Frequently asked questions

Rainwater Harvesting & Stormwater Management

What is rainwater harvesting?

Rainwater harvesting (also called roofwater harvesting) involves the collection, storage and distribution of rainwater from the roof, for use inside and outside the home or business.

How can rainwater be used?

In some rural communities rainwater is the only supply of water for human consumption. Rainwater can be used as a source of water for all requirements - drinking, cooking, bathing, laundry, toilet flushing through to watering the garden. Nowadays, even when mains or reticulated water supplies are available to communities, many people choose to use rainwater that is collected from the roof and stored in tanks or other vessels to supply their water requirements. Rainwater is an ideal source for our water requirements and momentum behind rain harvesting is building.

How much water can be collected from snowfall?

On average, thirteen inches of snow equals one inch of rain, although this ratio can vary from two inches for sleet to nearly 30-40 inches for dry, powdery snow under certain conditions.

What are the benefits of using rainwater ?

Significant economic, social and environmental benefits can be achieved by using rainwater. By using Rainwater Harvesting systems to supply water for some, or indeed all of our requirements, you can reduce your dependence on mains water. Our water supplies are falling and water restrictions are in place in many communities to reduce our overall water usage and protect our supplies. There is no better quality water available naturally than rainwater. Some say there are health benefits to using rainwater which is not treated with chemicals like our mains water is. Rainwater falls for free - once you have installed a rain harvesting system, you use less mains water and can reduce your water bills. Governments and Water Boards will increase water prices as they look to recover the true costs of providing water to the community. The cost to the community to supply mains or reticulated water services is becoming more expensive every year. The construction of dams, pipes and treatment plants is huge and ultimately as tax and rate-payers, we foot this cost. Rainwater Harvesting reduces the significant damage to our creeks, water habitats and organisms caused by stormwater runoff. Rainwater that is captured and stored correctly is a safe, economical and sustainable source of quality water. Safety measures can be applied to the manner in which rainwater is captured, stored and dispensed. In fact some people argue that rainwater is safer than water supplied through mains or reticulated water systems. Our mains water is typically stored in dams, treated with chemicals such as chlorine to kill of bacteria and make it safe, and then pumped through a network of pipes throughout the community. It makes sense to catch the rain that falls for free without chemicals.

What size of tank do I need?

Things you need to consider when determining the size of your tank or storage vessel include: Rainfall: how much rainfall you get in your area. Roof area: how large the catchment surface is. Water usage: what you intend to use rainwater for, and how much you expect to use. Site characteristics: how much space you have, and the location you intend to install the tank or storage vessel. CALCULATING THE APPROPRIATE SIZE Use the following formula: Roof Area X Annual Rainfall = Maximum Available for Capture, then determine: Most Days without Rain X Average Daily Water Use = Storage Volume Required on Day One of a Dry Spell If for example, the most days without rain was 40 days, and the average daily usage was 400L, the volume on hand on Day One of 40 days would have to be 16,000L. It is very difficult to predict the required volume, because often a dry period will start when the tank is not full. However, this method provides a guideline, and you can add a safety factor on top of this requirement. When calculating how big the storage capacity should be, plan the tank area so that extra storage can be added later if required.

How should I place my tank?

It is important to consider the space you have available, whether the vessel is to be installed above or below ground, below the roof-line or above it (eg. on a sloping site), whether you will have one or more tanks - connected or installed as separate systems, and what ground surface preparation is required.

What is a first flush water diverter?

Our First Flush Water Diverter Kit is a device that prevents most of the debris on the collection surface: leaves, twigs, dust, bird droppings etc. from entering the tank. This device is highly recommended if you plan to use your stored rainwater in an irrigation

Can you hook two or more of your tanks together to get a larger capacity for holding more rainwater? Can you mix the sizes?

Yes, a BARR Rainwater Collection specialist will be able to provide you with the necessary piping & fittings to connect multiple tanks. Sizes can be mixed but please contact us for more information on ideal size mixes.

Do I need a plumber to install my tank system or can I do it myself?

Our rainwater collection systems are do-it-yourself friendly. Products come with the necessary instructions to install any of our products. A BARR Rainwater Specialist can provide you with assistance over the phone or in our warehouse to help make your tank installation as easy as possible.