Rain water Recycling System

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Rain water Recycling System

Post by CanaBalistic » Mon May 25, 2015 10:32 pm


This is a complex rain water system i'd like to build. Unfortunately I can't build this system now as i am a renter. I am however looking to buy a somewhat run down house and fix it up for my fiance and myself and employ it there.

This is a multi purpose system that i feel is beneficial not only for the prepper but also for the environment. It allows storage and use of rain water for showering (biggest waste of drinking water) and also recycling of that water to run a toilet. This helps alleviate unsanitary conditions in the event of a disaster or pandemic where people might wish to stay inside. This would also be a great idea to install at a cabin just to have water available.

Water System.jpg
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Water from the roof runs into a first catch device. It then fills the 275gal rain water totes. There is an overflow that would redirect water to the grey water tanks if rain flow is heavy enough. Water is then lightly filtered and pumped to shower head, outside spigot and through a heavy duty filter at a sink for potable water. Bathtub drain also flows into grey water tanks. The grey water is lightly filtered and pumped to a toilet. Waste is then ejected into the sanitary line.

Not pictured here is another system i'm trying to figure out which would use city assist. This would detect when the tank levels fall (summer drought) and turn on a city line feed to fill the tanks to 1/4 full. This ensures there is all ways water in the tanks but makes the most use of rainfall and not city water. There would need to be a similar system in the grey water tanks which would probably pump from the rain water tanks.

Any questions or comments?

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Re: Rain water Recycling System

Post by CanaBalistic » Tue May 26, 2015 5:48 pm

I should have also noted that the punps could be run off solar panels

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Re: Rain water Recycling System

Post by helicopilot » Wed May 27, 2015 6:50 pm


I'm not an engineer nor very technical type of individual. Everything made sense to me until you brought it city water in the mix, then all derailed in my mind. If you plan on being hooked to utilities, then why bother with all the extra expense? I could see this plan working for a remote location or even is some subdivision not serviced by town water and where we'll water is mediocre. Then instead of relying on city water, you would consider larger cistern that could be topped up by trucking in potable water as needed.

On the other end, if you are willing to go through the expense, this is a commendable environmental endeavour.

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Re: Rain water Recycling System

Post by thecrownsown » Thu May 28, 2015 4:01 pm

Its a great idea. But it needs to go further. :)

-This looks like a general intent but you need to look into the details to prepare a design. There's no specifications on materials (pipes, etc.), fixtures, filters, etc. No design for water balancing, no venting of drain lines, pump design or calculations missing. I'd recommend getting in touch with someone in your region who does this and is familiar with the plumbing codes, and green initiatives.
-I dont see a connection in the diagram to City water. If your going to run waste water to city services they are most likely going to ding you for providing city water as that's where its typically metered. Perhaps a septic field or another method to dispose of waste water?

This is a great idea. And as Helicopilot says a commendable environmental endeavour. There are systems on the market like this for commercial applications, so probably pre made models for residential also. But like a lot of green initiatives...very pricey. If you can put something together on your own, kudos to you!

Enermodal Engineering in Waterloo has a system almost identical to your proposal. Its a full 2 story commercial building with rain water collection on the green roof, grey water use in toilets, cisterns for water collection...even the lawn in front of the building is drought resistant and doesn't require watering. They use approx. 9L of water per building occupant per day. Considering a toilet would run 4-6Lpf 9L is an insanely low number! http://www.sustainablewaterlooregion.ca ... t-trick-2/

Your on the right track! :)

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Re: Rain water Recycling System

Post by CanaBalistic » Fri Jun 05, 2015 5:42 am

I'm trying to polish this idea. This would be more suited to urban areas, small cabins due to its size. A large cistern could negate the whole grey water aspect of this although they are quite large. I cant see anyone in the city putting a 1000 Gal cistern in their back yard. This system is small enough to fit inside a garage or shed, due to its small size. Its also easily expandable.

A city assist feature helps ensure there is always some water in the tanks during drought or when there is too much demand on the system. It would focus on rain collection but could maintain function though a city connection if available. A float valve could be set so that the tank will never fill past 25% on city water. (You'll never run out of water and will save thousands of gallons of city water.) Instant off grid capability in a SHTF scenario.

Here's what I've got so far in sketch up.

Left side is rain water, right side is grey water

*The height of the rain tank creates a back flow preventer to the grey water tank through the S pipe, excess would drain into sanitary line (septic field preferably). A P-Trap and vent could be added if required.
*The filters shown would be mesh filters with drains on the bottom. 500 mesh then 1000 mesh. This ensures the pumps don't suck up anything too big that could cause damage.
*Rain water would pump directly to spigot (for outdoor use) and shower through instant hot water heater. Another filter (not shown) would filter water for domestic consumption.
*Shower basin or tub drains to grey water tank. As showers consume the most water, this should ensure an adequate supply of grey water
*Grey water is filtered through mesh filters again to prolong pump life then goes to toilet. Toilet drains to sanitary line or septic field.

I hope this explains everything. Please let me know if you have any more questions or concerns.
Rain Water System with shed.jpg
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Re: Rain water Recycling System

Post by tradesman » Fri Jun 05, 2015 7:39 am

I've looked into the designs at earthships housing and it's a complete system similar to your design. Proven over years of testing it may give you some ideas. I'm speaking of the plumbing aspects and not the entire home architecture.
Here is a link: http://earthship.com/

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Re: Rain water Recycling System

Post by The Island Retreat » Sun Dec 27, 2015 9:23 pm

Glad you put the totes on blocks. Enables gravity feeding as a backup. Engineer 775 on YouTube goes into the first flush system in great detail too. I am planning on building a much smaller idea about 20 miles west of you on the island. Perhaps we should collaborate? It might help you figure out what not to do, at least. I have 30 blue barrels currently unemployed on the doomstead. My plan includes a higher up main supply, a 3 position 3 barrel setup, and 'recovery systems' (read rain barrels:) for the coops.

Come springtime, if you're on the island, drop a pm!
Check out Canadian Prepper Podcast on iTunes!

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