There aren’t many consolations to a rainy day– cosy couch time, soothing sounds of water on the roof, and possibly a rainbow or a puddle-splash afterwards. But you can add one more by building a water tank to capture a bit of that downpour: it’ll diminish your environmental footprint by reducing your demand on mains water and the quantity of stormwater runoff into rivers and oceans, and can also slash your water bill in the longer term.
Rainwater tanks are no longer just huge, round and bad-looking; they come in all sizes and shapes that can make efficient use of small or tricky urban spaces.
Water for outdoor or indoor use?
The most important issue to consider before you acquire and install a rainwater tank is how you would like to use the water.
Applying the water outdoors– for watering the garden and washing the car, as an example– is the best way to start, as you most likely just need the supplier to set up the rainwater tank, as opposed to a licensed plumber. And it will promptly cut your consumption of mains water.
Save even more by sending the water to your toilet, washing machine or hot water system, but you’ll require a licensed plumber to connect the water tank to your mains supply.
What size water tank do I really need?
The storage capacity you choose will depend on the size and shape of your household and garden. Round, squat tanks fit efficiently under a deck, while slimline tanks are good for narrow spaces. An underfloor tank or bladder storage system is a good out-of-sight space saver, however is more expensive.
Your roof area and the annual rainfall in your location will also need to be considered. To help determine the size and shape that’s best for you, sellers often provide calculators on their web pages, or your water authority may be able to help.
What else do I need to understand before purchasing a water tank?
Water tanks usually come in the following materials:
Metal tanks are made from corrugated or flat rolled metal, which can be galvanised or coated. They often include a plastic inner lining (Aquaplate) that will enhance the quality of life of the tank and give protection to the water quality.
Polyethylene (plastic) tanks are popular as they are fairly cheap and durable. Because rust isn’t an issue, they are a great option for people living near the ocean. Other synthetic materials, such as PVC and geotextile, are applied for bladder storage. Bladders work for water storage below a deck or floor; while their material is durable, it’s not intended for outdoor installation.
Fibreglass tanks are rust and chemical-resistant and developed to withstand extreme heat levels. They’re not the cheapest possibility, and preferable for above-ground installation, while all other types can also be set up below ground.
Concrete tanks, more often used for agricultural and industrial intentions, won’t rust, burn, melt or blow away. They could be bought ready-made, or custom made onsite.
Ask your local council and water supplier which rules and regulations apply in your area. You may need to provide a development or building application, and there may be policies around drinking rainwater or mosquito breeding prevention, along with restrictions on the tank’s specific location, colour, height and labelling or noise regulations for a pump.
Are you remodeling, building new or retrofitting?
If you are renovating or building, in lieu of retrofitting, you may have to incorporate energy and water-efficient elements in your plans to satisfy new legislative requirements.
When securing quotes, ask if there are any further costs for delivery and installation; extra materials (such as pipes, fittings and taps); optional extras (such as a first-flush or backflow-prevention device); a pump (unless you can work with gravity for water pressure); and a stand (unless you want to put it on the ground or below it, by which case you’ll need to think about the cost of special ground prep or excavation).
If you intend to connect the tank to your mains water supply, factor in the cost of a licensed plumber, and costs for any extra work that needs to get done to your roof and/or guttering.
Can you get a water tank rebate?
Contact your local water or government authority to see if you’re entitled to a cash grant or bill reduction– the answer may depend upon the size of the rain water tank and whether it’s connected to a toilet and/or washing machine.
rainwater tank pump tanks can fluctuate from around $700 to $2000, starting from a small, freestanding model without pump or extras, to large, custom-built models. Costs vary basing on the size, material, finish and strength of the tank.