The many benefits of rainwater tanks
Did you know that 1 in 4 Australian houses have rainwater tanks installed? In recent years, harvesting rainwater has surged in keeping with householders’ conscious efforts to do their part for the environment. The increased adoption of rainwater harvesting is unsurprising given its benefits - reducing water bills, lessening flooding, and mitigating water pollution.
How does a rainwater tank work?
A rainwater tank collects rainwater from a catchment area (usually the roof) which flows through the pipes and into the tank. This will funnel into internally connected fixtures. When needed, the rainwater is distributed from the tank to various points of use, such as a garden tap, toilet cistern or washing machine.
A pump is often required to distribute the rainwater to its point of use. The pump may be connected to a pressure switch or other control system to ensure the water pressure is consistent and reliable. Once full, the excess water flows into the stormwater drainage system.
What are the different types of rainwater tanks?
Rainwater tanks mainly come in four different materials. These are:
- Plastic or polyethylene: These are placed above the ground, are lightweight, durable and easy to install.
- Steel: These rainwater tanks are robust and durable. They are also easy to install as they are lightweight and placed above ground.
- Concrete: Can be placed above or below ground and are sturdy. Because light can't penetrate them, they can store rainwater without algae growth and keep the water supply cool.
- Fibreglass: These tanks resist chemical corrosion and rust while tolerating extreme temperatures. Fibreglass tanks are type placed above ground and come in a range of colours, shapes and sizes, making them a popular choice for homeowners who want to save water while keeping their home looking good.
What are the benefits of rainwater tanks?
Reduced water bill costs
Having a rainwater tank reduces reliance on the mains water to supply the household's water needs. You can easily lower your water bills - especially if you can use tank water for the most water-consuming tasks. Depending on how much rainwater your roof can capture and tank can store, you can get the best value for money if you use harvested rainwater for flushing toilets, doing your laundry and gardening.
Great for the environment
Harvesting rainwater lessens the strain on waterways, which reduces the likelihood of local flooding. This decreased amount of heavy stormwater runoff translates to less damage, less soil erosion and less pollution to local bodies of water.
More people adopting a rainwater tank system also reduced demand on reservoirs or dams, extending the general population's access to fresh water in dry seasons.
Greater flexibility with water restrictions
Rainwater tanks are good news for your garden. One of the biggest benefits is being able to use the water collected in your rainwater harvesting system during government water restrictions.
Purer water
Harvested rainwater is ideal for cleaning cars and windows because it lathers better. Rainwater tends to be softer than tap water because it has a lower mineral content. Rainwater is naturally distilled and does not contain the minerals and other impurities that are commonly found in tap water, such as calcium, magnesium, and iron. As a result, rainwater tends to have a lower pH and a lower level of dissolved solids than tap water (depending on your region).
Rebates
In some states and regions, homeowners may be eligible for a rainwater tank rebate through either the state government or the local council. Schemes in South East Queensland, have previously offered $1000 rebate for rainwater tanks, pumps and diverters, and installation. Check with your council or state government authority.
Backup water supply
If you do not connect your rainwater tank to the mains system, it can still serve as a reliable backup. When water levels are low or restricted, or if there are issues with the main supply, having a backup water source can be invaluable. By collecting and storing rainwater, you can prepare for contingencies and have a supply of water readily available when needed.
Adds value to your home
A rainwater tank has become a quintessential feature of the Australian dream home, and many modern houses incorporate them into their design.
Moreover, rainwater tanks play a crucial role in boosting the water efficiency of a property. As a result, many real estate listings highlight them as an attribute. By providing both aesthetic value and environmental sustainability, a rainwater tank can enhance your home's worth and appeal.
How to choose the right tank for your home
Many factors can determine which rainwater harvesting system will work for your home. First and foremost, the tank size should be appropriate for the amount of rainwater you intend to collect and the size of your property. It is essential to consider the material of the tank, as different materials have varying levels of durability and resistance to UV rays.
Additionally, measure the available space and calculate your desired usage to help determine the best size and positioning.
Other features to think about include the inlet and outlet placements, the type of filtration system, and whether the tank comes with any additional accessories or warranties. Ultimately, it is important to research and compare different options to find the rainwater tank that best suits your needs and budget.
How big should your rainwater tank be?
There are a few factors to consider for tank size: the climate in your area (average rainfall), general usage, roof size and space/location restrictions.
The general formula to gauge the size of your tank is to multiply the area of your roof by the average rainfall in your area. This represents the maximum amount of water you can expect to capture.
Amount of water captured = area of your roof x average rainfall in your area
You would also need to calculate how much water your household uses daily to determine how much of your usage can be covered by your captured water. Remember, tanks don't necessarily have to be bigger, especially if you live in an area with frequent rainfall!
Do I need council approval to install a rainwater tank?
The need for council approval to install a rainwater tank varies depending on the location and regulations of the specific council. In some cases, installing a rainwater tank may require approval or a permit from the local council, particularly if the tank is large or if the installation involves major modifications to the property.
It's important to check with your local council or building authority to determine the specific regulations for your area. Your council may have specific guidelines for rainwater tank installations, including minimum distances from property boundaries, rules on tank placement, and other requirements.
It's a good idea to consult with a licensed plumber or rainwater tank installer to ensure that your installation meets all relevant regulations and standards, even if council approval is not required. This helps ensure that your rainwater tank is installed safely and efficiently and that it is properly integrated with your existing plumbing and water systems. Licensed plumbers can cost anywhere between $80 and $160 per hour.
How do you install a rainwater tank?
Once a plumber has chosen a suitable garden section for your rainwater tank, they'll prepare the area, ensuring the ground is flat and compact (if installing one above ground).
Once the tank is in place, the plumber will attach the inlet and overflow pipes to the tank and connect them to the downpipes from your roof. They will also need to seal the tank tightly to prevent any leaks.
Then they'll install a suitable filtration system to ensure that the water collected is clean and safe for use. Then a pump and distribution system will be set up to ensure that the water can be easily accessed and used around your property.
Do the benefits of rainwater tanks make it worth it?
Given all its benefits, yes! Harvesting rainwater with your own tank is easy on the wallet in the long run and great for the environment. It's a significant step towards building a sustainable home and is well worth the investment.
