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Shapes, Sizes, and Dimensions of Various Rainwater Storage Tanks

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After moving on to a large property without town water Peter had to learn quickly the best way to harvest rainwater and control grey water.

Water storage tanks, just about any shape, color or size you could imagine!

Water storage tanks, just about any shape, color or size you could imagine!

Rainwater Storage Tank Sizes

Rainwater storage tanks do come in all shapes and sizes, and just about any colour that you could choose. This article is designed to give you the information needed to help you decide if you want to get a water storage tank.

My household survives on water harvested from the rainfall, and we wouldn't want it any other way. If we ever move from our 2-acre property, we will definitely be installing some form of rainwater capture and storage system at our new place, since we've found ours so beneficial.

Water Tank Sizes and Shapes

From the observations I have made through my years of research, there is such a large number of different types of tanks available, I could not possibly cover them all in this one article. They are made from many different materials.

If anyone has come across any other type or shape, let me know and I will include it here for everyone's benefit!

I have sorted through all of my research and short-listed the most popular for your perusal!

A nice little corrugated steel tank fitted into the garden environment.

A nice little corrugated steel tank fitted into the garden environment.

Corrugated Galvanized Steel

Corrugated Galvanized Steel. These tanks are hand riveted and sealed with compound (in Australia, the old method of soldering has been banned) and if required for potable water, they are internally coated with approved certified coatings. Linings are also available to fit inside the tank. It is recommended that they be installed on a concrete pad.

Although very popular in the past, these corrugated galvanized tanks are being outsold by the plastic (polyethylene) tanks. This could be due to lower costs, the fact that the poly tanks look nicer and can be manufactured in just about any form and colored to fit into the surrounding environment.

Slimline poly tank used as fence or wall!

Slimline poly tank used as fence or wall!

Plastic (Polyethylene) Rainwater Tanks

Due to the manufacturing process, plastic (polyethylene) water-storage tanks can come in just about any shape or form you can imagine: round, slimline (becoming popular due to houses being built on smaller blocks) and rectangular. Research shows that the size of these tanks can vary between 700 and 5,000 litres. I believe that they are now even bigger.

These polywater storage tanks can also be purchased in a variety of colors; including, greens, reds, browns, beiges and many more.

Concrete water storage tank decorated to blend into the environment.

Concrete water storage tank decorated to blend into the environment.

Water-Storage Tanks: Concrete

Concrete water storage tanks are very popular in Australia and are manufactured to strict regulations with bases up to 4 inches thick, walls up to 2 inches thick and roofs up to 4 inches thick.

All concrete is reinforced with either galvanized welded mesh, wire and/or rods. The larger models have a center support column.

Capacities can vary from 1000 gallons (5000 litres) to 5500 gallons (25,000 litres). On my property, we have 3 concrete tanks capable of holding 15,000 gals (67,000 litres) of water. We have had overflow only on 2 occasions!

You can never have enough water, so we have now installed a 3000-litre rectangular tank under our deck. It is fitted with a pressure-operated electric pump and is used for the garden!

A bladder storage tank fitted and plumbed in the under house cavity.

A bladder storage tank fitted and plumbed in the under house cavity.

Bladder Water-Storage Tanks

Bladder water-storage tanks are now popular due to lack of space in the modern home and a requirement of some building authorities that water storage be mandatory in new homes.

Bladder storage tanks can be installed under houses, decks, etc., and can be removed when the owner decides to relocate.

Potable water bladder tanks are made out of material approved for storing consumable liquids and come in sizes up to about 10,000 gallons. The job of fitting bladder tanks under a house can be quite formidable and it is recommended to have them specially fitted.

Dimensions and Capacities of Various Water Tanks

To give you some idea on the size of the tank for the required amount of water, I have listed below the dimensions and approximate capacity for some popular tank sizes, I hope this information is useful, though this is by no means a definitive table!

Capacity of Water Tanks

Capacity of tanks as an example for the purpose of this exercise I have taken the liberty of rounding off numbers and using a conversion factor of 1 Gallon = 4.5 litres and 1 cubic foot = 7.5 gallons.


3 feet (0.9mtr)

6 feet (1.80mtr)

220 gals (1,000ltr)

7.8 feet (2.40mtr)

6 feet (1.80mtr)

1770 gals (8,000ltr)

Underground tanks resemble donuts and bagels.

Underground tanks resemble donuts and bagels.

Water-Storage Tanks Underground

These days some home builders have decided that the above-ground storage tanks are not to their liking, and more people are opting to have their water storage tanks installed underground- similar to how a petrol station has its fuel tanks underground!

These tanks can be any shape, but most are designed using a round shape because, I believe, it is a stronger structure and can withstand many years of pressure from the surrounding fill.

Underground water-storage tanks have quaint names such as "donut" and "bagel" for obvious reasons.

This article is accurate and true to the best of the author’s knowledge. Content is for informational or entertainment purposes only and does not substitute for personal counsel or professional advice in business, financial, legal, or technical matters.

© 2010 Peter


Peter (author) from Australia on August 23, 2019:

Jorja , to find out the dimensions of each tank you will have to contact the individual manufacturer. Tanks can be all shapes such as round, oval, cube etc.. They can even be made to order to your own dimensions! I hope this answers your question.

Jorja on August 11, 2019:

Could please send the dimensions for 1200 litre tanks in a cylinder and a rectangle, high and skinny and cube, thank you so much.

A raja on May 04, 2018:

kindly send me the dimensions for 5 ltr tank

Charles Gbekle on September 02, 2017:

Kindly send me the dimensions of a 1200 liters water tank of 1200 mm diameter of a dome shape.


Peter (author) from Australia on January 06, 2011:

whitton I hope the information on water storage shapes and sizes is helpful.

Thanks for dropping by and leaving a kind comment :-)

whitton on January 06, 2011:

Thanks for sharing. This is great information.

storage tank manufacturers india on December 08, 2010:

This product is manufactured using quality raw material, thereby making them sturdy and durable. Being very easy to install and high functionality, our products find extensive usage in host of industries like chemical, petrochemical, agrochemical, thermal, cement,and cosmetics. Leveraging on our flawless product range, we have carved a niche for ourselves in the market

Peter (author) from Australia on July 17, 2010:

Yes there is such competition our there now with the manufacturers, especially here in Australia, you can go to them and get custom made just about any shape, size and color Water storage tank that you may desire!

World-Traveler from USA on July 16, 2010:

I had no idea that there was such an incredible variety of water storage tanks. Thanks for that information.

Peter (author) from Australia on March 13, 2010:

Dale Mazurek , thanks for dropping in and leaving a great comment.

I am honored that you would put one of my Hubs on your Blog.

It's a great idea you have going there and I would advise anyone to go over and have a look. It would be great to see more promotion of Hubbers away from HubPages and to date yours is one of the best I have seen.

Dale , thanks again :-)

Dale Mazurek from Canada on March 13, 2010:

What an interesting hub.

How people can learn here at Hubpages.

I am glad to have been able to place this hub on my blog.

The link to my blog can be found at the bottom of my profile page



Peter (author) from Australia on March 01, 2010:

earnestshub, thanks for the kind comment. I also would opt for concrete tanks in a high bushfire risk area. I believe that during our last bad fires quite a few people saved their own lives by jumping into a full concrete water storage tank.

Peter (author) from Australia on March 01, 2010:

Springboard, thanks for droppin by. Even though it may not be practical we can all practice water saving methods.

It really annoys me to see all of that water gushing down the drain after a rain storm, you would think there would be some way of saving the millions of gallons being wasted!

earnestshub from Melbourne Australia on March 01, 2010:

A timely and useful hub as usual agvulpes. I hope more people consider the advantages of these modern storage systems. If I were in a high bushfire risk area I would opt for the concrete one I think.

Springboard from Wisconsin on March 01, 2010:

It's a bit less practical an idea for me since I live in the city. But I think it's a wonderful idea, and I actually think many cities could benefit by capturing more of the stuff to be processed. Never hurts, IMO, to have a conservation effort of any sort.

Candie V from Whereever there's wolves!! And Bikers!! Cummon Flash, We need an adventure! on February 27, 2010:

If Christoph is going to put in a swimming sized one.. I'm going to his house! I'll bring the margaritas Christoph!!

Peter (author) from Australia on February 27, 2010:

prasetio30 thanks for dropping by. This whole field is ever exanding and as our water supplies dwindle and people see opportunity to make money the field will grow even more :-)

prasetio30 from malang-indonesia on February 27, 2010:

Thanks for share. This is wonderful information. I never know about kind of these tank before. good work.

Peter (author) from Australia on February 26, 2010:

Oliversmum, thanks for your great comment. I do agree with you about the bladder tanks! They are becoming very popular as they become cheaper to buy.

It is not that hard to set up some sort of tank to gather water even if it is only used to water the garden.

Oliversmum, thanks again for your kind comment :-)


Peter (author) from Australia on February 26, 2010:

Darlene, thanks for you input. I don't know what other countries are like but in my town of Melbourne you could pop your head over the back fence of any decent gardener and see a tank of some description. From plastic wheelie bins to cut off 44 gallon drums.

Darlene Sabella from Hello, my name is Toast and Jam, I live in the forest with my dog named Sam ... on February 26, 2010:

Excellent hub, I love the idea of these tanks, not only for emergercies but for outside watering and it's purest form. Thank you

Peter (author) from Australia on February 26, 2010:

hypnodude, thanks very much for the thumbs up, in Victoria especially our water supply seems to be going backwards and the cost of water is due to sky rocket. So every little helps.

Thanks for dropping in :-)

Peter (author) from Australia on February 26, 2010:

Christoph, you raise a very good point. You may have only been joking but during the terrible bush fires last year where there were so many people killed, a number of lives were saved by people jumping into the large water tanks. I believe they were the concrete structured water tanks.

Mate, Thanks for dropping by it's always a pleasure to see you :-)

Andrew from Italy on February 26, 2010:

Very interesting agvulpes. These are the kind of informations which can be pretty useful. And the layout is great. Thumbs up.

oliversmum from australia on February 26, 2010:

Agvulpes.Hi.What a fantastic hub, with all this fantastic information and the great variety of Water tanks available, every home should have one. I love the Bladder storage tank for under the house,It's great, I am also glad you published this information to let folks know how easy it is to collect their own water.Thank you. :) :) (hug)

Peter (author) from Australia on February 26, 2010:

Candie V , me dig holes, noooooo way! These days I break out in a sweat just cleaning my nails :-)

Thankyou for your kind comment.

Christoph Reilly from St. Louis on February 25, 2010:

Can you build one you can go swimming in?

Candie V from Whereever there's wolves!! And Bikers!! Cummon Flash, We need an adventure! on February 25, 2010:

Excellent continuation on your water storage tank series! If I put one in, can you come help me dig the hole? Thank you!!