Rockies Express Pipeline LLC (REX) selected contracting services company Quanta Services Inc. to provide turnkey engineering, procurement and construction services for its REX Zone Three capacity enhancement project, Quanta said Aug. 31.

QPS Engineering and Price Gregory International, subsidiaries of Quanta, will work on the project, which includes installing three new compressor stations and upgrading two existing compressor stations.

REX is the only pipeline linking the Rocky Mountain and Appalachian supply basins to the Midwest and Gulf Coast markets, moving natural gas from the Rockies and Utica and Marcellus shales.

Engineering and other front-end services have begun. Quanta said construction is scheduled to begin in second-quarter 2016, or when REX receives the required regulatory approvals. Completion is scheduled for fourth-quarter 2016. The new and upgraded facilities could create up to 800,000 dekatherms per day of additional natural gas takeaway capacity from the Appalachian Basin to Midwestern and other gas markets.

Quanta Services Inc. is based in Houston.