sells plastic soft drink drums really cheap.

donjuedo
12-23-2009, 03:17 PM
You may be able to get those drums for free. I did. I located a brewery, asked, and they gave me all I wanted, 2 or 3 at a time. They buy drums of a cleaning acid for the beer containers (vats?), and when the drums are empty, they dispose of them. Mine are polyethylene, complete with caps.

I also tried Kraft foods in Winchester, Virginia, and they do indeed go through a large quantity. But they give priority to employees, who have figured out they can sell them on ebay and elsewhere. :-)

My brother worked in industrial gases, as in liquid nitrogen to freeze McNuggets and the like. He told me about food processors in general, how they use 50/55 gallon drums day in and day out. After a little time with Google, I found Kraft (above), so you could try the same approach where you live and find free barrels/drums.


Peter

logguy
12-23-2009, 03:25 PM
You may be able to get those drums for free. I did. I located a brewery, asked, and they gave me all I wanted, 2 or 3 at a time. They buy drums of a cleaning acid for the beer containers (vats?), and when the drums are empty, they dispose of them. Mine are polyethylene, complete with caps.

I also tried Kraft foods in Winchester, Virginia, and they do indeed go through a large quantity. But they give priority to employees, who have figured out they can sell them on ebay and elsewhere. :-)

My brother worked in industrial gases, as in liquid nitrogen to freeze McNuggets and the like. He told me about food processors in general, how they use 50/55 gallon drums day in and day out. After a little time with Google, I found Kraft (above), so you could try the same approach where you live and find free barrels/drums.


Peter


You are the man!!!

donjuedo
12-23-2009, 03:32 PM
:-D

rreidnauer
12-23-2009, 06:33 PM
The roof flush system really makes me want to scrap this whole idea and just do this simply and unfiltered on a metal barn roof.

Too bad about the pressure issues too. I wonder if there is an easy, inexpensive pressurizing unit that I could impliment into my system.
Roof flushing is not that hard of a thing to overcome really. Here's a few ideas (http://www.reuk.co.uk/First-Flush-System-Rainwater-Harvesting.htm) how to deal with it. Additionally, prefiltering can be easily dealt with by using a couple of those 55 gal drums filled with a course sand for the water to run through before going to whatever filtering system you choose to use.

As for pressure, does your property have any slope? Placing your holding tanks 70 ~ 130 feet uphill connected to the house via a 2" line would give you 35 to 65 PSI off gravity alone, though you'd still have to pump water up to the tank via whatever method you'd choose. Of course, if your catchment is at the holding tanks, no pumps are required. I thought about hanging a tarp with netting (like used in orchards?) suspended over it to work as a catchment device while keeping most debris out. Unfortunately for me, I don't have the required slope for a self pressurized system. (unless I build a water tower) I'm thinking about using a common RV demand pump (or home equivalent) for pressure.

andrew mason
04-11-2010, 06:30 PM
for pressure, if you are storing your water on the 2nd floor... assuming that the containers are sealed, rig up and air compressor, and create a pressure air bubble.
that will help the pressure issue... what i cant help you with is the following... how much pressure you will need, and how offten you will need to repressurise, wich i think will be offten.

StressMan79
04-12-2010, 11:31 AM
if you get a shallow well pump, there is a bladder, etc already built in. Your pressure is taken care of. Otherwise, you will need at least 30PSI dedicated compressor, and without an expandable bladder (say a rigid cask), you'd need a huge capacity whenever you turned on the water, as the pressure would drop almost immediately.
If you have AC You can get a cheap pump that will do all this from HF for 100 smackers. dunno how long it will work, but at least you have the tank/bladder/pump. I don't forsee the bladder rupturing or the tank leaking, if the motor goes out, you can replace with a better one ;), maybe even DC for guys like Rod and Me....
I would do as rod suggested with the drums, if you have an 8' drip line, you can stack two on top of each other, and then two side by side, do your filtering (2"/ 1"/0.5"/0.25" at 5" intervals, you;ll then fill up the bottom 20" of the drum, the rest for surge) in the top drum, storage in the bottom drums. Daisy chain together as many storage barrels as you need with some 1" brass hardware and some potable PEX tubing, and you'll be good to go.
This is sposed to filter for biologicals, but I would still use a UV system in my home at drinking oulets or use a bit of bleach in a pinch. Not really worrired about the stuff coming through the filters, but growing in the systern. You may want to shade the units so that you don't get any algae growing in there too.
*I may have to do this*
-Peter

rawson
04-12-2010, 06:41 PM
Not sure if about the pressure pump with a built in bladder. I recently purchased and plumbed a jet pressure pump 20 psi ON to 50 psi OFF, that pumps into a pressure tank with a bladder to sustain pressure. This bladder tank holds 50 gallons of water. The storage is from a 3,000 gallon concrete holding/storage reservoir that the Well pumps into. A nice setup to prevent too much on and off cycling of the Well pump.
If a sand or gravel pack filter is plumbed into a roof catchment system it should be plumbed for backwash cycles or it will eventually plug off or need to be repacked it would be advisable to occasionally treat with NSF Chlorox bleach target dosage 6/7 drops per gallon to achieve 1 part per million safe levels for human consumption but wil slow slime growth and disinfect the filter. It should also be mentioned to route the roof water into a standpipe with a small hole drilled into the bottom of the pipe to waste the first flush indroduced as the first rain fall water is collected this will waste the dust/dirt/bird droppings etc...then as the pipe fills to a larger diameter hole that water is routed to the storage barrels.
Keep in mind all the water on this Earth has passed through a living creature at some point in time!

logguy
12-27-2014, 02:04 PM
Thanks, all. That's good stuff. I've got two totes set up on the north side of my barn (if I can remember how to post a photo I'll do it) for use to water the sheep, rabbits and chickens. And the friggin duck. I don't recommend ducks, but I digress...

I just posted another thread asking for help with making my tote collection system a continuously flowing system during the winter months, incorporating an old hot water heater as storage for a solar collector, fed by one if the totes, gravity (hot water heater is 13' up in the top of the barn) and hot water circulated naturally (or through the use of a low pressure pump w/pressure regulator if it doesn't move on its own fast enough after I spin it up with an inline pump to get the air out and everything flowing once all is connected).

logguy
12-27-2014, 02:46 PM
2634

Here are the totes connected.

oldditchdoctor
02-07-2016, 11:29 AM
We have a guy here in SC that gets the square 235 gal. totes that are food grade. He buys them from a local bakery, they are used to store honey, just a thought. The 235gal. are about the same price as 2-55gal., and they have a metal "cage" and are liftable with a forklift if need be. That would allow for placing at a higher level for more psi.

rawson
02-07-2016, 05:11 PM
Those food grade totes are great. Got four on this site, plus 8 - 55 gallon food grade HDPE barrels. Check water treatment facilities sometimes they can not get rid of these and will give them away, that's how I got mine.