The weekend’s rainfall has only added a minor increase to the region’s drinking water supply but has primed catchments for bigger increases over the next few days.
A record dry winter and hot start to spring has resulted in South East Queensland drinking water catchments requiring significant rainfall to saturate the ground to trigger inflows into the region’s dams.
The weekend’s rainfall has added 0.5% to the combined storage levels of the Grid 12 – the 12 key dams that make up nearly 90% of the South East Queensland’s drinking water supply. The increase in dam levels is the equivalent of an extra week of supply based on current consumption.
The Grid 12 is now at 71.7%.
In the past week, about 60mm of rain has fallen in the Wivenhoe Dam catchment, with 100mm recorded in the Somerset Dam catchment and 100mm in the North Pine Catchment.
On the Sunshine Coast the catchment of the region’s largest dam, Lake Baroon, received rainfall of about 65mm.
Seqwater spokesman Mike Foster said if the forecast rainfall over the next couple of days eventuated, drinking water supplies would receive a welcome boost.
“So far, we’ve only seen a minor increase in the region’s combined storage level but if we continue to receive heavy rainfalls those dam levels should start to rise,” Mr Foster said. Mr Foster said the continued wet weather was likely cause a number of un-gated dams across
South East Queensland to spill, particularly on the Sunshine Coast. Wappa and Poona dams were already spilling. Further rainfall could see both Ewen Maddock and Lake Macdonald at Noosa also spill.
He said Seqwater had started operational releases from Somerset dam into Wivenhoe dam with inflows starting into Somerset dam. These operational releases will not result in releases needing to be made from Wivenhoe dam.
Seqwater is continuing to work closely with the Bureau of Meteorology and other agencies to monitor approaching rainfall systems and assess potential dam inflow impacts. Seqwater is also monitoring any impacts to recreation as a result of the weather event.
South East Queenslanders are encouraged to sign up to Seqwater’s dam release notification service, which lets subscribers know when dam releases are occurring or un-gated dams are spilling, or have stopped spilling.
To register for Seqwater free dam release service or for updates on Seqwater recreation facilities please visit www.seqwater.com.au.