Williams Partners to Significantly Increase Transco Leidy Line Capacity by 2015; Defers Balance of Proposed Atlantic Access

Expansion will serve local gas distribution companies and the growing power-generation market along the Eastern Seaboard and in the Southeast Williams Partners L.P.

today announced that it has received interest from shippers to expand its existing Transco pipeline Leidy Line in northern Pennsylvania by up to 800,000 dekatherms of natural gas per day by late 2015. Williams

owns approximately 68 percent of Williams Partners, including the general-partner interest. The Leidy Southeast expansion project is being designed to serve the growing needs of local gas distribution companies and electric power generators along the Atlantic Seaboard and throughout the southeastern United States. The company is currently finalizing shipper agreements and expects to initiate pre-filing with the Federal Energy Regulatory Commission (FERC) in early 2013. The final scope and cost of the project will be determined by the results of shipper negotiations.