SA Water has begun closing gates on the barrages that connect the Murray River to the Coorong wetlands and the ocean as flows along the river drop.
Key points:
- All of the operational gates were opened in December to let the Murray River floodwaters pass through
- Flow levels into South Australia are dropping rapidly
- The closure will be managed to maintain water levels in the Coorong and Lower Lakes
All 570 operational bays on the five barrages were opened in December as the peak of the floodwaters made their way down the River Murray.
It was the first time so many gates had been open at once, since the break of the Millennium drought in 2009.
Senior manager of River Murray operations with SA Water, Garry Fyfe, told ABC Radio Adelaide yesterday the work was “the start of the end of the floods” and there was now a very quick drop away in flows all along the river.
The flow rate into the state on Tuesday was 48,524 megalitres per day, compared to the peak of 185.9 gigalitres per day at Christmas time.
Mr Fyfe said the decision to close the first of the 1.5-tonne concrete gates was to ensure that water levels didn’t drop too quickly around the Lower Lakes and Coorong.
“This is important to stop seawater from flowing upstream into the Lower Lakes, while maximising the ability for river water to pass through to the Murray Mouth,” he said.
Gates along the Boundary Creek and Mundoo barrages are already back in place and staged work will begin at the Goolwa, Ewe Island and Tauwitchere barrages over coming weeks.
The barrages were not damaged during the period of high flows, but Mr Fyfe said weirs and locks upstream did sustain some damage.
He said the rare simultaneous opening of all of the operational bays had attracted thousands of locals and tourist to the Goolwa Barrage over recent months.
