The project will be built by the Williams Partners subsidiary for Washington state energy utility, Puget Sound Energy (PSE).

As part of it, Northwest Pipeline will dismantle an existing 8-inch pipeline and replace it with a 20-inch pipeline within the original right of way. It will also upgrade the North Seattle meter station.

The North Seattle Lateral is used by PSE to supply natural gas to its customers. PSE serves around 800,000 gas customers in six counties in the state.

Williams Partners West operating area senior vice president Walter Bennett said: “Demand for natural gas in the North Seattle region and other major markets continues to grow as customers recognize its value as a clean, affordable and abundant energy source.

“The North Seattle Lateral Upgrade project will add important energy infrastructure necessary to meet the region’s growing demand for natural gas.”

By improving the pipeline infrastructure, Northwest Pipeline expects to expand the delivery capabilities of the North Seattle Lateral by 84,200dth/day.

The construction-related work of the North Seattle Lateral Upgrade project is slated to commence in the second quarter of 2019, subject to receipt of all local, state and federal regulatory approvals.

Completion of the project is anticipated to be in the fourth quarter of 2019.

Northwest Pipeline owns and operates an existing 4,000-mile interstate natural gas pipeline system that runs from San Juan Basin in New Mexico to the Canadian border in Washington at Sumas.

The natural gas pipeline network serves the customers of Puget Sound Energy, Avista Corporation and Cascade Natural Gas among other utilities in the Pacific Northwest and Intermountain region of the country.