Whole House Rainwater Cistern Water System




We live out in the rural area, too far from the county water lines, and the water tables are polluted because of old oil wells. We built our house in 1997, with this current water system. at first, the water was pvc piped into the house, but after the first winter when the lines froze and broke, we came up with the current hose circulation system to prevent that. It's been 4 F actual outside temperature and the water hasn't froze! The only time we had a problem, was the ice storm of 2007, when the power was out for a week. The circulation pump in the tank couldn't pump, so the water did freeze. If we would have had a generator in place, this wouldn't have happened.
The main water tank outside is 1500 gallons, the reserve tank is 400 gallons. We get about 600 gallons to 1 inch of rain from our roof space. The main roof is 20' x 48', the second story roof is an additional 16' x 20'. We have water flow restricters and a low water flush toilet in use in the house. It's just like the city, but the water comes from the rain, not a pipe via the water treatment plant. Our area receives enough rain to get us through the year. The reserve tank is usually pumped into the main tank in late august to tide us over the end of the dry summer in Oklahoma. I don't have a washer or dryer at the  house, i go to the laundromat in town. If we put in a larger tank, we could support a washer, we get enough rain, it's just something we've never bothered doing as laundry isn't my favorite thing. I can get a week of laundry for 4 people done in 2 hours at the laundromat, i find that easier.
The water goes through a whole house filter before it goes into the main line to the rest of the house, we also add some regular bleach to the outside tank occasionally. The water is so soft, that soap and shampoo wash away quicker than with water from the city. The sinks and bathtub are on separate drain lines that go out to the front brushy area to reuse the gray water. The toilet goes to a modified septic leach pond area. 
I think I labeled everything so it is easy to understand, I had to ask my husband to help me label all the parts as I'm not the plumber.
I hope this will help other people who live in areas without a water line to hook into, or those who can't have a well due to polluted water tables.
Post any questions, i'll try to answer them. Thanks for checking out my instructable!



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    12 Discussions


    9 months ago

    Are you rain gutters the same type you'd get at the hardware store? Do you have photos of how the pvc pipes are attached to the gutters? Thanks

    1 reply

    Reply 9 months ago

    they are just screwed onto the spout.


    1 year ago

    I know this post is kind of old, but I also live in Oklahoma. We are building a house in the North Central Oklahoma area, and since first of all we will be in the middle of no where, and second, I worry about drought conditions and a water well, and third, when it rains here it RAINS, I figure why not use it! I have manyyyyy questions for you!!

    When I moved here 5 years ago, Oklahoma was in the midst of a huge drought. How did your system fair? On average how much rain do you collect a month?? How low do you get water wise with no rain for a month??

    1 reply

    Reply 1 year ago

    we've never run out of water due to lack of rain, it was a pesky raccoon that pulled out the circulation lines that drained the tank! annoying things. after that we secured it better and haven't had any problems. as it says above, i've measured it at about 600 gallons to 1 inch of rain. in the last few years, we've had to pump over the reserve water in the winter, since we've been having dry ones lately. we could easily fill and maintain another 1500 gallon tank, but lack of extra cash has put that on hold. we do fill 1 gallon water jugs at the ice house for drinking water, we got so used to that when i was making baby formula that we like the taste of the water better. my parents are also on a similar system, they use one of those britta pitchers for drinking water. i grew up drinking the water, and never had any problems. i do use the water for cooking. we're pretty frugal with water usage, navy showers with water flow restrictor, not flush the 1 toilet we have every time unless it's #2. if you have any more questions, let me know.


    3 years ago on Introduction

    Whats the square footage of your roof? At the very least whats the foot print of the structure you are collecting water off of?

    1 reply

    5 years ago

    at the time we bought it, $500. now it would be about $1700, I think.


    5 years ago on Introduction

    If I had more time I would make one too. Thanks for making this and posting it.