Williams Partners LP said Thursday Transcontinental Gas Pipe Line (Transco) has filed an application with FERC seeking authorization for its Southeastern Trail expansion project, which would open up more capacity to meet rising natural gas demand in Virginia, North Carolina, South Carolina and Georgia.

The project would create 296,375 Dth/d of additional firm transportation capacity on Transco, according to the filing with the Federal Energy Regulatory Commission [CP18-186]. Precedent agreements with utility and local distribution companies have been executed in all four states, with plans to have the expansion done in time for the 2020-2021 winter heating season.

“Southeastern Trail is a critical project that will work to bring key supplies from interconnects in the Mid-Atlantic region to growing demand centers in the Southeastern U.S.,” said Williams COO Michael Dunn. Williams owns about 75% of the pipeline partnership. “This vital project, along with additional expansion opportunities under development, will link low-cost supply to key customers in high-growth markets and continues the expansion of southbound capacity on the Transco pipeline system.”

An open season was held last summer, which resulted in binding precedent agreements with five shippers for all of the capacity, including PSNC Energy, South Carolina Electric & Gas, Virginia Natural Gas and the Georgia cities of Buford and LaGrange.

Southeastern Trail would include 7.7 miles of 42-inch diameter pipeline looping facilities in Virginia, horsepower additions at existing compressor stations in the state, and piping and valve modifications on other existing facilities in South Carolina, Georgia and Louisiana to allow for bi-directional flow.

The project is expected to cost $404.8 million. Williams Partners is targeting a Nov. 1, 2020 in-service date.

Dunn said that by using Transco’s existing corridor for the expansion, the project would have less of an environmental impact and more economical transportation rates for its customers, compared to other greenfield projects serving the same markets.

Natural gas, particularly Appalachian supplies, have found a bigger market in the Southeast in recent years, accounting for a larger share of power generation across the South. Along with additional demand from other sectors, supply has stoked a bevy of market-pull greenfield and expansion pipeline projects to move more gas from the west and north.

Sponsors of the Mountain Valley Pipeline, which is under construction to move 2 Bcf/d of Appalachian gas to the Southeast, announced an expansion project on Wednesday to serve PSNC in North Carolina.