TransCanada Purchases Williams' Interest in Northern Border Partners, L.P.

CALGARY, Alberta – August 16, 2002 – (TSX: TRP) (NYSE: TRP) – TransCanada PipeLines Limited today announced it has completed the acquisition of a subsidiary of The Williams Companies Inc., for US$12 million. The acquisition provides TransCanada with a general partnership interest in Northern Border Partners, L.P. (NYSE: NBP), a publicly held U.S. limited partnership, and increases TransCanada’s indirect ownership interest in Northern Border Pipeline Company.

“TransCanada considers Northern Border Pipeline to be one of the preferred routes to move gas from the North to market in the future,” said Hal Kvisle, TransCanada's chief executive officer. “While the acquisition is not of a large scale, it provides TransCanada with a strategic opportunity to participate in the management of Northern Border Partners.” The acquisition will also allow TransCanada to participate in Northern Border Partners’ cash distributions.

As a result of the acquisition, TransCanada effectively owns 0.35 per cent of the aggregate two per cent general partnership interest in Northern Border Partners. As a result, TransCanada is entitled to a 17.5 per cent vote on the partnership policy committee of Northern Border Partners. Two affiliates of Enron Corp. own the remaining general partnership interests in Northern Border Partners and are entitled to an aggregate 82.5 per cent vote on the partnership policy committee. The limited partnership interests in Northern Border Partners are held primarily by the public.

Northern Border Partners owns 70 per cent of Northern Border Pipeline. The other 30 per cent of Northern Border Pipeline is owned by TC PipeLines, LP (Nasdaq: TCLP), whose general partner is a wholly owned subsidiary of TransCanada. The acquisition does not impact TransCanada’s 33.41 per cent ownership interest in TC PipeLines or TC PipeLines’ ownership interest in Northern Border Pipeline. TransCanada indirectly owns approximately 10 per cent of Northern Border Pipeline through its interest in TC PipeLines. TransCanada and TC PipeLines now effectively designate two members of the four-member management committee of Northern Border Pipeline and control an aggregate 42.25 per cent of the voting power on that committee.

Northern Border Pipeline is a 2,010-kilometre (1,249-mile) interstate pipeline system that transports natural gas from the Montana-Saskatchewan border to markets in the midwestern United States.

In addition to its interest in Northern Border Pipeline, Northern Border Partners owns the 565-kilometre (350-mile) Midwestern Gas Transmission system, which stretches from Portland, Tenn., to Joliet, Ill. Northern Border Partners also has gathering systems and processing plants in the Powder River, Wind River, and Williston Basins in the U.S.; owns and operates processing plants and gathering pipelines in Alberta, Canada; and transports coal-water slurry via a pipeline in the southwestern U.S.

TransCanada is a leading North American energy company. It is focused on natural gas transmission and power services with employees who are expert in these businesses. The company’s network of approximately 38,000 kilometres of pipeline transports the majority of western Canada’s natural gas production to the fastest growing markets in Canada and the United States. TransCanada owns, controls, manages or is constructing a total of approximately 2,250 megawatts of power -- an amount of power that can meet the needs of more than two million average households. The company’s common shares trade under the symbol TRP on the Toronto and New York stock exchanges. Visit us on the internet at for more information.

Forward looking Information

Certain information in this news release is forward-looking and is subject to important risks and uncertainties. The results or events predicted in this information may differ from actual results or events. Factors which could cause actual results or events to differ materially from current expectations include, among other things, the ability of TransCanada to successfully implement its strategic initiatives and whether such strategic initiatives will yield the expected benefits, the availability and price of energy commodities, regulatory decisions, competitive factors in the pipeline and power industry sectors, and the current economic conditions in North America. For additional information on these and other factors, see the reports filed by TransCanada with Canadian securities regulators and with the United States Securities and Exchange Commission. TransCanada disclaims any intention or obligation to update or revise any forward-looking statements, whether as a result of new information, future events or otherwise.

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