The Northwest Territories Power Corporation is starting to look at a massive project to connect hydro systems in the territory.

The project’s costs would dwarf those of the Dehcho Bridge construction, which ballooned to over $200 million.

NT Hydro is doing a preliminary study of running a hydro line around the west side of Great Slave Lake. The line would link hydro systems in the North and South Slave, and bring power to the diamond mines.

"It's backbone infrastructure that at some point is required for the north to enjoy the same kind of energy savings and pricing for power that's felt in most of the interconnected parts of Canada. If we're ever going to get to a place where we can ...attract industry and grow our economy then at some point we need to make this investment," said Andrew Stewart, the manager of business development for NT Energy.

Stewart said the work is very preliminary — it will be at least two years before regulatory applications are filed, if the project gets that far.

He said it would require large investments by the territorial and federal governments. The 1,000-kilometre transmission line alone would cost more than $400 million.

The power corporation recently spent $13 million trying to bring hydro power to the diamond mines. That plan involved running a transmission line around the east end of Great Slave Lake.

It failed when the corporation was unable to secure long-term power purchase agreements with the mines.