WASHINGTON - Canada appealed to Secretary of State Condoleezza Rice on Thursday to put a hold on a drainage project in North Dakota that environmentalists fear will take polluted water and alien species of wildlife across the border into Manitoba province.

Time is running out because the $28 million project is to be opened next month.

Frank McKenna, the Canadian ambassador in Washington, wrote Thursday in the New York Times that the Devils Lake project would dump pollutants into the Sheyenne and Red rivers that would damage not only Canada but downstream towns in North Dakota and Minnesota.

"Moreover, species of fish, plants, parasites and viruses previously confined in Devils Lake, in some cases for millenniums, will spill out" into the two rivers, McKenna wrote. "There they could kill the native plants and fish of the larger ecosystem."

On the Canadian side, it threatens worrisome consequences for Lake Winnipeg, the largest freshwater fishery in North America, he wrote.

A week ago, North Dakota Gov. John Hoeven ruled out asking for a scientific study by the International Joint Commission, a century-old Canadian-U.S. agreement designed to settle water disputes. Hoeven dismissed the idea of a review proposal in a telephone talk with Reg Alcock, president of the Canadian Treasury Board.

As secretary of state, Rice has the ultimate decision whether to invoke the international agreement and take the project to the commission.