C1.3 Rainwater, stormwater and recycled water for landscaping
Large quantities of water are used around houses for landscaping and food gardens. This can account for up to half of the water used by a community. There are examples throughout this guide of how the use of yard areas and outside areas around the house support the nine Healthy Living Practices. However, as water shortages increase, it can be hard to justify using potable water for gardens and landscaping. Rainwater, stormwater and recycled water are under-utilised water sources that could be used as part of a total water management strategy.
Regardless of the water used for external use, it is strongly recommended that native plants and other drought tolerant species be used to reduce water consumption and encourage water conservation in the community.
Rainwater can be collected directly from roofs and stored in tanks on houses and community buildings and can be a good source of drinking water in communities where the water quality is poor, see B4.1 ‘Quality of drinking water’. Rainwater can be also used for gardens and outside areas to supplement the water supply in communities where potable water is readily available. It will usually be cheaper to install and maintain rainwater tanks than to expand the capacity of the community water supply system. Planning considerations include how much tank capacity can be afforded and how many tanks can be accommodated on the site.
Rainwater can also be ‘harvested’ from roads and open areas around the community, instead of being wasted by washing away in drains. This water is often called ‘stormwater’; it is not suitable for drinking as it picks up pollutants from the ground, but it is a useful resource for landscaping. Stormwater can be collected at ground level in small dams or directed via drains and swales to gardens and landscaped areas. It can also be collected from roads and other hard surfaces into underground tanks, however this is a less cost effective way of storing stormwater.
Recycled water is water that has been used once in a house and is then treated so the any solids and contaminants are removed and it can be used again. Water has been recycled for many years in many overseas countries, and in some places the water is treated to drinking quality. The use of recycled water is limited in Australia, but it is becoming more common as demand for water increases and water treatment technologies improve.
To date, the use of recycled water in many rural and remote communities has been limited to using the effluent from treatment ponds on woodlots or cattle pasture. However, in communities where water shortages are an issue, using treated wastewater in underground irrigation systems to irrigate trees and landscaping throughout the community may be a viable option. Water from the treatment ponds cannot be used for above ground sprinklers, but there are treatment options that allow use of water in underground irrigation for trees, landscaping and food crops.
At a household level, water can be recycled in the following ways:
- effluent from on-site sewerage systems can be run directly to underground irrigation systems in the yard area
- ground covers and small shrubs can be planted between septic trenches as wind and dust breaks; they will also assist in the function of the septic trenches (do not use plants with invasive root systems)
- after separation treatment to extract fat and oils, water from the laundry, shower and bath can be drained to yard areas in underground irrigation systems (check with state or territory and council regulations)
- the water that is wasted from yard taps, hot water overflow and evaporative air conditioners can be specifically directed to yard planting in gravel drains or underground drains
- water from gutters and downpipes can also be piped to planted areas in the yard or collected in swales to be absorbed slowly by yard planting.
Natural Resource Management Ministerial Council and Environment Protection and Heritage Council. 2006, National Guidelines for Water Recycling: Managing Health and Environmental Risks. National Water Quality Management Strategy: Australian Health Ministers’ Conference
Centre for Appropriate Technology Inc. ‘Operation Desert Stormwater Harvesting’, Bush Tech Brief #3, Our Place, 17, Winter 2002, Alice Springs, http://www.icat.org.au/documents/ op17.pdf
Anda, M & Ryan, J 1998, Saving water for healthy communities: a workbook for Aboriginal communities, Remote Area Developments Group, Murdoch University, Perth.