Thanks to a dump of rain into the Shoalhaven catchment in December, the region’s water stores have been replenished and secured, to the end of summer.
That the region has so far escaped punishing water restrictions is proof that the Shoalhaven catchment system is “very” secure, says Shoalhaven Water’s operations manager Andrew McVey.
“We came within two weeks,” he said.
“It shows that we have a very secure water system. We have a very large catchment so it doesn’t take a lot of rain to maintain our supply for the Shoalhaven system.”
That said, dry conditions and a drop in river flows, meant Shoalhaven Water was forced to stop pumping out of the Shoalhaven River in November.
That meant, that for the period that the pumps were off, all of the region’s water was being drawn out of Bamerang Dam.
“We had been drawing down the Bamerang Dam from November (but) we had some decent rainfall in December at Mount View, out around the Goulburn and Braidwood areas. Our catchment area is big so over a couple of days that water moved down to Tallowah Dam and on to Shoalhaven at Bamarang Dam, where we pump out of the river,” Mr McVey said.
That dump of rain was enough to spur river flows, which allowed Shoalhaven Water to turn its pumps back on.
“As the river was high we were able to pump out of the Shoalhaven River into Bamarang Dam,” Mr McVey said.
“It had gone down between one and two metres but as of today the Bamarang Dam is 100 per cent full. We’ve got enough to get us through to the end of the summer, even if it doesn’t rain.”
Mr McVey said the likelihood of rain is “average to above average”.
“It’s very hit and miss,” he said.
Shoalhaven Water must stop pumping when river flows reach 90 mega litres per day.
River flows peaked on December 6, at 1603 mega litres per day but by yesterday had dropped back to 96 mega litres per day. However, a small amount of rain in the Kangaroo Valley catchment increased flows back to 180 mega litres today.
“Normally we are tracking up around the 400 mega litres per day mark,” Mr McVey said.
“Once we get below 300 mega litres we start to think about what’s happening.”
Read more: https://www.ulladullatimes.com.au/news/