The Five Options
Option 1: Luggate Dam Hydro Scheme
• Concrete gravity dam two kilometres downstream from the Luggate Red Bridge.
• 8 possible dam sites near the Devil's Nook under investigation.
• Powerhouse would be located immediately downstream, similar to existing Clyde and Roxburgh dams.
• 3 steel penstocks feeding the turbines.
• Dam reservoir would submerge about 230 hectares extending up the Clutha Valley to near Albert Town.
• Reservoir level about 271 metres above sea level.
• Studies are underway to determine the extent of reservoir inundation.
• Capacity 86 MW capable of generating about 500 GWh annually.
• Roading; about 3.5 kilometres of local roads would be flooded and would need re-aligning.
• The Luggate Red Bridge would be submerged and would need to be replaced.
• Project construction time about 4 years.
Option 2: Queensberry Dam Hydro Scheme
• Concrete gravity dam on the Clutha River, near Poison Creek at Queensberry.
• A canal is required to a powerhouse downstream to achieve a generating 'head'.
• There are two canal options; a 12 kilometre canal to Gravelly Gully or a 9.5 kilometre canal to Kidd Creek.
• Two powerhouses in total; one at Gravelly Gull or Kidd Creek, and one at the dam.
• The dam reservoir would submerge about 220-hectares extending up the Clutha Valley to near Luggate.
• Reservoir level about 245 metres above sea level.
• Studies are underway to determine the extent of reservoir inundation.
• Capacity 160 MW capable of generating about 850 GWh annually.
• Roading; 3 kilometres of local roads flooded would need re-aligning, and 12 kilometres of canal access road would be needed.
• Transmission lines would be required in the Upper Clutha Valley.
• Project construction time 4-5 years.
Option 3: Beaumont Dam Hydro Scheme
• Concrete gravity dam on the Clutha River, approximately four kilometres upstream from the Beaumont Bridge.
• A powerhouse would be built in the riverbed with spillways on the eastern side.
• The dam, powerhouse and spillways, would be similar to the Clyde and Roxburgh dams.
• The dam reservoir would submerge about 620-hectares extending up the Beaumont Gorge 23 kilometres to Miller’s Flat.
• The Island Block area downriver from Miller’s Flat would also be submerged.
• Reservoir level about 69 metres above sea level.
• Studies are underway to determine the exact extent of reservoir inundation, but it is thought the inundation would be similar to that which would result from a dam at Tuapeka.
• Capacity 185 MW capable of generating about 1,070 GWh annually.
• Roading: Sections of the Miller’s Flat Beaumont Road and Millennium Trail would be submerged. Six kilometres of State Highway 8, and seven kilometres of local roads would need to be replaced.
• Transmission lines would need to be upgraded, as the Halfway Bush to Roxburgh lines do not have the capacity to carry an additional 185 MW.
• Project construction time 4-5 years.
Option 4: Tuapeka Dam Hydro Scheme
• Concrete gravity dam on the Clutha River, approximately two kilometres upstream from Tuapeka Mouth.
• A powerhouse would be built downstream of the dam.
• The dam, powerhouse and spillways, would be similar to the Clyde and Roxburgh dams.
• The dam reservoir would submerge about 3,400-hectares extending about 50 kilometres up the Rongahere Gorge, over the Beaumont Valley and up the Beaumont Gorge to Miller’s Flat.
• Beaumont township would be submerged.
• The Island Block area downriver from Miller’s Flat would also be submerged.
• Reservoir level about 69 metres above sea level, or about 50 metres above the existing river level.
• Because of earlier studies by ECNZ, the area of inundation is more accurately known.
• Capacity 350 MW capable of generating about 1,950 GWh annually.
• Roading: Nine kilometres of State Highway 8 would be submerged and 39 kilometres of local roads. Re-aligning State Highway 8 would involve the construction of a bridge or causeway across the reservoir.
• Transmission lines would need to be upgraded, as the Gore-Roxburgh, Invercargill-Roxburgh and Gore-Halfway Bush lines do not have the capacity to carry an additional 350 MW. Upgrades to the South Island network would potentially be required.
• Project construction time about 5 years.
Option 5: No dam.
Additional Facts: Hawea Dam Hydro Scheme
• Retrofit of existing dam to install 17 MW generating plant, consented.
• 95 MW development involving canal construction to a powerhouse near Albert Town utilising a 75 m head.
• There are two canal / powerhouse options; a canal to a powerhouse on the lower Hawea River, and a canal to a powerhouse on the Clutha River.
