Five gates open at Wivenhoe Dam
JUST as a brief respite from the rain allowed a raging Brisbane River to mellow, a full-blown release from Wivenhoe Dam brought things back to normal.
Water Grid operators opened all five gates yesterday following persistent rain through December which, despite on-going minor releases, had filled the dam to about 122 per cent of its capacity.
As of yesterday, Brisbane’s main water storage was packing a massive 1,432,791 megalitres – almost 300,000 megalitres more than its normal 1,165,238 capacity.
A quick look back at Wivenhoe Dam’s levels during the past three years shows just how quickly the south-east corner has gone from a drought-ravaged dust pit to a sea of green.
In December 2007, Wivenhoe Dam was at a critically low 15 per cent. By the end of the next year it had climbed to 32 per cent, and by the end of 2009 it had doubled again to 62 per cent.
Now with so much water the State Government has no option but to send it out to sea in case of more flooding.
Authorities had been planning to empty the dam of its flood storage compartment much earlier, but had to hold off because the Lockyer Creek and Brisbane River were already overflowing from the rain.
Substantial releases from Wivenhoe will continue until the weekend to empty the flood storage compartment.
“With the catchments now wet, it is important that the flood compartment be emptied in anticipation of any future inflows,” a Water Grid spokesman said.
“Delays accessing viewing stations at Wivenhoe Dam should be expected due to heavy sightseeing traffic.
“Surrounding non-sealed areas are saturated and there is a real risk of vehicles getting bogged if they leave bitumen roads.”
Enormous volumes of water will be sent down the river as a result of the release and Twin Bridges, Savages Crossing, Colleges Crossing, Kholo Bridge and Burton Bridge will continue to be inundated until the weekend.
Mt Crosby and Fernvale bridges were not expected to be flooded by dam releases.
“Based on current Bureau of Meteorology advice regarding reduced rain and lower tides, Brisbane River levels are expected to remain below the peaks of last week,” a Water Grid spokesman said.
Flows from Somerset Dam into Wivenhoe Dam were expected to reduce today.
For information on dam releases call 1800 613 122.