Some areas of Lake Tekapo will get a temporary electricity supply when supply is cut on May 18 for 10 hours so Transpower can carry out maintenance.
The outage, scheduled from 7am to 5pm, will cut power to areas from Tekapo to Mt Cook.
Transpower spokeswoman Rebecca Wilson said the outage was a combination of four-yearly maintenance work as well as some project work.
"Transpower is working with the local lines company, Alpine Energy, around the provision of generators to some critical areas of the Tekapo township. A total of three generators are planned for installation to supply critical services within the central business district at no cost to the consumer," she said.
At least one major tourist tourist attraction in the area would be seriously affected by the outage. The Alpine Springs complex, which operates an ice skating rink and hot pools, could not afford to lose electricity for a day.
Ms Wilson said having a day-long outage reduced the need to have several outages in the same year to undertake work on the transformer equipment at Tekapo.
The work would help to maintain security of supply and provide a greater level of safety for operational staff.
The outage would occur because the Tekapo area was serviced by one transformer, a situation faced by several places throughout New Zealand, she said.
The cost of installing another transformer would likely exceed $1 million, a cost that would be paid directly by the region, she said.
