When selecting a rainwater tank, there are several factors that need to be considered. Obvious considerations are what tank size we need, and what colour we like. Other factors to keep in mind are; what is the intended use of the tank; is the tank for domestic use, for hobby or commercial farming? Space is another important factor; will the tank be placed on a rural property or in an urban area with limited space? These aspects must all be considered, as does the choice of what material we choose for the new rainwater tank.
Water tanks are available in a variety of materials; polyethylene, galvanised steel, stainless steel, Aquaplate®, Zincalume®, Steel Liners, fibreglass, and concrete. Each of these materials have their advantages and disadvantages.
In this article we will focus on poly water tanks. Poly is an abbreviation of polyethylene; in other words, a type of plastic. Plastic is on the top of the environmental agenda and often draws negative connotations for its impact upon the environment. Despite this, poly tanks are the most used tanks in Australia, and for good reasons:
Recyclable: polyethylene tanks are a recyclable and a Multi-use resource. Poly tanks have an engineered design life of 23 years and at the end of this time it is fully recyclable.
Longevity: using the rotational moulding manufacturing technique, poly water tanks have no joints and are made in one piece, which make the tank strong and sturdy in design and build.
Non-corrosive: polyethylene is a material that withstands corrosion, as opposed to metal tanks which tend to corrode over their life cycle. Hence, poly tanks’ service life is longer.
Practicality: poly water tanks are lightweight and transportable, which makes them more manageable and utilitarian.
Sun Protection: poly water tanks often have UV light protection. Bushmans own UV light protection material, Sunsmart®, is a strong barrier between the water tank and the harsh Australian sun. In fact, Bushmans UV light protection exceed the requirement of the Australian standards.
Aesthetic: poly water tanks come in a variety of colours, to enhance the aesthetics of your house or property.
Food Grade: poly tanks are suitable to hold drinking water (potable water).
Plastic – Friend or Foe?
The discourse in the media and the general discussion around plastic is that it is inherently bad. We are presented with images of plastic in our waterways, in our community or told of its negative effects on wildlife.
These images and stories are true to an extent but not the fault of the material. The problem is single use plastics and plastics entering the environment. If plastics are recycled, then the problem goes away. The other issue bought up is microplastics. Primary microplastic are tiny particles of plastic (less than 5 millimetres in size), originating from an array of sources, some as commonplace as cigarette filters, textile fibres and even cleaning and personal care products.
Microplastic can also be formed by larger plastic items which have been broken down by sun, wind and the ocean – secondary microplastic. Again, recycling and reusing addresses this issue.
We can all agree that plastic does not belong in our waterways nor in any other area in our natural environment. But is there such thing as good plastic? As a start, a reasonable question to ask is if the result of plastic in the ocean, on the side of the streets or in other areas in our community is the fault of the material, plastic? The reasonable answer is – of course not! The plastic ends up in the wrong place because the product has not been disposed of correctly. Well, actually, disposed is the incorrect term here, because plastic items should be recycled.
One of the main characteristics of polyethylene tanks is their longevity. When reaching the end of its long life as a vessel for rainwater harvesting and water management, the poly water tank has served its intended purpose. However, the poly material goes beyond its use as a water tank and it can have several lives when its recycled. The poly can be manufactured into another product and serve for many years to come.
Our Responsibility – Closing the Loop
Bushman Tanks and the Rotomoulding Association of Australia is taking the environmental impact that plastic can have very seriously. It is now recognised that the tank selection process should include another important step; a plan for how the water tank is recycled at the end of its product life. This is how the loop is closed, plastic can continue to serve, and the environment is looked after.
Contact Bushmans: 1800 888 000
You will find more information on how to select a water tank here.
Do you want to estimate your domestic water use? Click here for Bushmans Water Usage Calculator.
Bushmans: Tank Material Comparison
This is plastics: Plastics 101
Photo by Merakist