Have you ever observed how a fall of rain will green up the garden and spark new growth in your favourite plants? Rain water is a great garden tonic, and is especially good during a thunder storm, as it can change nitrogen gas to nitrogen compounds- feed plus water for your plants! Rainwater is a gift in our dry areas, and it makes great sense to save as much as we can for our gardens. With water rates going up, droughts becoming more common, and water restrictions being put in place regularly, the smart gardener will install the largest tank system possible with their budget.
What sort of Rainwater tank do I need?
Rainwater tanks now come in all shapes, sizes and designs to accommodate the needs of gardeners, even the smallest of spaces. Bladders that fit under houses along with slimline designs for those shady narrow alleys where nothing much grows are some of the ingenious new ideas for storing storm water. They can be made from plastic, concrete, galvanised metal, and colorbond steel- each with their own advantages. Some tanks are designed to be installed underground, which can make good sense if you don’t want to take up valuable garden space with a tank.
Some councils offer rebates for tanks, allowing their use in gardens in spite of stringent water restrictions in many parts of Australia.
Another useful way to store rain water are the smaller sized tanks called water butts, which can be rigged up to collect water from sheds, chicken houses and other smaller roof areas. They need a close fitting lid to keep out mosquitos. The larger hardware stores have various designs of them available that can store from 100 to 500 litres, and are cheap enough for people who can’t afford a larger tank system. Even a large plastic garbage bin (new of course!) can be pressed into service for water storage.
Installing Your Tank
Your tank will often come with installation instructions which should be followed for maximum life for your tank. Inadequate preparation of the ground that your tank sits on can lead to splits. The base of the tank will need support across the entire area, and needs to be flat. A tank stand can be a good idea, provided that it is engineered to take the weight- water can be extremely heavy! One litre of water will weigh around a kilo. A stand will give extra height for filling buckets and for natural gravity feeding.
A simple garden tank can be installed by a home handy man, but if it is also going to be plumbed into the house, you should use a licensed plumber. You will need to think about where the overflow will go. It will also need to be the same size or bigger than the inlet piping, so that overflows are avoided. Check with your local council to see what regulations are in place in your area.
The tank will need screening on all inlets to avoid it becoming a mosquito breeding habitat, and it is a wise idea to put in additional methods to screen out leaves and other debris from entering your tank, as this can make your water smelly and dirty. There are various methods available for this, and first flush systems work very well. Cleaning out your gutters regularly will help to keep your water clean too, as will gutter guards. Muck from your gutters is great for the compost bin.