With a severe drought emptying reservoirs from Montana to Maryland, and California threatening to drain the last drop from the Colorado River, it may seem like an opportune moment for the United States to approach its friendly northern neighbor for some of that cool, clean Canadian water.

With 20 percent of the world's supply of fresh water, Canada has more water than it could ever need. Even after discounting for icebergs, that's still four times the per capita renewable water reserve of the United States.

But don't count on Canadians sharing any of it. For nothing, it seems, stirs Canada's nationalistic passions more than the prospect of exporting its precious national fluid. Though the country's economy was built on the export of its natural riches, this one's off-limits -- even though it is readily renewable.

"The Americans are coming after our water," Nelson Riis, a member of Parliament from British Columbia, declared earlier this year in urging passage of a resolution calling for an immediate government ban on bulk water exports. The nonbinding measure passed unanimously; no ban resulted, but the vote helped spur the government on the issue.

U.S. officials say they are aware of Canadian sensitivities regarding water and have not approached the Canadian government about help with easing drought conditions.

But American companies have sought to purchase Canadian water in the past -- most recently invoking the North American Free Trade Agreement -- and Canada has resisted. Foreign Minister Lloyd Axworthy recently told the BBC that a joint U.S.-Canada commission has made "very clear this is not a trade-related matter, it's an environmental matter."

Likewise, Canada has moved to pull the plug on an effort by businessmen here in Grand Le Pierre to quench thirsts abroad and solve the unemployment problem at home by selling water from nearby Gisborne Lake. As the federal government tries to persuade all of its provinces to ban bulk exports of water, water-rich Newfoundland could provide the first test of Canadian hydro-nationalism.

Tom Osborne, a leading Conservative member of Newfoundland's provincial legislature, predicts that in the coming era of global warming, Canada could become the Saudi Arabia of H 2 O. "Water is the commodity of the next century, and those who possess it and control it could be in a position to control the world's economy," said Osborne. "Why should we give away this precious resource now?"

This fall, the Canadian government plans to push through legislation banning bulk water removal from all boundary waters over which it has jurisdiction. On Wednesday, such a ban won the endorsement of the U.S.-Canada joint commission charged with overseeing the waters on their common border, including the Great Lakes. In a lengthy interim report, the commission concluded that uncertainty about global warming and the future demands about water require a "cautionary approach" to all bulk water removals.

At the same time, Ottawa is leaning hard on the 13 provinces and territories, which control most of the country's fresh water, to institute an export ban for water within their borders. Ontario and British Colombia have already adopted export bans -- each after deals by private firms to export water ignited a public outcry.

Here on the southern coast of Newfoundland, a local entrepreneur proposes to fill a supertanker every two weeks with a portion of the water that normally flows out of crystal clear Gisborne Lake, five miles inland. Each tanker would carry about 130 million gallons of water, so shipments could provide enough water for a reasonably conservation-minded city of 175,000.

It is estimated that the $24 million project would yield $20 million in royalties and taxes for the perennially cash-strapped Newfoundland government and, with an accompanying bottling plant, would create 150 jobs in Grand Le Pierre, a tiny coastal community devastated by the closure of the North Atlantic cod fishery seven years ago.

"We're going right down the drain now because all the young people are moving away to find work," said George Fizzard, 69, the town's mayor, who says the population has dropped from 450 to 350 in the last few years as the unemployment rate reached nearly 70 percent. "As far as we are concerned, the water project would be a godsend. It would employ the whole town -- and then some."

With 20 percent of its surface area covered with lakes, Newfoundland set out three years ago to encourage just such projects under strict environmental guidelines and a fixed schedule of royalties. A review conducted over the past year has found that the proposed project would cause little if any disruption to the environment, diverting about 15 percent of the 47 billion gallons that flow into and out of Gisborne Lake in a typical year.

Jerry White, a building contractor and real estate developer from Gander who is behind the project, won't say where the tankers full of water will be going each week, or what the water will be used for, although he claims to have a foreign buyer lined up. Within five years, he envisions turning his bottling company into the "Evian of North America," turning out 50 million bottles a year of sparkling Newfoundland water.

The water, he says, will hardly be missed. "The way I like to explain it," he said, "is that by the time the tanker has left the 200-mile [territorial] limit, the level of the lake will be back to where it was before [the tanker] was filled up. I don't see what the big problem is in that."

Nor did provincial environmental officials -- until the federal government stepped in, pressuring Newfoundland Premier Brian Tobin to impose a moratorium on water exports until a new national policy could be put in place. With Newfoundland's economy still heavily dependent on transfer payments from the federal government, and with Tobin angling to succeed Prime Minister Jean Chretien, provincial officials last week indicated they would fall in line.

Canada's concerns about water diversions date from the 19th century, when Chicago first began taking water from Lake Michigan for use in flushing its sewage into the Illinois River. Over the years, there have been numerous schemes to make rivers flow in different directions and to tow icebergs down from the Arctic.

Perhaps the most ambitious project was proposed in 1959 by Tom Kierans, a Newfoundland mining engineer. His ambitious -- and, some said, ridiculous -- proposal was to use nuclear power and enormous dikes to divert fresh water from Hudson Bay to the Great Lakes and on to the Missouri and Colorado rivers.

Kierans's $100 billion Grand Canal project attracted financial backing from a number of big engineering firms and politicians on both sides of the border. But it also attracted the noisy opposition of Canadian environmentalists and nationalists.

Today, the Canadian government takes pains to disassociate itself from the anti-American tone of the debate over water exports.

Rather, Axworthy, the foreign minister, argues that the export ban is driven by a recognition that fresh water is "too precious" to be treated like other commodities, as well as concerns that removing large amounts of water from any watershed can have "untold and unpredictable consequences" for the environment.

Those rationales, however, ring hollow to some experts.

John Crosbie, a former federal minister of just about everything and the gray eminence of Newfoundland politics, said: "This isn't about reason or logic. It's about the constant fear and jealousy that Canadians have of the United States. There's this innate suspicion that we'll go too far and we won't be able to turn off the spigot when we need the water for ourselves. It's all nonsense."