Government authorities began an emergency airlift Wednesday to move more than 1,000 residents from an impoverished Indian reserve where drinking water was contaminated by raw sewage.

The abrupt evacuation order, after months of wrangling between government agencies, highlighted the poor conditions on Indian reserves and questions about Canada's sewage discharge practices, which one environmental group termed a "national disgrace."

Most remote northern towns -- including reserves of Indians, known as First Nations here -- dump sewage directly into lakes or rivers, according to a series of reports by the Sierra Legal Defense Fund, based in Vancouver. Even larger cities, including Montreal, Halifax and Victoria, dump raw sewage into the seas.

The evacuation was being carried out at Kashechewan, a Cree Indian reserve on the western shore of James Bay, about 600 miles north of Toronto.

The water intake of the reserve, a riverbank community of about 1,900, is downstream from a sewage outlet. Local Cree leaders have long complained about the water quality, but various federal agencies have argued over how to deal with it.

Lindsay MacMillan, a visiting physician in the town of Moose Factory, which has the closest hospital, went to the reserve by helicopter with another doctor on Saturday after hearing complaints of a spike in deadly E. coli bacteria followed by overchlorination of the water.

"I was shocked," she said by telephone Wednesday from Moose Factory. "It was like a developing country. It was appalling to me that we were in Canada." MacMillan said she visited 40 homes, and in nearly every one she found children with skin infections aggravated by poor hygiene, "dirty living conditions" and the intensely chlorinated water.

Ontario's provincial premier, Dalton McGuinty, ordered the air evacuation, although the native reserves are under federal jurisdiction, he said.

"We don't have time to wait," McGuinty told reporters in Toronto. "These are unacceptable, deplorable conditions."

Safe drinking water is only one difficulty for First Nations reserves, long plagued by unemployment, alcoholism, poor nutrition and associated social problems. MacMillan said she found families crowded into homes and living in "extreme poverty."

But water quality has been a particularly sensitive public issue since May 2000, when seven people died from E. coli that had contaminated the water supply in rural Walkerton, Ontario. A formal inquiry into that incident noted that "the water provided on many First Nation reserves is some of the poorest-quality water in the province."

More than 50 reserves in Ontario are now under orders to boil drinking water. "Everyone should be able to turn a tap on and get water and not get sick from it," said Ginette Albert, an official in Ontario's Natural Resources Ministry, which is coordinating the evacuation of Kashechewan.

John Werring, a senior scientist at the Sierra Legal Defense Fund, said Canada had not set national standards for sewage treatment, as most other developed countries have. Kashechewan "is not an isolated situation," he said. Native reserves often lack money, expertise and political clout, and the evacuation is "symptomatic of a much greater problem, which is how the first nations are being treated with substandard sewage treatment and drinking water."

Because of the accumulation of problems in Kashechewan, provincial officials said they were unsure whether evacuated residents would return. The residents are being flown to several northern communities that can house them "on a semi-permanent basis," a spokesman for the Ontario Emergency Management Agency said.

Local Indian leaders declined to speak by telephone Wednesday. But a woman who answered the phone in the town's general store said, "They are taking the elderly and the most sick today." The woman, who declined to give her name, added, "This is a good first step."