WATER STORAGE AND USE
There are two catchments supplying water to the ACT; the Cotter River catchment (located wholly within Namadgi National Park in the ACT), and the Googong catchment (located on the Queanbeyan River in NSW).
The Cotter River Catchment has three dams. The Cotter Dam was constructed in 1912, Bendora Dam was completed in 1961, and Corin Dam was completed in 1968. The Googong catchment has only one dam, Googong Dam, which was completed in 1979. The total storage capacity of the four dams combined is 212 GL.
According to ACTEW Corporation Limited (ACTEW), at 16 February 2007 the combined volume of water in these dams was down to 35.17% of capacity which was almost half the volume a year prior. The total water storage in service reservoirs around Canberra was 561.5 ML on 19 February 2007.
Recent water storage
ACTEW announced in May 2007 that they were commencing abstraction of water from the Murrumbidgee River. This was prompted by the continual low inflows to ACT reservoirs.
The Murrumbidgee Pumping Station will have the ability to abstract up to 75 ML per day. The actual volume abstracted will be dependant on the flows in the Murrumbidgee, which must meet requirements determined by the ACT Department of Territory and Municipal Services.
The Cotter Pumping Station pumps water from the Murrumbidgee River to the Stromlo Water Treatment Plant for treatment. The plant at Stromlo meets treatment recommendations of the Australian Drinking Water Guidelines produced by the National Health and Medical Research Council.
The drought and water usage
In December 2006, Stage 3 Water Restrictions were introduced, and may increase further in the future. The proposed July 2007 introduction of Stage 4 restrictions was postponed due to some wet weather in June 2007. Stage 4 restrictions would effectively ban all garden watering as well as imposing other residential, industry and business restrictions. According to ACTEW, these increases are due to record low inflows into Canberra dams, predictions of continued hot and dry weather, and higher than expected water consumption in the ACT.
The recent severe drought conditions which have affected the ACT worsened during 2006, with below average rainfall falling during most months of the year. This resulted in a decrease in water storage levels across the ACT.
Between 2004-05 and 2005-06, the average consumption per person per annum increased by 3.5% to 149 kL. Maximum daily demand increased by 15.7% for the same period, from 267 ML to 309 ML. Total annual consumption of water also increased between 2004-05 and 2005-06 from 51,717 ML to 54,340 ML.
2.4 Summary, Water supply and usage - ACT |
|  |
| | 2003-04 | 2004-05 | 2005-06 | |
| |
| Customers | no. | 131 893 | 134 020 | 136 890 | |
| Maximum daily demand | ML | 323 | 267 | 309 | |
| Total consumption | ML | 52 262 | 51 719 | 54 340 | |
| Consumption per person per annum | kL | (a)156 | 144 | 149 | |
| Rainfall | mm | 463 | 594 | 629 | |
| Length of mains | km | 2 985 | 3 013 | 3 057 | |
| |
| (a) Figures adjusted to account for combined ACT and Queanbeyan population. |
| ACTEW Corporation Limited, 2005-06 Annual Report. |
