Orange, New South Wales - Water Resources

Water Resources

Orange has several water sources used for domestic consumption, both currently in use and formerly used. Currently Suma Park Dam and Spring Creek Reservoir are used for domestic water consumption. Two other dams, Lake Canobolas and Gosling Creek Reservoir, were previously used for domestic water consumption however are now used for recreational purposes. Orange was on Level 5 Water restrictions, however after heavy rain increased capacity from around 20% to 100% restrictions were eased back to level 2. Orange City Council is undertaking a number of strategies to supplement its supply, including stormwater harvesting.

The first batch of harvested stormwater was released into Suma Park Dam on 21 April 2009. The harvested stormwater was tested by Analytical Laboratory Services, an independent laboratory based in Sydney. ALS tested for 90 potential pollutants. The tests revealed that the water quality met all targets. The first batch contained 14 megalitres. It is believed to be an Australian first for harvesting stormwater for potable use. The hardware is in place, operating rules have been developed and environmental factors and impacts on downstream users have been considered. A three month trial will ensure all these elements are working together to ensure high water quality and environmental standards are met. There are several phases involved in the commissioning period. The hardware, which includes three separate pumping stations, creek flow monitoring points and advanced electronics including fibre optic cables, will undergo further operating tests. The other elements of the scheme include a weir on Blackmans Swamp Creek, which creates a 3 megalitre pool and the site for the first pump station, a 200 megalitre dam and two 17 megalitre batching ponds.The pumps on the creek transfer stormwater to the 200 megalitre dam at a rate of up to 450 litres per second and are designed to rapidly extract peak storm flows from the creek. The operating rules require that a base flow immediately downstream in the creek must be maintained. The creek flow monitoring points ensure these standards are met. The monitoring station also measures when harvesting can commence. The trigger is flows passing the monitor in Blackmans Swamp Creek exceeding 1000 litres per second.

The local mine, Cadia-Ridgeway Mine, uses the city's treated effluent to supplement its water supply.