Nearly a year after Boardwalk Pipelines approved the Kosciusko Junction Pipeline project, the U.S. Federal Energy Regulatory Commission (FERC) has formally initiated its environmental review for the proposed 111-mile natural gas expansion by Boardwalk subsidiaries Gulf South Pipeline Co. and Texas Gas Transmission.
FERC issued a Notice of Intent to Prepare an Environmental Impact Statement (EIS) on November 14, 2025 (Docket No. CP25-547-000), marking the project’s transition from corporate approval and commercial commitments to the federal regulatory phase. The notice, published for the first time in public filings, details pipeline specifications, routing, compressor horsepower, and a review schedule extending through October 2026.
The Kosciusko Junction project includes approximately 111.5 miles of new 36-inch-diameter pipeline and nearly 93,500 horsepower of additional compression across multiple facilities in Mississippi. Gulf South plans to construct and operate two new segments: a 103.4-mile Kosciusko Junction mainline crossing Holmes, Attala, Leake, Newton, and Jasper counties, and an 8.1-mile Columbia Gulf Lateral in Clarke County to interconnect with Columbia Gulf Transmission and other existing systems.
The project also proposes three new compressor stations—a 51,554-hp Kosciusko Station, a 20,952-hp Holmes Station, and upgrades at the Isola Compressor Station adding two 20,993-hp units—along with four new meter stations and mainline valve assemblies. Together, these facilities would provide up to 1.175 billion cubic feet per day of incremental firm transportation capacity.
Under the filings, Texas Gas Transmission will abandon and transfer its 98-mile Greenville Lateral to Gulf South, which will replace it with two new 36-inch segments totaling 111.5 miles and associated compression and metering infrastructure. The design includes tie-ins to Destin Pipeline, Southern Natural Gas, and Columbia Gulf Transmission, improving