CALGARY, ALBERTA--(Marketwire - June 5, 2011) - TransCanada Corporation (TSX:TRP) (NYSE:TRP) (TransCanada) today announced the Keystone Pipeline system has resumed transporting crude oil. This follows Saturday's approval of TransCanada's re-start plan by the U.S. Pipelines and Hazardous Materials Safety Administration (PHMSA). TransCanada voluntarily shut down the pipeline May 29 following an above-ground incident at a pump station in Kansas involving less than 10 barrels of oil.

In a letter to TransCanada, PHMSA stated, 'Based on a review of the information submitted, the restart plan is approved.'

TransCanada employees worked around the clock, taking the necessary actions needed to allow the pipeline to resume the safe and reliable transportation of crude oil. Keystone will be monitored closely in the coming days to ensure it is functioning appropriately.

"TransCanada takes all incidents very seriously," said Russ Girling, TransCanada's president and chief executive officer. "Almost all of the oil releases over the last 11 months on Keystone have been minor - averaging just five to 10 gallons of oil. The vast majority of that oil was confined to our property and in all cases was cleaned up quickly. None of the incidents involved the pipe in the ground - the integrity of Keystone is sound."

In each incident, TransCanada's monitoring system functioned as designed and detected a pressure drop on the pipeline quickly. The company reacted by remotely closing valves in the pipeline, shutting down the entire system within minutes, stopping the flow of oil. The company's safety processes worked as they were planned to.

TransCanada has made improvements to the system by modifying or replacing all appropriate fittings at pump stations in the U.S. and Canada. At certain pump stations, TransCanada had teams on-site to support a safe re-start. Additional tests along the entire length of the pipeline have also been performed to ensure its integrity.

Flows will be gradually ramped up in the coming days and TransCanada will be able to move all volumes nominated by our customers for the month of June.

With more than 60 years experience, TransCanada is a leader in the responsible development and reliable operation of North American energy infrastructure including natural gas and oil pipelines, power generation and gas storage facilities. TransCanada's network of wholly owned natural gas pipelines extends more than 57,000 kilometres (35,500 miles), tapping into virtually all major gas supply basins in North America. TransCanada is one of the continent's largest providers of gas storage and related services with approximately 380 billion cubic feet of storage capacity. A growing independent power producer, TransCanada owns, or has interests in, over 10,800 megawatts of power generation in Canada and the United States. TransCanada is developing one of North America's largest oil delivery systems. TransCanada's common shares trade on the Toronto and New York stock exchanges under the symbol TRP. For more information visit: www.transcanada.com.

Forward-Looking Information

This news release may contain certain information that is forward looking and is subject to important risks and uncertainties. The words "anticipate," "expect," "believe," "may," "should," "estimate," "project," "outlook," "forecast" or other similar words are used to identify such forward-looking information. Forward-looking statements in this document are intended to provide TransCanada securityholders and potential investors with information regarding TransCanada and its subsidiaries, including management's assessment of TransCanada's and its subsidiaries' future financial and operations plans and outlook. Forward-looking statements in this document may include, among others, statements regarding the anticipated business prospects, projects and financial performance of TransCanada and its subsidiaries, expectations or projections about the future, and strategies and goals for growth and expansion. All forward-looking statements reflect TransCanada's beliefs and assumptions based on information available at the time the statements were made. Actual results or events may differ from those predicted in these forward-looking statements. Factors that could cause actual results or events to differ materially from current expectations include, among others, the ability of TransCanada to successfully implement its strategic initiatives and whether such strategic initiatives will yield the expected benefits, the operating performance of TransCanada's pipeline and energy assets, the availability and price of energy commodities, capacity payments, regulatory processes and decisions, changes in environmental and other laws and regulations, competitive factors in the pipeline and energy sectors, construction and completion of capital projects, labour, equipment and material costs, access to capital markets, interest and currency exchange rates, technological developments and economic conditions in North America. By its nature, forward-looking information is subject to various risks and uncertainties, which could cause TransCanada's actual results and experience to differ materially from the anticipated results or expectations expressed. Additional information on these and other factors is available in the reports filed by TransCanada with Canadian securities regulators and with the U.S. Securities and Exchange Commission (SEC). Readers are cautioned to not place undue reliance on this forward-looking information, which is given as of the date it is expressed in this news release or otherwise, and to not use future-oriented information or financial outlooks for anything other than their intended purpose. TransCanada undertakes no obligation to update publicly or revise any forward-looking information, whether as a result of new information, future events or otherwise, except as required by law.

Contact Information:

TransCanada
Media Enquiries:
Terry Cunha/Shawn Howard
403.920.7859 or 800.608.7859

TransCanada
Analyst Enquiries:
David Moneta/Terry Hook/Lee Evans
403.920.7911 or 800.361.6522
www.transcanada.com