In 2014, researchers from the University of Western Sydney studied the reliability and cost-benefit ratio of rainwater harvesting systems for peri-urban regions in Greater Sydney. They found that rainwater collection can supply up to 99% of toilet and laundry needs during the wet season and 69-90% during the dry season.

1. Rainwater Harvesting in
Australia Can Sustain Up
To 99% of Freshwater
Needs in Households
Durotank

2. Rainwater Tanks as Primary Water Sources
Australia is the world’s most arid inhabited continent. The limited water supply has compelled the
government to impose water use restrictions in several cities as early as 1977 in Perth, Western
Australia. They are necessary because many areas of the country rely on rainfall as one of its major
water sources.
This prompted Ken Mathews, then-chief of the National Water Commission, to call for concerted efforts
to diversify Australia’s water supply source and reduce the country’s reliance on climate and rainfall.
In 2014, researchers from the University of Western Sydney studied the reliability and cost-benefit ratio
of rainwater harvesting systems for peri-urban regions in Greater Sydney. They found that rainwater
collection can supply up to 99% of toilet and laundry needs during the wet season and 69-90% during
the dry season.
These percentages go down with extra use. Researchers found that rainwater collection can supply 63-
96% of combined irrigation, toilet and laundry needs, depending on the location and rainfall volume.

3. Although there have been months when local governments lift water restrictions depending on available
water supply, for the average household, continuing to collect water during the rainy season affords
them water supply security.
Optimal Tank Size and Type
The research from the University of Western Sydney recommended the use of a 5,000L tank for
rainwater collection, as its data shows that it produces the best cost-benefit ratio.
Preserving the integrity of rainwater runoff is also important. According to a study from the University
of Texas, rainwater runoff collected from metal and concrete tile roofs have the best quality for
household use.
For storage, tanks specifically made for rainwater collection are optimal, although never-before-used
diesel fuel tanks are also acceptable. According to the Alabama A&M and Auburn Universities, lined fuel
tanks are good for collecting rainwater for irrigation.

4. Rainwater collection is economical, sustainable and environmentally friendly. Locals stand to benefit
more, however, by diversifying their water sources. They will enjoy long-term benefits and have better
water security.
Sources:
http://researchdirect.westernsydney.edu.au/islandora/object/uws:23007
https://www.rainwaterharvesting.org.au/
http://www.abc.net.au/am/content/2007/s1926458.htm
https://www.ncbi.nlm.nih.gov/pubmed/21232781
http://www.smh.com.au/environment/weather/record-dry-spell-sends-sydneys-water-use-soaring-
20170924-gynz16.html
http://www.durotank.com.au/product/poly-water-trailers/