Dock Lake hope
ADock Lake wetland and wilderness area as well as neighbouring recreational Green Lake are primed to benefit if water spills from Lake Wartook in the Grampians this spring.
Catchment leaders have confirmed that any excess water flowing down Mackenzie River from Lake Wartook would join a 2500-megalitre allocation and any natural run-off flowing into Green Lake.
Their hope is that ‘filling’ Green Lake will open the door to provide Dock Lake, listed as a wetland of environmental significance, with its first drink since 2016.
Dock Lake, smaller than 5350ML Green, can only receive water from an overflowing Green Lake.
Wimmera Catchment Management Authority chief executive David Brennan said a flow of environmental water on top of an allocation already underway would present a major environmental as well as recreational boost for the Green-dock and potentially Wimmera River system.
But he said the top-up would depend on what happened at Lake Wartook.
Mr Brennan said he expected latest storage figures today to reveal another rise in the lake, which last week stood at 76 percent full and is renowned for its efficiency in capturing run-off.
“With the rain we’ve been having Lake Wartook is getting closer to full capacity. If it overflows it goes to the environment and we will be working closely with Gwmwater to ensure it gets through to Bungalally and Burnt creeks and then on to Green and Dock lakes,” he said.
“I was there at the weekend and there was probably a bit over a foot to go. It was significantly higher than at the same time last year and we have our fingers crossed considering October is our largest inflow month.
“I don’t think it would need a huge amount to get water to Dock and it is certainly feasible if the rain continues.
“Apart from watering Dock Lake it would give Green a really good flush.”
The environmental opportunity potential for Dock Lake comes after Gwmwater confirmed recreation supply to Green Lake as well as pipeline-supplied water for scheduled recreation lakes and weir pools across the region.
The corporation offered the supply with Horsham Rural City Council funding and having confidence in the water-resource position after winter inflows to Grampians storages.
Gwmwater managing director Mark Williams said the corporation board recognised the importance of regional lakes and weir pools. He said supply to these water bodies was integral to a Wimmera-mallee Pipeline business case based on recreational and environmental value.
“We have been monitoring our water-resource position closely to ensure that we have enough water to supply our urban and rural customers not just this year, but in the years ahead,” he said.
“Thanks to a relatively wet winter we are thrilled to now be in a position to make a combined 5780 megalitres available for recreational use across the region.”
A five-year Street Ryan study has outlined benefits based on the impact of recreation water in the WimmeraMallee. Researchers determined the annual economic value of recreation to be about $30-million.
Mr Williams said as well as being an environmental and recreational haven for locals, recreation lakes and weir pools were proving popular destinations for visitors.
The top-up of Green Lake will be its first allocation since 2019, the first significant inflow since 2016 and increase the lake’s level by 1.6 metres to 2.7 metres.
Horsham Rural City Council used a budgeted $60,000 to pay for the water.
Horsham mayor Robyn Gulline said the Gwmwater offer would shore up recreational activities at the lake for at least the next 12 months.
“A full Green Lake this summer is great for our municipality. Besides its enormous recreational benefits to the community, it will also enhance business and tourism for the Wimmera,” she said.
“The pandemic has restricted recreation activities across the past 18 months. So to have guaranteed access to such a popular lake this summer is a terrific boost for our community.”