Mixed rainfall results for Sydney's drinking water catchments - Minister Phillip Costa MP - 1 April 2009
NSW Minister for Water, Phil Costa, today said rainfall in metro Sydney is delivering mixed results across the drinking catchment.
The 9050 square kilometre Warragamba Catchment received an average 14 millimetres in the 24 hours to 9am, with isolated falls as high as 52 millimetres in Oakdale and 63 millimetres in Katoomba.
“In one day we’ve had about one sixth of the long term median April rainfall for the Warragamba Catchment,” said Mr Costa.
“The rain is mainly along the eastern coast which means the smaller, coastal catchments are receiving heavier falls."
The Upper Nepean Catchment, which supplies Cataract, Cordeaux, Avon and Nepean dams, received 41.6 millimetres overnight. This is almost half the median April rainfall.
The Woronora Catchment, which supplies water for the Sutherland region has also received about half of its median April rainfall with 49.5 millimetres overnight.
Mr Costa said dam levels would be measured tomorrow afternoon, but it would take much more rainfall to see a significant change.
“We’ve had below average rainfalls over summer and through March,” he said.
“Last week total storage levels were at 58.3 per cent. This is the lowest we have experienced since November 2007. Warragamba Dam was at 55.5 per cent of capacity.
“The ground is dry so a lot is being soaked up. What we need is consecutive days of rain to allow for flows to reach the dams.
“We would need to see at least five days of 35 millimetres per day rainfall across the entire 16,000 square kilometres of drinking water catchments to see total storage rise to 70 percent of capacity.
"These catchment areas stretch south almost to Cooma, and as far north as Lithgow.”
According to Bureau of Meteorology, showers are expected for the remainder of today and tomorrow.
