CANADIAN MAINLINE  TransCanada's 100 per cent owned, 14,957 km natural gas transmission system in Canada extends from the Alberta/Saskatchewan border east to the Québec/Vermont border and connects with other natural gas pipelines in Canada and the U.S.

ALBERTA SYSTEM  TransCanada's 100 per cent owned natural gas transmission system in Alberta gathers natural gas for use within the province and delivers it to provincial boundary points for connection with the Canadian Mainline, BC System, Foothills and other pipelines. The 23,498 km system is one of the largest carriers of natural gas in North America.

GAS TRANSMISSION NORTHWEST SYSTEM  TransCanada's 100 per cent owned natural gas transmission system extends 2,174 km and links the BC System and Foothills with Pacific Gas and Electric Company's California Gas Transmission System, with Williams' Northwest Pipeline in Washington and Oregon, and with Tuscarora.

FOOTHILLS  TransCanada's 100 per cent owned, 1,040 km natural gas transmission system in western Canada carries natural gas for export from central Alberta to the U.S. border to serve markets in the U.S. Midwest, Pacific Northwest, California and Nevada.

BC SYSTEM  TransCanada's 100 per cent owned natural gas transmission system extends 201 km from Alberta's western border through British Columbia (B.C.) to connect with the Gas Transmission Northwest System at the U.S. border, serving markets in B.C. as well as the Pacific Northwest, California and Nevada.

NORTH BAJA  TransCanada's 100 per cent owned natural gas transmission system extends 129 km from southwestern Arizona at Ehrenberg to a point near Ogilby, California on the California/Mexico border and connects with the Gasoducto Bajanorte pipeline system in Mexico.

VENTURES LP  Ventures LP, which is 100 per cent owned by TransCanada, owns a 121 km pipeline and related facilities which supply natural gas to the oil sands region of northern Alberta, and a 27 km pipeline which supplies natural gas to a petrochemical complex at Joffre, Alberta.

TAMAZUNCHALE  TransCanada's 100 per cent owned, 130 km natural gas pipeline in east central Mexico extends from the facilities of Pemex Gas near Naranjos, Veracruz to an electricity generation station near Tamazunchale, San Luis Potosi. This pipeline went into service on December 1, 2006.

ANR  On February 22, 2007, TransCanada acquired 100 per cent of the ANR natural gas transmission system which extends approximately 17,000 km from producing fields in Louisiana, Oklahoma, Texas and the Gulf of Mexico to markets in Wisconsin, Michigan, Illinois, Ohio and Indiana. This pipeline also connects with other pipelines to give access to supply from western Canada, the Rocky Mountain region and a variety of markets in the midwestern and northeastern U.S. ANR also owns and operates underground natural gas storage facilities in Michigan with a total capacity of approximately 230 Bcf.

TUSCARORA  Tuscarora is owned or controlled 99 per cent by PipeLines LP and is a 491 km pipeline system transporting natural gas from the Gas Transmission Northwest System at Malin, Oregon to Wadsworth, Nevada with delivery points in northeastern California and northwestern Nevada. TransCanada operates Tuscarora and, at February 22, 2007, effectively owns or controls an aggregate 32.8 per cent interest in Tuscarora, of which 31.8 per cent is held indirectly through TransCanada's 32.1 per cent ownership interest in PipeLines LP and the remaining one percent is owned directly.

NORTHERN BORDER  Northern Border is 50 per cent owned by PipeLines LP and is a 2,250 km natural gas pipeline system which serves the U.S. Midwest from a connection with Foothills near Monchy, Saskatchewan. In April 2007, TransCanada expects to become the operator of Northern Border. At February 22, 2007, the Company effectively owns approximately 16.1 per cent of Northern Border through its 32.1 per cent ownership interest in PipeLines LP.

GREAT LAKES  Great Lakes is a 3,404 km pipeline system that connects with the Canadian Mainline at Emerson, Manitoba and serves markets in central Canada and the midwestern U.S. Effective February 22, 2007, TransCanada owns 53.55 per cent of Great Lakes and PipeLines LP owns the remaining 46.45 per cent. TransCanada's effective ownership of Great Lakes is 68.5 per cent of which 14.9 per cent is held indirectly through its 32.1 per cent ownership in PipeLines LP. TransCanada is the operator of Great Lakes.

IROQUOIS  Iroquois connects with the Canadian Mainline near Waddington, New York and delivers natural gas to customers in the northeastern U.S. TransCanada has a 44.5 per cent ownership interest in this 666 km pipeline system.

TQM  TQM is a 572 km natural gas pipeline system which connects with the Canadian Mainline and transports natural gas from Montréal to Québec City and to the Portland system. TransCanada holds a 50 per cent ownership interest in TQM and is the operator.

PORTLAND  Portland is a 474 km pipeline that connects with TQM near East Hereford, Québec and delivers natural gas to customers in the northeastern U.S. TransCanada has a 61.7 per cent ownership interest in Portland and operates this pipeline.

TRANSGAS  TransGas is a 344 km natural gas pipeline system which runs from Mariquita in the central region of Colombia to Cali in the southwest of Colombia. TransCanada holds a 46.5 per cent ownership interest in this pipeline.

GAS PACIFICO  Gas Pacifico is a 540 km natural gas pipeline extending from Loma de la Lata, Argentina to Concepción, Chile. TransCanada holds a 30 per cent ownership interest in Gas Pacifico.

INNERGY  INNERGY is an industrial natural gas marketing company based in Concepción, Chile that markets natural gas transported on Gas Pacifico. TransCanada holds a 30 per cent ownership interest in INNERGY.