Lachlan Regional Water Strategy

The following frequently asked questions relate specifically to the Lachlan Regional Water Strategy.

What are the effects of the Wyangala dam raising project on downstream users, landholders and the environment?

WaterNSW has been tasked by the NSW and Australian governments to deliver the Wyangala Wall Raising Project. Raising Wyangala dam wall and increasing the storage capacity will substantially contribute to improving water security and drought resilience for the Lachlan Valley. The project includes:

  • raising of the embankment and downstream rockfill to add an additional 650 GL of storage
  • raising the spillway and intake towers of the dam by a nominal 10 m.

Environmental impact assessments are currently underway. An environmental impact statement process with formal public consultation, as part of normal planning and development processes, will be undertaken in early to mid-2021.

While this is a project listed under the Water Supply (Critical Needs) Act 2019, it does not preclude it from undertaking environmental, heritage and planning assessment. WaterNSW are committed to understanding, reducing and offsetting the environmental impacts of the project including those related to inundation of property, changes to flow regimes which flush the bottom of the system and provide water to wetlands, and effects on native fish passage.

Visit WaterNSW for more information on the project.

What are the effects of the Lake Rowlands to Carcoar Dam pipeline project on downstream users, landholders and the environment?

The NSW Government has committed to developing a business case to explore the option of building a water transfer pipeline from the Central Tablelands Water-operated Lake Rowlands Dam to the larger WaterNSW-operated Carcoar Dam. The preferred option will also undergo further assessment with an Environmental Impact Statement (EIS) involving technical, hydrological, environmental, biodiversity, cultural and economic feasibility studies, and further stakeholder consultation.

Visit WaterNSW for more information on the project.

What is involved in the Lower Lachlan efficiency measure proposal? What are the effects on downstream users, landholders and environment?

The ‘Lower Lachlan efficiency measure’ proposal would investigate opportunities for a more efficient alternative water supply to landholders (including stock and domestic users) in the lower Lachlan region (along the Muggabah, Merrimajeel, Merrowie, Booberoi and Willandra creeks). In particular, the option would consider replacing current replenishment flows in these creeks with a piped scheme and the development of groundwater sources to meet demand and thereby reducing transmission losses.

The full effect of the proposal would need to be investigated. During consultation on WaterNSW’s Lachlan valley water security study, landholders raised concerns about alternative water delivery arrangements. In addition, the construction of a piped scheme would remove replenishment flows from these creeks and the creeks could dry out during periods of low rainfall. These creeks provide important environmental and cultural functions. The effects of removing replenishment flows on ecosystems, native fish and native plants and animals needs to be further investigated. Effects on groundwater sources, including to recharge, would also need to be assessed.