Category Archives: Background Information

Background Information

Oven Mountain Pumped Hydro – Public Information Forum Report

The Public Information Forum on Saturday 19 November was attended by 100 Macleay residents and three OMPHS representatives. SOMR organised this event to provide an opportunity for the proponents of the scheme to give a comprehensive presentation of the plans as well as for representatives of the First Nations community, environmentalists and local residents to ask questions and voice their concerns.

After the initial introduction of the program, SOMR founding member Arthur Bain, handed over to the Forum Moderator Dr Tim Cadman, Research Fellow at Griffith University and Mid North Coast resident.

First up, SOMR Secretary Rupert Milne Home explained the planning process.

The Forum was timely, because the planning process for the project is at a significant stage with the Environmental Impact Statement (EIS) and the Development Application (DA) to be finalised and lodged with Department of Planning and Environment (DPIE) soon.

OMPHS representative Patricio Munoz explained that, while they intend to lodge the documents by the end of the year, they do not expect the public exhibition by the DPIE before February 2023. These documents will consist of several hundred pages with the public given the required 28 days to comment and write submissions.

Patricio then gave an overview of the project using some of the maps and illustrations which can be found on their website He emphasized that the Macleay River will not be dammed and that ‘fast tracking’ the project does not mean that there will be short cuts in the planning process.

The OMPHS representatives had to leave after their presentation with very little time to answer questions at the meeting. Therefore, questions were later taken from the floor to be sent to OMPHS. (See below)

The speakers for the Dunghutti Nation, Warren Roberts and Clarrie Hoskins, as well as members of the audience stated repeatedly that the consultation with the First Nation community so far is unsatisfactory as is the research into the impact on culture and country. In the words of Warren Roberts: “The consultative process is no way sufficient for us to come on board”.

Addressing one of SOMR’s main concerns, Arthur Bain presented a recently completed report by Professor Scott Johnson of Southern Cross University. Based on water samples taken in Bellbrook by Arthur on behalf of SOMR over several years, it clearly shows how the presence of antimony and arsenic levels in the river are impacted by rain and fire events. Therefore, any soil and rock disturbance during the construction and operation of the Oven Mountain Pumped Hydro project may have the potential to contaminate the Macleay River. Addressing prevention of this contamination in the planning stage is of utmost importance. (Find the presentation on One Drive!AnFAkxeTrT19qE9h0kgsafMSSVrW?e=Y60ByT )

The final speaker, ecologist Mark Graham has spent most of his life in the North Coast and Mid North Coast. He described the Macleay Valley as central to the Great Eastern Ranges, one of the richest areas of biodiversity in the world with globally significant conservation values. The valley is a vital link in the wildlife corridor extending from Gippsland to Queensland. Mark displayed a huge list of threatened species that rely on this corridor. He is concerned the pumped hydro project will cut into the corridor and weaken its critical role in the protection of biodiversity.

In conclusion, Mark pointed to alternative pumped hydro options in less vulnerable environments. One such project is being explored in abandoned coal mines in the Hunter Valley.

Overall, the forum was a good introduction to the proposed project, however many questions remain.

Here are the questions from the floor after OMPHS representatives had left the Forum. They are listed in the order of asking and will be given to OMPHS.

  1. What are the provisions for decommissioning and rehabilitation of the site at end of life; and who will pay for it?
  2. What are the statistics on evaporation during high temperatures, low flow and drought?
  3. What is needed to upgrade the existing transmission lines and who will pay for that?
  4. What will be done to manage the contamination of Antimony and Arsenic etc. (naturally) in the geology of the area?
  5. What are the Alternatives to this Project?
  6. Why cannot a large battery storage be built in Armidale (near the sub-station)?
  7. How much Pumped Hydro Storage is planned for the New England Renewable Energy Zone (REZ)? – Any other PHS projects proposed here?
  8. Will the Proponent commit to a Non-State Significant Development pathway, to allow for greater community engagement? 1.
  9. Can the Proponent guarantee no adverse impact on the Carrai water table?
  10. Where are the profits going?
  11. Why build in such a culturally significant area?
  12. Please confirm dates (and extent) of Aboriginal Community Consultation?
  13. Have OMPHS considered purchase of the Oakey River Hydro Scheme project? – If not, why not?
  14. To DPIE and Proponent: Why make staged pathway? 2
  15. Why was this site chosen, and was there any personal interest involved?

More About Oven Mountain Pumped Hydro

While SOMR is primarily concerned about the impact of the pumped hydro scheme on the Macleay River, at this stage of the development it is most important that the community is correctly informed on a number of issues.

In a recent interview reported in the online and print editions of The Macleay Argus, Melinda Pavey, MP for Oxley, encouraged the Macleay residents “to learn for themselves” about the Oven Mountain Pumped Hydro project. The problem is that many ‘facts’ in the interview were not correct; adding to the misinformation in the community. It seems neither Ms Pavey nor the Argus reporter have checked their facts.

In a letter to the Macleay Argus SOMR addressed several of the issues. Read it here


The two quarries are located in an existing gravel flood-channel of the Macleay River, which fills with water with a river rise of about 2.5 meters. This then forms a large island of about 20 hectares between the flooded channel and the lower river channel. The velocity of the water flowing though the quarries, increases with the rise in water level until it matches the main river flow. (Refer Images 1 & 3 below.) When the river height reaches about 10 meters the whole island (right hand side of Image 2 below) is covered by water.

The Development Approvals for the quarriers were issued by Council in 1997, with only six Conditions relating to extraction of the gravel and compliance with Department of Water Conditions. This; in-spite of the long existent NSW State government Policy, ‘The NSW Sand and Gravel Extraction Policy for Non- Tidal Rivers’ (1992).

The ‘Approvals’ were issued under “Existing Use Rights” as the quarries had been operating for several years and excavation was limited to the existing approved area. The Environmental Planning and Assessment Act defines Existing Use Rights as: “One which began legally but would now be prohibited”.

The quarries have been operating under the 1997 Approvals for about 25 years and, to the best of our knowledge, there has never been an Environmental Impact Study carried out to assess the environmental impact the quarries on the Macleay River including: river morphology, antimony and arsenic mobility, as well as the fish and wildlife that are part of the local ecosystem. Or addressing any of the 6 mechanisms identified in The NSW Sand and Gravel Extraction Policy for Non-Tidal Rivers’ (1992).

SOMR’s concerns are that the continued operation of the extraction is creating a deep channel in the gravel bed, approximately 2 meters deep at the upstream end. As water flows over this excavated edge, it erodes the gravel bed further upstream and changing the water flow within the existing gravel bed. (Refer Image 1 below.) The extended reduction in the height of the existing gravel bed then has the potential to continue to extend upstream from the excavated area, potentially meeting up with the main river flow channel and changing the river course.

As there is no set length of time within the DAs for the quarries to cease operation, the question is, how long can the quarries continue to operate without complying with current environmental requirements? There have been numerous breaches of the DA and Licence Conditions over the years which have been ‘overlooked’ by council and the annual inspection by the understaffed Department of Water (now National Resource Access Regulator).

We believe that now is the time to urgently review this situation of operating under historic and out-dated “Existing Use Rights” Approvals and 1997 Conditions, given; the increased number of flood events impacting the Macleay River, due to climate change and the increased potential for major impacts on the stability and health of the river and those people and industries impacted.

1. A knick-point developed as a consequence of steep-batter quarrying eroding upstream from the quarry face following flooding, impacting on the natural rates and magnitude of change in the gravels of the flood channel; 6th Aug 2021.

2. Site of gravel quarries lower centre- left of image.

3. Flooded quarries showing extraction is affecting the active upper river channel of the river.

4. Gravel movement from upstream erosion after flooding; 20th Dec. 2021.


  1. The above is a summary only, as to include all the information on file (copy of DAs, correspondence with Council and Department of Water. Images of Quarries etc) would create a very extensive article) Some images have been included to show the location of the quarries, the extent of the excavation and the altered water flow being created by the operations.
  2. An assessment of the ‘Turners Flat Geomorphological Context’ is linked to this article:

3. A relevant extract of the “Sand and Gravel Extraction Policy for Non-Tidal Rivers” (1992) is also linked to this article for further background information:

Notes 2 & 3 have been prepared by Michael Pemberton, a SOMR Committee Member, with many years of experience in fluvial-morphology.