The NWT Power Corporation expects it will take 10 days to fix the power line struck by a military helicopter on Monday night.

Lt.-Col. John Casey, air component commander for the Canadian Forces' Exercise Arctic Ram, said the low-flying helicopter was practising surveillance in the area when it "struck a set of wires.... electrical wires of some variety."

Lt.-Col. John Casey, air component commander for the Canadian Forces' Exercise Arctic Ram, says the low-flying helicopter that struck a power line near Yellowknife Monday was practising surveillance.  Lt.-Col. John Casey, air component commander for the Canadian Forces' Exercise Arctic Ram, says the low-flying helicopter that struck a power line near Yellowknife Monday was practising surveillance. (CBC)

The helicopter snapped three integral transmission lines from the Snare hydroelectric system to North Slave communities.

Robert Schmidt, director of hydro operations with the NWT Power Corporation, said crews have been out to the line break 10 kilometres northwest of the Yellowknife airport.

“When we lose Snare, we lose our largest in-feed of hydro and we were able to replace most of that with diesel generation."

Currently, Behchoko is being powered by the diesel plant at Frank’s Channel, and Yellowknife is being powered by the diesel plant at Jackfish Lake as well as some hydro from the Bluefish Dam.

Crews and equipment will have to come from the south to fix the lines.

In the meantime, Northland Utilities, which manages power distribution, is asking people to conserve energy, especially during peak demand hours. It’s asking residential customers to reduce their use of electronics and appliances between 6:30 and 9 a.m. and from 4:30 to 7 p.m.