PipeProwler Notable Event

Planned pigging on Columbia Gulf's reversed Mainline 200

Up to ~495 MDth/d of southbound Appalachian takeaway off for 8 days; EGS basis softens, HH effect marginal.

· · 1 min read

PipeProwler — severity-graded notable pipeline event with lineage from raw notice to API

Planned pigging on Columbia Gulf's reversed Mainline 200 cuts up to ~495 MDth/d of southbound Appalachian takeaway, May 30 through June 6. Eastern Gas South basis softens as supply backs up behind the constraint at Leach; Gulf and Henry Hub effects are marginal.

Event details

  • Pipeline / operator: Columbia Gulf Transmission (TC Energy)
  • Event type: Planned maintenance (pigging), takeaway constraint
  • Severity grade: Sev 4
  • Affected capacity: 295–495 MDth/d reduction (13–21% of 2,344,656 Dth/d design; reduced setting 1,850–2,050 MDth/d)
  • Duration: 8 days; effective May 30 through June 6, 2026
  • Corridor / hub linkage: Columbia Gulf Mainline 200 StanSEG (reversed, "Net Backhaul"): Appalachian receipts at Leach KY → Stanton CS → southbound Gulf / LNG feedgas
  • Operator notice: Columbia Gulf Notice #26022011, posted May 22, 2026 at 15:38 ET (19:38 UTC)
  • First detected: 2026-05-22 15:38 ET

Tags: columbia-gulf-mainline-200 · eastern-gas-south · planned-maintenance · takeaway-constraint · appalachian-basis

Directional reads describe expected supply/demand implications. Not realized prices. Not trading advice.