TC Energy’s Gas Transmission Northwest (GTN) has secured approval from the US Federal Energy Regulatory Commission (FERC) for the planned Gas Transmission Northwest XPress Project (GTNXP).

The GTNXP involves upgrading three existing compressor stations on the GTN system, which was commissioned in 1962 to transport natural gas for the Pacific Northwest region of the US.

These compressor stations are located in Idaho, Washington and Oregon.

With the approval, the company is allowed to install, construct, modify and operate certain natural gas compression facilities at the existing No. 5 Athol, No. 7 Starbuck, and No. 10 Kent Compressor Stations, located in Kootenai County, Idaho, Walla Walla County, Washington, and Sherman County, Oregon, respectively.

The project is 100% subscribed under precedent agreements with shippers including Cascade Natural Gas, Intermountain Gas Company and Tourmaline Oil Marketing.

The project is expected to increase GTN’s existing transmission system capacity by around 150 million standard cubic feet per day between Idaho and Oregon.

However, the FERC’s approval is being opposed by environmentalists..

Commenting on the approval, Washington Governor Jay Inslee said: “The federal government has finally begun making tremendous climate investments under the Inflation Reduction Act, but this decision essentially digs the hole deeper and locks in long-term capital investments that prevent us from reaching our national and state goals.

“This decision also runs contrary to Washington state laws that require our utilities to transition to 100% clean energy by 2045 and will leave consumers on the hook for a costly stranded asset. Our new building codes focus on increasing clean energy for homes and offices.

“Expanding this fossil fuel pipeline for 50 years – until 2073 – saddles our children and their children with climate harm and fossil fuel costs.”

Nonprofit environmental group Columbia Riverkeeper said it would appeal the FERC’s decision on the pipeline expansion project.