EDF seeks approval for 4GWh pumped hydro plant in NSW

EDF Power Solutions Australia has referred its proposed Wala Wala Pumped Hydro Energy Storage project for assessment under Australia's federal Environment Protection and Biodiversity Conservation (EPBC) Act. The project would be a 300-400MW facility offering 10-hour duration storage, providing between 3,000MWh and 4,000MWh of capacity.

Located in the Dungowan Valley near Ogunbil in New South Wales, the project would use two new off-river reservoirs connected by an underground pipeline and a hydroelectric power station. Water would be pumped from a lower reservoir near Dungowan Creek to an upper reservoir at about 1,131 metres elevation during low-demand periods. It would then be released to generate electricity during peak demand.

The plant would connect to the grid via a new substation and a 330kV transmission line linking to Transgrid's existing Line 85 near Bendemeer. EDF is also considering a future connection to EnergyCo's proposed New England Renewable Energy Zone transmission line.

Project timeline and water supply

Construction is expected to begin in early 2029 and last four to five years. Commercial operation is targeted from mid-2033, with an operational lifespan of around 100 years. According to the referral document, the project would support the New South Wales Electricity Infrastructure Roadmap and address what the Australian Energy Market Operator's 2026 Integrated System Plan calls an "urgent need for utility-scale storage."

Water supply arrangements are still under investigation. The referral indicates the project will likely draw at least part of its water from the existing Dungowan Dam. This could be via a new pipeline or the existing Dungowan pipeline, subject to ongoing consultation with Tamworth Regional Council.

Environmental assessment and species impact

The project's biodiversity assessment identified 80 threatened species under the EPBC Act with potential to occur in the area. Of these, 66 were assessed as having at least a moderate likelihood of presence and, applying a precautionary principle, are treated as likely to be significantly impacted.

Species considered most at risk include the Regent Honeyeater, Koala, Greater Glider, Large-eared Pied Bat, and Spot-tailed Quoll. The assessment also identified 26 threatened flora species. Two threatened ecological communities were confirmed present: the critically endangered White Box-Yellow Box-Blakely's Red Gum Grassy Woodland and Derived Native Grassland, and the New England Peppermint Grassy Woodlands.

No survey work has yet been conducted across the transmission investigation area. The referral relies on a desktop assessment for that component, pending further field investigation.

New South Wales pumped hydro pipeline

The Wala Wala project adds to several pumped hydro developments moving through New South Wales' approvals pipeline. The state is seeking long-duration storage capacity ahead of coal plant retirements.

In July 2026, the state government granted planning consent to the 3.6GWh Stratford Pumped Hydro and Solar project. Developed by Gloucester Coal, a Yancoal Australia subsidiary, at a former open-cut coal mine near Gloucester, it pairs a 300MW pumped hydropower station with a 320MW solar array. The AU$1.8 billion project repurposes existing mine infrastructure.

Stratford was one of three projects granted Critical State Significant Infrastructure status in New South Wales in 2024. The others were AGL and Idemitsu Australia's 250MW Muswellbrook project and EnergyAustralia's 335MW Lake Lyell facility.

The state government extended that designation in February 2026 to two more projects totaling 22,000MWh of storage capacity. These were ACEN Australia's 1,000MW/11,990MWh Phoenix project near Mudgee and ZEN Energy's 2,000MW/16,000MWh Western Sydney project at Lake Burragorang. Both were identified through feasibility studies by state-owned water utility WaterNSW.

The critical infrastructure designation provides simplify planning pathways. The Wala Wala referral notes this status has been applied to comparable pumped hydro projects in the state, though it has not yet been granted to the Dungowan Valley development.