DT Midstream awards capacity on Guardian Pipeline expansion

DT Midstream Inc. closed a binding open season to award expansion capacity on the 260-mile interstate Guardian Pipeline and awarded capacity to five shippers totaling 328,103 Dth/day with a targeted in-service date of Nov. 1, 2028. 

The open season for the expansion closed Sept. 29, 2025. 

The newly awarded capacity, combined with expansion capacity previously awarded in July 2025, totals 536,903 Dth/day of expansion capacity, which amounts to an estimated 40% increase from Guardian’s current 1.3 bcfd capacity.

“The strong interest in this expansion capacity is an indication of the growing demand for natural gas in Wisconsin and the Upper Midwest region where our pipelines are well-positioned,” said David Slater, President and CEO.

The roughly 210 MMcfd expansion, to be completed via a combination of compression and looping, is expected to increase delivery capacity into northern Illinois and Wisconsin markets, the company noted in a September 2025 conference presentation. 

Guardian Pipeline is 100% owned by DT Midstream and is interconnected to DT Midstream’s Midwestern Gas Transmission pipeline and Vector Pipeline and serves key Wisconsin demand centers.