The timetable for a new $900 million power scheme on the lower Waitaki River has been reduced, but Meridian Energy has not yet decided if it will build it.
Initially, Meridian proposed a 15-year timetable to obtain resource consents, plan and construct the North Bank Tunnel Concept scheme, meaning it would not be in operation until 2023 at the earliest.
Yesterday, it indicated it would need only 12 years, with the scheme finished by 2020.
The shorter time-frame emerged in evidence presented by Meridian to an Environment Canterbury (ECan) resource consents hearing in Christchurch yesterday.
The hearing follows an interim decision by three ECan commissioners to grant Meridian four water-only resource consents for the scheme, subject to outstanding aspects of some of the consent conditions being resolved yesterday and today.
However, that is only the first step before Meridian makes any decision on whether the scheme will be built.
That would be based on an economic assessment of the scheme.
Meridian's water infrastructure development manager, Nick Eldred, said the development programme for the scheme had been reviewed and Meridian now believed 12 years, not 15, could be the minimum period for giving effect to the consent.
The next phase of work - an engineering feasibility study to determine the preferred scheme layout and design - would start in the middle of next year, in conjunction with any appeals over the water-only consents to the Environment Court.
That would take a year to complete.
That would be followed by lodging applications for land-use consent with the Waimate District Council to build and operate the scheme, taking about a year for final decisions.
Another year was allowed for any appeals to the Environment Court over those consents.
Detailed design and choosing a contractor to build the scheme would take a further two years.
Mr Eldred estimated it would then take six to seven years to build the scheme.
"It may be possible that stages of the process take less time or are truncated," he said.
However, there was still a high degree of uncertainty over whether time-frames could be longer.
"Given the scale of the proposal . . . 12 years really is the shortest prudent minimum lapsing period," Mr Eldred said.
The water-only consents would have to be exercised within 12 years, or would lapse.
North Bank scheme
Progress to date on the tunnel power scheme.-
•An interim decision by Environment Canterbury on December 1 granted four water-only resource consents to Meridian Energy Ltd, applied for in October, 2006, to divert, take, use and discharge water for a new power scheme on the lower Waitaki River.
•The interim decision was granted provided outstanding aspects of the conditions on the consents could be satisfied at a hearing in Christchurch yesterday and today.
•North Bank Tunnel Concept scheme is to take up to 260cumecs of water from Lake Waitaki into a 34km tunnel with one powerhouse generating between 1100 and 1400GWh a year.
•Commissioners: Former Environment Court judge Prof Peter Skelton (Christchurch), environmental consultant Mike Bowden (Kaiapoi) and freshwater scientist and ecologist Greg Ryder (Dunedin).
•Hearings conducted over 23 days in Timaru last year and two days in Christchurch this year.
