- Source: Joliet, Ill.
- Destination: Green Bay, Wisconsin
- Ownership: Northern Border Partners (Oneok)
- Website: http://www.oneokpartners.com/
- Length: kilometres (252 miles)
- Capacity: per day
- Status: Operating
- Guardian Pipeline is a 143-mile interstate natural gas pipeline system that began service in December 2002. It has the capacity to transport 750,000 dekatherms per day (Dth/d) of natural gas from the Joliet Natural Gas Hub Illinois, to Ixonia, Wisc.
- It was expanded to 252 miles to serve Green Bay in 2006
- 2002 - Guardian Gas Pipeline entered service
- 2006 - Guardian announced that it will expand and extend the existing pipeline approximately 106 miles from Ixonia to the Green Bay area
- 2006 - Northern Border Partners acquired an additional 66%, becoming sole owner
- 2009 - Pipeline Expansion and Extension Project completed
- EIA Natural Gas Pipeline Projects 2000-2009
- Northern Border Partners, L.P. To Purchase Remaining Interests in Guardian Pipeline, L.L.C.
- Northern Border Partners, L.P. Completes Purchase of Interests in Guardian Pipeline, L.L.C.