Overview

In September 2013, AGIG partnered with Chevron to develop, build and operate the Wheatstone Ashburton West Pipeline (WAWP), a 109km, 16-inch pipeline consisting of the Wheatstone Lateral and Ashburton West Loop, alongside the refurbished 87km, 10-inch Ashburton West Lateral.

Key works included:

  • Upgrading the existing 10-inch pipeline from Ashburton West to DBNGP Compressor Station 2
  • Building an adjacent 87km, 16-inch loop pipeline
  • Constructing a 22km, 16-inch connection to Wheatstone

Backed by a 30-year take-or-pay contract, the project offers 337 TJ/day capacity with future expansion to 600 TJ/day.

Project Overview

In September 2017, we began commercial operations of Tubridgi for Citic. This is located 25km west of Onslow in very close proximity to the Chevron operated Wheatstone gas plant and BHP operated Macedon gas plant, and adjacent to the Ashburton West facilities. Tubridgi is 100% owned and operated by AGIG, and serves all the state’s major gas consumers and producers via a pipeline network that connects Tubridgi to the Dampier Bunbury Natural Gas Pipeline (DBNGP). 

Operation

Post construction, the commissioning team mobilised. The same process was followed as the Fortescue River Gas Pipeline, including all mechanical and electrical checks of safety valves, metering systems and the Supervisory Control And Data Acquisition (SCADA) remote communications. Once signed off and regulatory approval granted, the pipeline was purged with nitrogen to remove the air in the line before introducing natural gas. The system pressure was incrementally increased with system checks at each megapascal (MPa) of pressure. 

Once the pipeline passed all commissioning checks, the system was handed over to operations in the electronic asset management system. This ensured the Asset Management Plan and associated processes developed by the in-house technical and operations teams were functional for operations. Based on these processes, the operations team will undertake preventative and corrective maintenance for the entire life of the pipeline.

 

Practical completion

AGIG achieved practical completion of the Wheatstone Ashburton West Pipeline in December 2014, with domestic gas deliveries from the Wheatstone plant commencing in 2019.