[3] The pipeline runs within Western Australia from a point near Withnell Bay, on the Burrup Peninsula near Dampier, to Bunbury in the south-west of the state.

The other main inlet point is approximately 135 kilometres (84 mi) south of Dampier, where one of the sales gas pipelines from Varanus Island Processing Hub connects with the DBNGP.

In June 2008, following a pipeline rupture and explosion at the Varanus Island facility, the DBNGP carried additional volumes of gas from the North West Shelf plant to the south-west of the state, for a period of several months.

As a single trunkline it is 1,530 kilometres (950 mi) long,[4] extending from the Burrup Peninsula in the Pilbara region, to Bunbury in the south west of Western Australia.

It supplies gas to industrial, commercial and residential customers in Perth and major regional centres along the pipeline route.

[2] The idea of a pipeline to transport gas from the North West Shelf to the south-west of Western Australia had its origins in 1975, following the discovery of large offshore reserves by WAPET and Woodside Petroleum.

The developers of the North West Shelf were in the preliminary stages of planning a system of production facilities based on the Rankin and Goodwyn fields (located about 130 kilometres (81 mi) off the coast of Dampier), linked to a liquefied natural gas processing plant and a domestic gas plant situated at Withnell Bay.

The DBNGP is currently owned and operated by Dampier Bunbury Pipeline (DBP), part of the Australian Gas Infrastructure Group (AGIG), Australian Gas Infrastructure Group is owned by various consortia of Hong Kong-based entities listed on the Hong Kong Stock Exchange.

The effect of looping is to provide additional capacity at critical sections of the main trunkline, thus increasing the total possible throughput.

The expansion projects also required upgrade works on the pipeline's compressor stations, control and communications systems and metering equipment.