The wood stave pipeline originally joined two steel penstock pipes which dropped to the power station building in the Yolande Valley below. Due to the efficiency of the scheme another penstock pipe was added in 1919. Due to internal deterioration these pipes were replaced in 1969 with a single steel pipe, by contractor John Holland. This replacement coincided with major refurbishment of the power station building, renewal of sections of the Lower Power Scheme wood stave pipeline, replacement of the transmission lines between the power station and the Queenstown substation, and post-stressing of the Lake Margaret dam wall.