Williams and TransCanada Propose New Natural Gas Pipeline for Western U.S.

TULSA, OKLAHOMA--(Marketwire - March 13, 2008) - Williams (NYSE:WMB) and TransCanada Corporation (TSX:TRP) (NYSE:TRP) are evaluating the joint development of Sunstone Pipeline, a major new natural gas transmission pipeline that would offer producers and end-users a cost-effective way to move natural gas supply from the Rockies to markets in the western United States.

The proposed Sunstone Pipeline is a 618-mile, 42-inch-diameter pipeline with capacity of up to 1.2 billion cubic feet per day. The project, which is proposed for service in 2011, would involve constructing a new pipeline substantially parallel to the existing Williams Northwest Pipeline system between the Opal Hub in Wyoming and Stanfield, Ore. Williams' Northwest system interconnects at Stanfield with TransCanada's Gas Transmission Northwest (GTN) pipeline system.

The project provides the option to deliver gas to markets served by the Northwest and GTN pipeline systems. Sunstone's open season will commence March 17 and run through April 30, 2008. GTN will hold an additional open season to offer existing capacity available on its pipeline system between Stanfield and GTN's terminus near Malin, Ore., near California's northern border.

Sunstone offers significant benefits for natural gas producers and consumers:

- Broad access to markets throughout the Pacific Northwest, northern Nevada and northern California;

- Enhanced supply diversity for western markets through increased access to Rocky Mountain supplies;

- Construction of fewer miles of pipeline along existing utility corridors, including segments of Northwest's existing pipeline system;

- Favorable rates due to efficiencies from existing infrastructure and operations along the route;

- Both companies have knowledge of the environment and established relationships with neighboring stakeholders, and Williams has recent construction experience along the pipeline corridor.

"The proposed Sunstone Pipeline project is designed to ensure that our customers have access to abundant and diverse natural gas supplies in the region," said Phil Wright, president of Williams' gas pipeline business. "We have been reliably delivering natural gas to the Pacific Northwest for more than 50 years and have established long-standing relationships with the communities along our pipeline corridor."

"Sunstone offers customers in the West excellent access to markets and supply," said Hal Kvisle, president and chief executive officer of TransCanada. "Sunstone and GTN provide efficient, continued access to Western Canada Sedimentary Basin gas supply in addition to new access to growing Rocky Mountain production. The combination of new and existing infrastructure provides benefits to markets across California, Nevada and the Pacific Northwest."

"Natural gas is a key resource for the future of our region," said Kimberly Harris, executive vice president and chief resource officer for Puget Sound Energy. "Our customers would benefit from enhanced access to diverse supplies of natural gas that could be provided by projects like the Sunstone Pipeline."

About Williams

Williams, through its subsidiaries, finds, produces, gathers, processes and transports natural gas. Williams' operations are concentrated in the Pacific Northwest, Rocky Mountains, Gulf Coast, and Eastern Seaboard. More information is available at http://www.williams.com. Go to http://www.b2i.us/irpass.asp?BzID=630&to=ea&s=0 to join our e-mail list.

About TransCanada

With more than 50 years experience, TransCanada is a leader in the responsible development and reliable operation of North American energy infrastructure including natural gas pipelines, power generation, gas storage facilities, and projects related to oil pipelines and LNG facilities. TransCanada's network of wholly owned pipelines extends more than 59,000 kilometres (36,500 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 355 billion cubic feet of storage capacity. A growing independent power producer, TransCanada owns, or has interests in, approximately 7,700 megawatts of power generation in Canada and the United States. TransCanada's common shares trade on the Toronto and New York stock exchanges under the symbol TRP.

FORWARD-LOOKING INFORMATION

Williams:

Portions of this document may constitute "forward-looking statements" as defined by federal law. Although the companies believe any such statements are based on reasonable assumptions, there is no assurance that actual outcomes will not be materially different. Any such statements are made in reliance on the "safe harbor" protections provided under the Private Securities Reform Act of 1995. Additional information about issues that could lead to material changes in performance is contained in the company's annual reports filed with the Securities and Exchange Commission.

TransCanada:

This news release may contain certain information that is forward looking and is subject to important risks and uncertainties. The words "anticipate", "expect", "may", "should", "estimate", "project", "outlook", "forecast" or other similar words are used to identify such forward looking information. All forward-looking statements are based on TransCanada's beliefs and assumptions based on information available at the time such statements were made. 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, changes in environmental and other laws and regulations, competitive factors in the pipeline and energy industry sectors, construction and completion of capital projects, access to capital markets, interest and currency exchange rates, technological developments and the current economic conditions in North America. By its nature, such 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 other expectations expressed. For additional information on these and other factors, see the reports filed by TransCanada with Canadian securities regulators and with the U.S. Securities and Exchange Commission. Readers are cautioned not to 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 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.
 

TransCanada
Media Inquiries
Shela Shapiro/Cecily Dobson
(403) 920-7859 or (800) 608-7859
or
Williams
Michele Swaner
(801) 584-7048
or
Investor & Analyst Inquiries
David Moneta/Myles Dougan/Terry Hook
(403) 920-7911 or (800) 361-6522
Website: www.transcanada.com
or
Williams
Richard George
(918) 573-3679