Collection of rainwater is an ancient practice that dates back over thousands of years. It is a relatively common practice in rural and remote areas, with Australians using it as a source of water for gardening, bathing, showering, and even drinking.
The collection of rainwater and the use of rainwater tanks have become a strategy to improve water conservation and address significant impacts of droughts and climate change. Water tanks now offer different uses, such as laundry, drinking water, garden water, ventilation for buildings and protecting homes from bushfires.
Compromised Water Quality
Along with versatility in the use of water comes a corresponding risk — a microbiological hazard. The quality of rainwater is not as reliable as mains water, especially after rain events that follow dry spells. Rhino Water Tanks notes that while the risk of contracting illness is low, it is still important to address the threats that can compromise water quality.
Microorganisms in the Water
Water stored and collected in rainwater tanks will contain microorganisms from one or multiple sources. Although most are harmless, the safety of water is highly dependent on minimising the presence of enteric pathogens, which include viruses, bacteria and protozoa.
This is why rainwater tanks are elevated, and collect water from roofs via guttering. Common sources of enteric pathogens include faecal material from birds, mice, rats, lizards and other animals. These may also include insect and dead animals in the tank or gutters.
Sensible management procedures can help minimise the hazards for rainwater collected in tanks. Design and installation also matters, as well as regular maintenance. Simple systems such as piping, guttering, and roof catchments are simple systems that can preserve quality. System analysis is also beneficial to identify and assess the hazards that can affect rainwater quality.
It is possible to minimise contamination of harmful microorganisms by keeping roof catchments clear of branches, as they provide roosting points for birds as well as access for small animals. It is also important to secure roofs and seal sides to prevent ingress. Swimming in the storage tanks is never advisable, as this type of access greatly increases risks of contamination.
The use of quality tanks, along with six-monthly inspections, is necessary. Tank owners should also make it a point to inspect it every two to three years for the presence of sediments. Rainwater used for commercial purpose will also require testing to confirm suitability.