When planning out your homestead make sure that you don’t forget to make room for a simple rainwater catchment system. They are great for watering the gardens and to have as an emergency backup if needed. Rainwater harvesting can provide a water supply during restrictions and can help supplement your monthly usage.
Although rainwater is potable I would still properly filter and process the water coming out of a catchment system to make it 100% safe for drinking. Metal is preferred for a roofing material to collect the water but one thing that is often overlooked is the gutter system. If you plan on using the water for drinking or cooking it is imperative that you clean your gutters regularly and install a diverter system for the initial rainfall. With a properly installed system you can theoretically capture .6 gallons of water per inch of rainfall. So for a 20×40 roof like ours; we have the potential of collecting 480 gallons between our two totes with one inch of rain. You can see how we built ours below.
1. Check Craigslist for 275 gallon totes, we paid $75 apiece for ours.
2. Set the totes side by side and check for level.
3. Excavate as needed.
4.Use a threaded disconnect to connect the totes and add a spigot.
5. Run a 4 inch pipe from the gutter to the totes.
6. The system is basically complete.
7. Add a hose reel to make watering the garden easier.
With our system the tote on the right fills first which then fills the second tote through the piping on the bottom. This allows us to flush the system of any debris that may have collected. We simply fill the first tote fully and then open the valve on the second one which cause the water to rush through the system and forces a majority of the debris into suspension. We then remove the disconnect valve and drain both containers; it’s not perfect but it works for our needs.
Below are a couple thoughts after having the system for several years now:
- Check local laws about capturing rainwater, it is illegal in some states.
- Add some bleach and let it set overnight before draining for the season to control any algae blooms.
- You need to protect the totes from UV light; it will cause them to degrade.
- Make sure whatever container you use that it was previously used for food grade materials.
- Make sure the totes are higher than your garden to increase water pressure.
For further information the Texas Water Development Board put together an excellent rainwater collection manual as seen below. Good luck with your planning.