Water management
Royal Botanic Gardens Melbourne plays a leading role in effective water management of garden landscapes, beginning with the installation of an automatic sprinkler system in 1994. The Gardens are constantly striving to improve irrigation efficiency, stormwater treatment, lake ecosystems and water quality in the lake system.
The RBG Melbourne has developed water management strategies to help reduce the amount of water we use and to develop sustainable garden management practices in a drying climate. Amongst these strategies is a high focus on active research on landscape water use to improve water use efficiency whilst maintaining plant health.
Catch-can testing of the irrigation system on Central Lawn. This test measures the precipitation rate and how uniformly the water is applied. It helps identify any improvements that may be needed to improve efficiency of the system.
Effective water management first became a concern at RBG Melbourne in 1994, when a new automatic irrigation system was installed and more efficient methods of water usage were adopted.
Water is managed in as a ‘whole of catchment’ concern. RBG Melbourne is committed to researching issues such as irrigation efficiency, stormwater treatment, lake ecosystems and water quality, and the effectiveness of rainfall within the landscape.
It is sometimes hard to comprehend the volumes of water involved in large gardens. Many people would think 10mm of rain is a minimum to provide enough water for a residential garden. One mm of rain over one square metre equals one litre . Over a residential garden of 1000 square metres, 10mm of rain equals a volume of 10,000 litres. Over a landscape the size of RBG Melbourne (38.6 Hectares), 10mm of rain equals 3,860,000 litres, 3,860 kilolitres, or 3,860 tonnes of water!
Climate change predictions presently indicate that Melbourne will continue to have lower than average rainfall and increased temperatures into the future. This places a particular emphasis on improving water use efficiency and finding more sustainable sources of water for the Gardens.
In order to meet our responsibilities as set out in the Royal Botanic Gardens Act 1991, it is essential that we protect and maintain our gardens, facilities and programs under any future water supply scenarios. Thus, it is imperative that we secure future water supplies that will fulfill our needs, recognising that we still need to use water as efficiently and effectively as possible.
In 2007, the Strategic Water Plan was adopted for integrated water management at both RBG Cranbourne and RBG Melbourne. The plan provides strategies and actions to move the Royal Botanic Gardens forward in seeking more sustainable use of water resources under a drying climate.
The ‘Working Wetlands’ project is one of the outcomes of the Strategic Water Plan. This development is currently being built and is intended to capture stormwater from adjacent streetscapes and treat it through wetlands and water recirculation to improve the aquatic ecosystem in the Ornamental Lake. Ultimately, it is anticipated that enough water will be harvested to improve the health of the lake system with up to 40% being available on an annual basis for irrigation.
Last updated 27 Apr 2011
