Williams Partners has filed an application with the Federal Energy Regulatory Commission (FERC) to expand its Transco natural gas pipeline by 225,000 dekatherms per day to serve markets in the southeastern US.

New service from the Mid-South Expansion project would be available in two phases, subject to FERC approval.

Phase 1 would increase capacity by 95,000 dekatherms per day by the fall of 2012, while Phase II would increase capacity by 130,000 dekatherms per day by the summer of 2013.

The Mid-South Expansion project is designed to transport clean-burning natural gas from Transco’s Station 85 pool to new and existing power generation and municipal facilities in the southeast.

The Mid-South Expansion project will require construction of approximately 23 miles of new pipeline, a new 32,000 horsepower compressor facility in Dallas County, Alabama, and upgrades to existing compressor facilities in Alabama, Georgia, South Carolina and North Carolina.

Williams estimates that the project facilities will cost approximately $219m.

In March, Williams notified the FERC to initiate a pre-application environmental review of the expansion project.

Since that time, Williams has solicited input from citizens, governmental entities and other interested parties to collect feedback and answer questions about the proposal.