Canadian natural gas exports returned to full capacity on Alliance Pipeline over the weekend after no damage was detected during an emergency partial shutdown to inspect a spring flood site in northwest Alberta.
Alliance on Monday reported finding "no integrity concerns" of bending or leaks where rainstorms and melting snow caused hazardous movement of a slope on a riverside stretch of its jumbo pipe, 48 inches in diameter.
An estimated 500 MMcf/d of capacity for liquids-rich gas exports to Chicago from northeastern British Columbia was restored as of Saturday after a four-day interruption, an Alliance statement said Monday.
The pipeline added that work is continuing to shore up the shifting slope along the Wapiti River, in remote countryside near the Alberta-BC boundary west of the regional industry capital of Grande Prairie.
The emergency gas traffic reduction affected about 30% of Alliance capacity for 1.6 Bcf/d in Canadian exports. After crossing into the United States, the flow grows by receiving American production from the Williston Basin via a tributary pipeline, the Tioga Lateral in North Dakota.
Alliance is currently canvassing Canadian industry support for a potential 30% increase in exports on its 3,848-kilometer (2,291-mile) route. Up to 500 MMcf/d of capacity could be gained by low-cost compressor additions that would cause no service interruptions, the offer says.
The 18-year-old Alliance system's capacity has stayed fully booked after expanding its service options prior to expiry of its initial 1999 package of 15-year transportation contracts. Production of liquids-rich gas that the line specializes in carrying is forecast to grow steadily from northeastern BC and northwestern Alberta shale deposits, led by the Montney formation.