The private energy company which powers Haast wants to build a second hydro-power scheme there, to meet growing power demand.
NZ Energy proposes using the discharge water from the existing Turnbull River hydro-power station.
This will involve a second water intake to divert water in the event the existing intake or pipeline is damaged or unable to be used, to build resiliency.
It will produce enough power to supply a reasonable level of electricity to the community of Haast while repairs or maintenance are undertaken on the upper intake or pipeline.
The Turnbull scheme was constructed in 1972.
The national grid does not extend beyond Paringa, and so Haast and the community are totally reliant on the power generated from Turnbull.
The current scheme diverts a small proportion of the water from the Turnbull River into a settling basin located within the Venture Gorge.
Water is then conveyed 1.4km to a surge tank located immediately above the station.
Excess water is spilled at this point and re-enters the Turnbull River.
However, there have been a few problems in recent years due to a large flood causing damage and blocking the intake.
There are diesel generators for backup but these have limited capacity.
With the growth in Haast and increasing electricity demand for things such as electric vehicle charging, there is a need to increase the reliability and resilience of renewable electricity supply to the area.
NZ Energy has applied to the West Coast Regional Council for a variation to take water from different locations, though it said it would not take any more than was currently consented.
The land involved in the proposed scheme is private and Department of Conservation stewardship land.
The site is on the true-right (north) bank of the Turnbull River, dominated by the existing road and power-line route, a small section of low native bush and boulder-strewn margins of the riverbed.
It is proposed to bury the first part of the pipeline.
"This electricity will enable the economic, social and cultural wellbeing of Haast community," the application said.
