EDMONTON -- Parks Canada should reject a plan to build a hotel on the shore of one of the most scenic lakes in the country's national parks, say three former senior staff.

An open letter released Wednesday says allowing a private developer to build a 66-room hotel and 15 tent cabins at Maligne Lake in Jasper National Park would violate well-established policy and open the doors to similar projects that would degrade the wilderness experience.

"The Canadian people, Jasper and other national park ecosystems and Parks Canada have nothing to gain and plenty to lose if this development is approved," says the letter to federal Environment Minister Leona Aglukkaq.

The missive is signed by Nikita Lopoukhine, a former director general of Parks Canada; Stephen Woodley, the agency's former chief ecosystem scientist; and Kevin Van Tighem, former Banff National Park superintendent.

Maligne Lake is the world's second-largest glacier-fed lake. Its 22-kilometre length is ringed with spectacular peaks and its shores are home to grizzly bears and caribou. A view of the lake's Spirit Island was featured on the old $5 bill.

About 2,000 people a day visit Maligne's aquamarine waters in high season.

For decades, a company called Maligne Tours has offered boat excursions on the lake along with other services such as a cafeteria and a store. In 2012, Maligne Tours submitted a proposal to Parks Canada to upgrade those facilities.

In addition to the hotel and tent cabins, the company wants to restore a historic boathouse, add a restaurant and lounge and offer interpretive activities. Maligne Tours says those attractions would increase the lake's appeal to urban youth and to new Canadians -- two groups Parks Canada is keen to reach.

The upgrades would also bolster the company's bottom line. It says demand for boat tours has fallen by about half since 2005.

"Maligne Lake is an authentic Canadian heritage destination which will be sustained as a pristine place offering the best heritage and adventure experiences in Canada," says the company's proposal.

Lopoukhine said he and his colleagues have no objections to much of the company's plan. But allowing hundreds of guests and staff to remain at Maligne overnight will inevitably lead to conflicts, he warned.

"At night, they're looking for something to do. There's a likelihood of them going off to various locations and disturbing the wildlife."

Worse, he said, would be the precedent of allowing major new development in a relatively untouched area, despite a 2007 Parks Canada policy forbidding new overnight accommodation outside parks communities.

"If you can do it there, in a very pristine area with significant wildlife resources at risk, then what's to prevent someone else to argue at another park that (their proposal) is no worse than the Maligne Lake approval?"

Nor does Lopoukhine believe hotels would do much to expand the reach of the parks.

"What we're looking for is an opportunity for people to experience nature, not a high-end hotel room."

The letter quotes a recent survey that found 99 per cent of those asked were already satisfied with their visit to Maligne Lake.

Parks Canada has held public hearings on the proposal, which is highly controversial in the nearby town of Jasper.

A report the agency issued last month suggested it is at least receptive to the idea.

"At a very preliminary level, and subject to further analysis, redeveloping an existing lodge to include overnight accommodations would not be expected to raise important concerns for impairing ecological integrity," says the report.

"Maligne Tours' proposal is part of their overall experiential package that is conceptually aligned with the intentions in the park management plan to enhance visitor experience opportunities in Jasper National Park and the Maligne Valley in particular."

Neither Parks Canada nor Maligne Tours was available to answer questions.

Parks Canada is expected to make a decision soon. Any development would be subject to an environmental assessment.