Installing an underground water tank may be the first step you take in setting up a rainwater harvesting system for your home. This can make you become partially self-sufficient in water and save you the bother of looking at unsightly tanks all day. If you are saving water, you will also be helping to secure your local water supply, which is under constant threat from drought and variable rainfall. Burying your water tanks underground also has the added benefit of saving precious space, particularly in an urban setting where every square metre counts. Popular sites for an underwater water tank include under your driveway or in your back or front yard.

Modern construction techniques now mean that concrete water tanks are a lot lighter than their previous generation. Concrete tanks are typically reinforced with steel for maximum durability. These are either precast and able to be delivered to your property for immediate installation, or constructed on site to your desired dimensions.

Why concrete?

Concrete underground water tanks have many advantages over other materials, including:

• inherent strength making them naturally rigid
• durability with no danger of rusting, corroding or being damaged by tree roots
• available in a variety of different sizes
• not liable to ‘float’ like a plastic tank may
• concrete is made from natural materials and is therefore easily recycled
• save space by burying your tank underground
• keeping your water cool

Water tank checklist

If you are considering installing an underground water tank, use the following checklist to plan your project, backed up with advice from your supplier:

• check for details of any local government tank rebates on offer, which are designed to offset the cost of installation.
• check with your local council regarding regulations governing the installation of water collection tanks in your area
• determine the cost of the project including plumbing and installation costs as well as ongoing maintenance
• the size of your roof will determine how much rain water you can collect, and therefore what size tank you can have
• select a suitable site for your tank
• make sure your installer checks for underground obstructions before digging starts

If you are considering installing a concrete underground tank consult a supplier or green plumber on this site, for further advice.