Rainwater Harvesting 101

Let me preface this by saying that harvesting rainwater for the sole purpose of growing plants is as simple as you might think but in the case of self sustainability where the goal is to not pay a water bill, you will want to ensure that your water is always very clean, so in harvesting rainwater there is the issue of water cleanliness that we have to tackle. On a larger scale system, 250 gal to 1000 gal and up, you will need a few components that you can put together on your own.
We will start from the top and move down. You will be using your roof as the source of collection. Obviously you will need rain gutters. Aside from your rain gutters you will first need a 1st screen that will keep larger debris from entering your storage tank. Directly connected to downspout of your rain gutter(s), you will need a first flush diverter. The purpose of the diverter is to trap the rest of the unwanted debris such as dirt, other sediment and floating particles such as leaves separately from the clean water. Its basically a pipe with a floating ball or plastic water bottle in this case, inside of it, that once full, will plug any more water from entering, and diverts it to the next stage of filtration.
This video details exactly how you will need to build it, minus the overflow. Thats just extra money spent and i dont recommend adding it unless you absolutely have a dire need to divert that water away from your house.

This is my first flush diverter i built, based on the video. It cost me 145$ for the pipe and fittings you see pictured here but its a long term investment that will pay me back over and over again.
5.5’ of 4" pipe with 2 couplers, 2 reducers down to 2", another coupler for a screw on bottom, 1- 2" T, 3- 2" 90° elbows. The water bottle goes inside the 4"pipe and stops the inflow from the top once its floated.


From the first flush diverter we move to the slow sand biofilter. This is really the last step of filtration that you need. This is a filter that utilizes naturally occuring, beneficial microbes, gravel, and sand to filter your water to a surprisingly excellent water quality. Better than tap water, well water and RO water. You simply need a 5 gallon bucket or larger depending on how large your system is. Will post 2 videos that use different size containers, one of which was made by me which demonstrates how well it can remove calcium carbonate and anything else that drives up your ph. I appreciate the views ahead of time. Your lower layer of filtration is gravel. This is your drainage layer. You add your outlet plumbing below the top of this layer which will need to be directed back up, but below the overflow level, before exiting. Above that, in my filter, i added a 1/4" layer of homemade biochar for carbon filtration. Above that layer is play sand which works exceptionally well as the mechanical filter as you will see in my video. You have to install some sort of device that will ensure that your water level always stays above the level of the sand. This is important for the “biofiltration” aspect of the slow sand biofilter. The highest level of sand in your filter actually houses the beneficial microbe population which will filter out, by way of eating, any anaerobic microbes, e-coli, cholera, and any other type of pathogens that you do not want to be drinking. In my SSBF i use a small 10 dollar submersible pump with a pvc overflow that overflows the unfiltered water right back into the reservoir to keep my water level above the sand as well as it keeping the water surface breaking at all times for extra aeration. Additionally, i added an air stone and a small aquarium air pump into the reservoir as well. The filtered water, you will want to store in a light impermeable container and you can use it as you need it for drinking or otherwise. You can make this system as intricate with a reservoir and a pump to your running water system or as simple as the one i designed, either way that pretty much covers everything you need to know for safe rain water harvesting. Hope this helps you guys be more self sufficient out there. Devalue the american dollar by keeping it out of as much of what you do as possible. Happy growing.

My smaller sized ssbf i designed.

A larger scale design

Check it out gents i finally got around to the rainwater topic.


Very nice dude


This. Is. Amazing! What a great post @BrayneGro!


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