A tourism group has joined the growing opposition against a plan by Newfoundland and Labrador's public energy corporation to build a massive transmission line through Gros Morne National Park.

Nalcor last week released details of its environmental submission on how it would draw power from the proposed $10-billion Lower Churchill hydroelectric megaproject in Labrador to Newfoundland.

If approved, Nalcor would erect a string of 40-metre-high transmission towers through 65 kilometres of territory in Gros Morne, which UNESCO has designated as a World Heritage site.

Bruce Sparkes, president of Hospitality Newfoundland and Labrador, said it is hard to describe how important the park is to the tourism industry.

"It's part of the pie that makes up the tourism industry in Newfoundland and Labrador, and it in itself is a major, major, piece of that tourism pie," Sparkes told CBC News.

Nalcor said its proposed towers would follow an existing route of smaller transmission lines.

But Sparkes said that would still be disruptive to the park, a key draw on Newfoundland's west coast.

"Running towers in front of dynamic and dramatic landscape is going to take away from the natural beauty of it," Sparkes said.

"From a photographic, awe-inspiring point of view, it's going to take away that. And who wouldn't say, 'Gee, too bad they put that pole line there?'"

Parks Canada has already spoken out against the plan. Some residents in the Gros Morne area are also joining the opposition, which could pose problems for Premier Danny Williams, who has been pitching the hydroelectric resources of Labrador as a green alternative to carbon-based emissions.

Speaking with reporters last week, Williams maintained that routing the lines through the park — the easiest point of access along the Long Range Mountains of the island's Northern Peninsula — will be worth it.

"The reason that those lines are actually going through that park and the existing transmission corridor is to take out the dirty emissions that are coming from the Seal Cove-Holyrood plant," said Williams, referring to an oil-burning generating plant in eastern Newfoundland.

"So if we replace those 600 megawatts, then obviously from a climate change and a green perspective, this is a very, very good thing," said Williams, adding that Canada and the new Obama administration in the U.S. are seeking cleaner sources of energy.

The environmental review process for Nalcor's proposal will take more than one year to complete.