In "an era of climate change", NZSki has been given approval in principle to substantially boost its artificial snow-making capacity.
In July the Otago Daily Times reported NZSki was planning a multimillion-dollar development of the skifield, the largest in its 26-year history, and the Department of Conservation has since released a report before the final decision is made by Otago Conservator Alan McKenzie.
The report said that the skifield had 70 snow-making machines, which would be boosted to up to 125 machines, increasing snow coverage from 14ha to 36ha once upgrades to the area's trail networks were completed over the next five years.
Because natural snowfall was variable, increasing the number of snow-making machines was "an immediate imperative" to make possible a concrete predetermined opening date each June.
"Greater certainty of opening would allow the ski area to command more pre-bookings for the early winter, a time of high set-up costs and uncertain patronage.
"This benefit was evidenced in the 2012 winter, when artificial snow allowed a limited opening of the ski area prior to any significant natural snowfall," the report said.
To operate the snow machines, up to 400,000cu m of water would be required and it is proposed the water come from the Rastus Burn via the current pumping house and directly from Lake Alta.
The maximum drawdown from the lake would rise to 57cm from the current 15cm.
If the limit was reached, snow-making would be suspended until the stream and lake were naturally replenished.
Under the current allowance Lake Alta was drawn down to the maximum by late June and was not fully restored until the end of August, but under the new concession it would not be restored until late October.
Also proposed is a new chairlift for an area known as "Curvy Basin", a realignment of the skifield's access road to make it safer, a redevelopment of the learners' area and a new car park on land not covered by the current lease.
Public submissions on the report close on November 30, after which a decision would be made as to whether a hearing was required.
NZSki chief executive James Coddington said commercial decisions, such as what type of snow-making machines would be used, had not been made yet and would only be made once Doc had granted consents.
