Williams Cos. (WMB) informed the Federal Energy Regulatory Commission on Feb. 26 that work on an expansion of the MountainWest Overthrust Pipeline has started.

Williams’ Westbound Compression Expansion Project will increase capacity to Opal, a regional natural gas hub in Wyoming. The 325 MMcf/d expansion will bring additional capacity to meet growing demand in the region and the West Coast, according to the company.

The work consists primarily of upgrading compressor stations along the route with more horsepower. Williams expects the expansion to be in-service by the end of 2025. The line is one of the few options to deliver natural gas to the West Coast.