AltaGas' Mclymont Creek and Volcano Creek Impact Benefit Agreements Ratified by the Tahltan First Nation

CALGARY, ALBERTA--(Marketwire - Sept. 15, 2011) - AltaGas Ltd. (AltaGas) (TSX:ALA) today announced that it has received notification from the Tahltan Central Council that the Tahltan membership voted in favour of the Impact Benefit Agreements (IBAs) for its McLymont Creek and Volcano Creek run-of-river hydroelectric projects. These projects are located near AltaGas' 195-MW Forrest Kerr project, currently under construction, approximately 1,000 km north of Vancouver, BC. AltaGas expects the Forrest Kerr project to come into service in 2014, followed by McLymont Creek in 2015 and Volcano Creek in 2016. Collectively the projects are known as the Northwest Projects.

"The positive outcome of the ratification vote on the IBAs related to these projects reflects our strong working relationship with the Tahltan Nation that brings significant employment and business opportunities and economic participation in our Northwest Projects." said David Cornhill, Chairman and Chief Executive Officer of AltaGas. "The IBAs are an important step in the continued development of AltaGas' Northwest Projects and of our power business. Our Northwest Projects will provide the people of British Columbia with clean and reliable power while increasing value to our shareholders with stable, long-term cash flow."

"This is an exciting and pivotal time for our Nation. Our leadership team has worked hard to negotiate agreements in the best interests of our people and our Nation and we are pleased the relationship built between AltaGas and the Tahltan Nation has resulted in the majority of Tahltans ratifying the Impact Benefit Agreements for the McLymont Creek and Volcano Creek projects," said Annita McPhee, Chair of the Tahltan Central Council. "These agreements will enable us to continue to foster social, cultural, economic and environmental health within our community."

The Northwest Projects are to be constructed wholly within Tahltan Nation traditional territory and are expected to cost approximately $1 billion. Once completed, the projects will provide enough electricity for approximately 95,000 homes in British Columbia and will offset more than 780,000 tonnes of greenhouse gas equivalents annually. The projects will deliver electricity to the terminus point of the previously announced 287-kV Northwest Transmission Line (NTL), near Bob Quinn, BC. BC Hydro is constructing the NTL.

AltaGas is an energy infrastructure business with a focus on natural gas, power and regulated utilities. AltaGas creates value by acquiring, growing and optimizing its energy infrastructure, including a focus on renewable energy sources. For more information visit: www.altagas.ca.

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