Can I install a cheap rainwater harvesting system?
If you are very good with DIY and are comfortable with water pipe fittings and pumps, then it may be possible for you to install a cheap above ground system for watering the garden. There are some great examples of DIY rainwater harvesting systems on YouTube – some with quite good filter systems. However when it comes to underground rainwater harvesting systems, and systems for using water in the house, it’s better to invest a little more money to get something robust.
Some points to consider when buying a rainwater harvesting system are:
- Is it a shallow or deep tank? A deep tank will be dangerous if you ever want to remove the pump, and will be harder to install in the ground, costing you more in earth excavation, time and larger plant machinery. It will also increase the risk of hitting water in the ground.
- How wide is the opening in the tank? A narrow 450mm opening will be very difficult to get into, especially if there is a filter in the tank. A 600mm opening is better.
- Quality of pump – a good pump from a major pump manufacturer is best.
- Level of filtration – here, the more filtration the better! A few little bits of grit coming through the system will cause havoc to your toilet valves.
- Quality of mains water back up – using industrial brass magnetic valves is preferable. Some of the cheaper packaged boxes use low-quality valves which are prone to failing.
Take home message
We really encourage people to save water and making your own rainwater system is a great idea if you just want to use it for the garden and have the relevant skills to do so. But don’t do this for toilet flushing as you could cause yourself a lot of problems, you could even without knowing contaminate your drinking water supply!
Last Update: December 5, 2019