Water on the way

Friday, 3rd February, 2012

By Paula Doran

The NSW Office of Water has made urgent water releases from the Menindee Lakes as inland tributaries at the top of the Darling system swell dramatically under massive rain.

While the towns hardest hit in southern Queensland and northern NSW were yesterday evacuating ahead of rapidly rising rivers, the Department of Primary Industries was preparing for huge volumes of water to flow into the Darling River and down to Menindee.

The rainfall continued yesterday, causing floods in two major Darling River tributaries, the Gwydir and the Namoi.    

The Gwydir region was particularly hard hit, with 150 millimetres of rain in 24 hours.

At one gauging station upstream of Moree on the same river, 300,000 megalitres of water (more than half the volume of Sydney Harbour) was being measured per day.  

All around the interior in towns more famous as outbackí than riverfront, the SES and Shire Councils were battening the hatches against floodwaters. In the town of Mitchell, east of Charleville, they were expecting a flood to rival the record flood of 1990.  

Further south, St George, a town that made the headlines in last year’s big floods, residents were facing the prospect of two river systems combining in the next two days to create another record watercourse.

And as the list of rain-drenched inland towns continued to mount, water managers began preparing for the fact that much of that water could be in the Menindee Lakes within months.

Brian Graham, Surface Water Manager from the NSW Office of Water, said it was impossible to know how much water would make its way to Menindee.  

“Every flood event is unique. The catchment will respond to different flood events differently.

“Our main objective is to begin work now by increasing the release of flows out of Menindee, which will eventually protect the Menindee township from flooding when the big flows do arrive. We will certainly do everything we can to avoid flooding of low lying houses.”

State Water estimates the flood waters from this week’s flow will arrive in Menindee late next month at the earliest.

But with floodwaters already expected from rainfall late last year, water managers will be operating at peak hour to make sure there is enough space in the lakes to accommodate the large flows.

Releases from Weir 32 have been increased from 15,000 megalitres per day to 20,000, effective immediately.

Meanwhile, in the north of the State, more rain is forecast today.