Investing in a water tank is wise, as it saves you money and reduces reliance on water supply companies. Underground water tanks are a preferred choice for many homeowners because they don’t interrupt your outdoor design and leave enough room for other backyard structures.
Here are the most common types of underground water tanks.
Aluminium or Steel Tanks
Most underground tanks in Australia are made using aluminium or steel. The tanks come in many shapes: square, rectangular and cylindrical. You can install the tank vertically or horizontally. Aluminium and steel tanks require many accessories, including hold-down lugs, ladders, saddles, dispensing valves, and internal baffle plates.
Steel and aluminium are durable, but you make the tanks last longer by adding primer, paint, and special coatings. These tanks have a capacity of up to 100,000 litres.
On the downside, steel and aluminium are expensive. In addition, the toughness of the materials means you need to dig deeper, more expensive installation holes.
Composite Over Wrapped
Composite over-wrapped tanks consist of a blend of two more materials with different chemical and physical properties. It’s this difference that makes the tanks suitable for underground installation.
Materials used to make composite over-wrapped tanks include carbon fibre, glass fibre, and other plastics. After blending the compounds, the outer surface gets a metallic protective shield to increase durability and prevent corrosion.
Another typical composite design involves mixing metals with organic compounds or ceramic. When combined with ceramic, metal produces cermet. This is a material renowned for its robustness and durability.
Pillow tanks are ideal for homeowners who like versatile underground storage tanks. They have huge storage capacities and are portable.
The name ‘pillow’ refers to these tanks’ shapes, like the pillow on your bed. As mentioned earlier, pillow tanks are versatile and can store potable or sewage water. Moreover, they’re more affordable than other types and easy to install and customise.
Regardless of your storage needs, a pillow tank will work for you. These tanks can store between 5,000 and 100,000 litres.
Like pillow tanks, fibreglass is popular because of its versatility. Furthermore, the material is corrosion-resistant and relatively cheap, making it a suitable choice for commercial use.
The most significant disadvantage of fibreglass tanks is they have a predefined shape. This leaves a little room for flexibility, as you must dig deep into the ground to accommodate the structure.
Thermoplastics are composite materials used to make underground storage tanks. The manufacturing process combines carbon fibre with polymer liner to make savvy tanks that can store various fluids, such as petroleum products and water. In addition, these tanks are resistant to erosion and can last at least 15 years.
Concrete tanks are undoubtedly the most flexible underground storage solutions. You can design a tank to conform to the space in your backyard. Some points can be deep, others shallow, etc. Similarly, you can choose a defined shape or something that matches the surroundings.
Additionally, concrete tanks are durable. If you choose the right materials and installers, they can last for a lifetime.
The problems with concrete tanks are expensiveness and taking long periods to complete. You have to wait for months before the tanks become usable.
As seen above, you have many options to choose from when installing an underground storage tank. Most come readymade, meaning you have to excavate a hole that fits. However, some, like the pillow and concrete tanks, offer a little flexibility.
Ultimately, your preferences and budget determine the tank you install. That said, concrete tanks are the best because they guarantee durability and offer flexibility.