The Carpentaria Gas Pipeline (CGP) is a transmission pipeline system that extends from Ballera in SW Queensland to Mt Isa.  It transports natural gas from the Ballera gas processing facility to customers in Mt Isa – including the Mica Creek and Diamantina power stations and the surrounding Carpentaria mineral province. It is also an important link between the Northern Territory gas fields and the east coast market via the Northern Gas Pipeline (NGP). The pipeline has a length of 840km, a nominal diameter of 329.3mm and a capacity of 119 TJ/day (Northern Haul) and 65 TJ/day (Southern Haul). 

The lateral pipelines that form part of the CGP are: Cannington Lateral Pipeline (CLP), Mount Isa Mines (MIM) Lateral (DN 150), X41 Lateral (DN 150), Diamantina Power Station Lateral (DPL), Leichardt Power Station Lateral (LPL). The X41 Lateral was commissioned in 2007, the DPL and LPL were comissioned in 2013.

The CGP, which was commissioned in 1998, is owned and operated by APA Group through its wholly owned subsidiaries APT Pipelines (QLD) Pty Limited and Roverton Pty Limited (known as the ‘Carpentaria Gas Pipeline Joint Venture’). When the CGP was first commissioned, South West Queensland Producers (including Santos, Origin and Delhi) had a 30 per cent stake in the pipeline (alongside APA Group’s 70 per cent) but they were bought out by APA Group in 2004, increasing its ownership stake to 100 per cent.

The CGP mainline is subject to light regulation under the NGR. It was originally a full regulation pipeline, but in 2008 the Queensland Government passed a regulation specifying that the CGP mainline would be subject to light regulation and that it cannot be the subject of a full access arrangement until 30 April 2023.