Water Tank Dimensions

Pioneer Water Tanks - Water Tank Sizes and Capacity

A Range of Water Tank Sizes

For more than thirty years now, Pioneer Water Tanks have been helping families in areas across WA in need of large water tanks meet their rainwater harvesting needs, with dimensions and capacities up to 500,000L. Pioneer Water Tanks is an Australian owned company that continues to lead the industry with Aussie innovation and local knowledge.

As well as making round water tanks in a wide range of water tank sizes, Pioneer has ensured that the water tanks we build last well into the future, with a host of testimonials to the quality of our tanks highlighted by the fact that most of the tanks built back in our first year of business back in 1988 still operate to this day.

With a range of capacities available; the dimensions are also important to understand, as two tanks that are the same size in terms of storage capacity may be very different sizes when it comes to diameter, height and footprint.

Pioneer Water Tanks wants to make your water storage purchase as easy as possible, from the quote stage and throughout your tank’s service life, so have put together a guide for all you need to know about water tank dimensions.


Pioneer Water Tanks have provided a service for Western Australia since 1988. Our high quality Australian-made water tanks will provide the long-term water security you’re looking for.

Water Tanks Dimensions

What size water tank do I need?

The water tank size that will be best for your home or farm will be determined by both external and internal factors, which include your annual rainfall, the size of your roof or roofs that you are harvesting rainwater from, and the amount of water you use annually.

Your total annual rain harvesting ability can be determined by multiplying your roof size in square meters by your average annual rainfall in mm (microclimate of your property if possible, as it may be different to local rainfall figures), which would look something like the equation below:

Roof Size ( ) x Annual Rainfall (mm) = Rainwater Harvesting Ability

300  x 850mm = 255 000L

For the average household sizes, Pioneer Water Tanks typically recommends the following size water tanks:

  • 2 Persons: 90 000 litres
  • 3 Persons: 110 000 litres
  • 4 Persons: 150 000 litres
  • 6 Persons: 250 000 litres

However, it is important to remember these figures are simply recommendations, and should not be seen as exact. Some households have higher or lower demands than others, and some have larger dimensions when it comes to roof space, and may choose to harvest additional rain in order to water gardens, lawns or animals. 

Bushfire e-book

Bushfire Protection with Pioneer Water Tanks

Pioneer Water Tanks also come with the option of an additional fire reserve of up to 20 000 litres, so if you are looking to use your rainwater tank for fire protection, you may want to keep in mind the extra storage when purchasing your water tank – particularly if you have the extra space and rainwater harvesting ability available.

Water Tank Size Chart

pioneer water tank sizes and dimensions

The Litre/Gallon stated above are gross capacities. Actual useable volume will vary depending on the size and position of inlets and outlets.

Other dimensions of a water tank to consider

When your water tank is installed, there needs to be a clearance of 1m on each side of the tank, in order to prevent any issues when installing, or future access issues for maintenance throughout your water tank’s service life.

This means the width of your tank pad will be 2m wider in total than the diameter of your tank (e.g. a GT110 will require a sand pad that measures 10.02m in diameter).

Any rainwater tanks should also be located 50 mm (5 cm) below the gutter for every 1000 mm (1 meter) away they are located, in order to ensure effective delivery of your harvested rainwater to your rainwater tanks.

For further information on your sand pad location, and heights of any gutters or pipes, your local Pioneer Dealer will be able to answer your question in regards to all applications.

Other water storage tank options

Looking for small water tanks?

While Pioneer Water Tanks are Australia’s #1 big tank company, there are many people who don’t want or simply don’t require such a large water tank.

For these people there are a range of poly water tanks and corrugated water tanks available in a range of styles such as; slimline tanks, round tanks and rain barrels.

These tanks are more for people who have access to mains water, but are looking for a smaller size tank to sue for drinking water or to help them get more value out of their garden.

If you’re not sure if a Pioneer tank or a small water tank will be best for you, get in touch with Pioneer Water Tanks today to discuss the features and benefits of each option.

two poly water tanks on a rural property in front of a dramatic sunset

Water Tank Fittings and Accessories

In addition to our range of standard water tank fittings accessories – which include our industry leading  Aqualiner Fresh® antimicrobial water tank liner – Pioneer Water Tanks offers a range of optional water tank accessories, products which have uses that make your water storage easier or more personalised.

Standard Rainwater Tank Accessories

aqualiner fresh layers example antimicrobial water tank liner

1 x Exclusive Aqualiner Fresh® Water Tank Liner

a 50mm outlet with ball valve fire fitting for steel water tanks

1 x 50mm Outlet & Ball Valve

a pioneer water tanks stainless steel leaf filter basket for steel water tanks

1 x  Stainless Steel Leaf Filter Basket or 50mm Inlet

a galvanised steel ladder for large steel water tanks hook on ladder with bracket

1 x Hook-On Galvanised Ladder with Bracket

pioneer water tanks hinged galvanised steel roof access hatch water tank access hatch

1 x Heavy Duty Hinged Access Hatch

a pioneer water tanks 150mm overflow 150mm bellmouth

1 x 150mm Overflow, Downpipe and Flap Valve

a single annode bag sacrificial anode for steel water tank corrosion protection

1 x Set (2) of Anodes

Optional Rainwater Tank Accessories

ball valve outlet for steel water tanks

Fire protection valve and fire water reserve to shire standards

an analogue water level indicator with float valve and weight

Digital or traditional water level indicators

four pioneer water tanks smart water savers tank roof gutter system pieces

Gutterless tank roof rainwater harvesting system

a close up photo of water tank liner protection water tank underlay fabric geotextile underlay

Geotextile underlay to protect liner from damage

SuperSeal water tank dustproofing and vermin protection for water tank freshness

SuperSeal dustproofing condensation strip pack

(standard across Queensland and a recommended product for potable water storage)

20/20 Water Tank Warranty

Another important feature that comes with your water tank is Pioneer’s 20/20 Warranty;  a 20 year conditional structural warranty in addition to a 20 year conditional warranty against water leakage, applicable on all rainwater tank models from GT10 – GT280.

Pioneer understands that for our customers are an investment, and something you likely only want to buy once in your lifetime, and most of the water tanks built by Pioneer Water Tanks all the way back in 1988 still remain in service to this day, holding water as securely as they did the day they were built – a testament to their design and ability to withstand the pressure of the brutal Australian climate, and the pride of the Pioneer brand name.

Pioneer Water Tank Colours

Another type of accessory that doesn’t necessarily improve the performance of your water tank – unless you are near the coast – but will likely improve your appreciation of your water tank is our range of Colorbond® steel water tank colours.

Pioneer Water Tanks offers the full range of BlueScope’s Colorbond® colours, with eight standard colours available and the rest available on request.

Standard Colorbond® Water Tank Colour Range



Classic Cream™

Woodland Grey®




Pale Eucalypt®

Non-Standard Colorbond® Water Tank Colour Range

Dover White™

Evening Haze®



Shale Grey™





Night Sky®


Deep Ocean­®

Cottage Green®

Manor Red®

Standard Colorbond® Colours

Non-Standard Colorbond® Colours

A range of rainwater tank dimensions to meet your needs

If you have more questions in regards to the sizes and dimensions of Pioneer Water Tanks, or what water tank would be best for your needs get in touch with us on 1800 999 599, or by simply clicking here to leave your details and request a quote for a water tank today; and one of our dealers will be in touch.

Frequently Asked Questions

What is the standard size of water tank?

The advantages of water tanks is that there really are no standard water tank dimensions, which allows you to personalise the size tank you purchase to be the right water tank size to suit your needs. Most Pioneer Water Tanks installed each year are between 100,000L and 200,000L, however this includes multiple options for water tank sizes and dimensions.

What are the dimensions of a 100,000 litre water tank?

Pioneer’s GT110 water tank, which offers a gross capacity of 110,116L of water storage is 2.18m in height and 8.02m in width, and requires a sand pad of 10.02m. The roof has a rainwater harvesting area of 50m² if you choose to install Pioneer’s Smart Water Savers.

Who decides the dimensions of the water tank?

While the basic dimensions of Pioneer Water Tanks are decided upon by our engineers, the dimensions you end up with is entirly up to you, as you have the choice of Pioneer’s range of water tank sizes from 12,000L up to 500,000L.

What are the available sizes of water tanks?

Pioneer Water Tanks have a wide range of water tank sizes available, starting at 12,000L and going all the way up to 500,000L. There are 22 options for water tank sizes and dimensions to allow you to get the perfect water tank dimensions for your property.

What is the maximum capacity of a tank you offer?

Pioneer Water Tanks largest water tank is the GT500 which offers 500,000L of gross water storage. For most people this is far more than they would need – or even be able to harvest.