The New South Wales (NSW) Government has committed to progressing investigations into the raising of the Wyangala Dam, with WaterNSW set to start work in the near future.
The 10m raising of the wall was identified in WaterNSW’s Lachlan Valley Security Study as a preferred option for improving drought and flood management in the region.
The study found that raising the dam wall increases the capacity to hold water in periods of surplus and deliver controlled release when water is needed. Crucially, it provides increased capability to manage flood events.
The Lachlan Valley is one of the most drought and flood prone areas in the state, having endured the Millennium Drought of the 2000s and significant flooding in 2016. The inability of the water system to mitigate these events has adverse economic, social and environmental impacts for the region’s water-dependent agricultural and mining industries.
As part of any planning process WaterNSW will conduct extensive consultation with the community and stakeholders, both upstream and downstream of the dam.
WaterNSW, the state’s bulk water supplier and system operator, has already undertaken preliminary work to examine the prospect of raising the dam wall.
The proposal to raise the Wyangala Dam wall follows the NSW Government’s announcement to fund a business case for building a 12km pipeline from Lake Rowlands Dam to Carcoar Dam, which was also identified in the Lachlan Valley Water Security Study.
Andrew George, WaterNSW’s Executive Manager Water Solutions and Market Strategy, said, “Raising the Wyangala Dam by 10m would deliver an extra 650GL of storage capacity in addition to the existing storage volume of 1218GL.
“The Lachlan Valley Water Security Study identified infrastructure solutions to the water delivery system in Lachlan Valley, which needs improvements in capacity and capability to meet the challenges of drought and flood.
“Our study shows that raising the dam wall at Wyangala increases the capacity to capture and hold water in periods of surplus flows and regulate the release of stored water when it is needed. It also provides increased capability to manage high inflows and flood events.”
The Lachlan Valley was identified by the NSW Government in its State Infrastructure Strategy 2014 Review as the first of four ‘priority catchments’ for the investment and delivery of critical water infrastructure projects over the next decade.
WaterNSW’s infrastructure solutions in the Lachlan Valley – including raising the dam wall at Wyangala Dam – aligns with the objective to deliver water security for communities and customers in regional NSW.