The Gas Supply (Gas Quality Specifications) Act 2009 (the Act) recognises that some gas transmission pipelines in Western Australia may be particularly sensitive to changes in gas quality because they are fully utilised or operating close to capacity.
The Minister for Energy may declare these pipelines to be a Pipeline Impact Agreement (PIA) pipeline. WA currently has two PIA pipelines:
- Dampier to Bunbury Natural Gas Pipeline – Dampier to Bunbury Natural Gas Pipeline declaration (PDF) (26 June 2010)
- Goldfields Gas Pipeline – Goldfields Gas Pipeline declaration (PDF) (2 December 2015)
Pipeline Impact Agreements
Gas producers that want to deliver gas into the Dampier to Bunbury Natural Gas Pipeline or the Goldfields Gas Pipeline that is outside their reference specifications will need to enter into a Pipeline Impact Agreement with the pipeline operator.
The purpose of a PIA is to ensure the pipeline operator is not disadvantaged by the introduction of broader specification gas. The agreement identifies the impacts of the proposed gas supply and sets out how those impacts will be addressed.
A PIA does not take effect until 18 months after agreement is entered into, giving pipeline users time to prepare for any change in gas specification and protecting the pipeline operator from adverse consequences.
Standard Form Pipeline Impact Agreements
The gas quality framework provides for default or “fall back” PIAs which a gas producer may elect to use if it cannot agree with a pipeline operator on the terms of a PIA.
The standard form warehousing method PIA for the Dampier to Bunbury Natural Gas Pipeline is available here: Pipeline Impact Agreement (standard form).
Existing Pipeline Impact Agreements
| Pipeline | Gas producer | Gas field(s) or production facility | Date PIA entered into |
|---|---|---|---|
| Dampier to Bunbury Natural Gas Pipeline | Woodside Burrup Pty Ltd (Pluto) and Woodside Energy Ltd (Scarborough) | Pluto and Scarborough | 2 July 2025 |
| Dampier to Bunbury Natural Gas Pipeline | Woodside Energy (Australia) Pty Ltd and Santos WA PVG Pty Ltd | Macedon | 25 June 2021 |
| Dampier to Bunbury Natural Gas Pipeline | MEPAU Perth Basin Pty Ltd | Xyris Production Facility | 1 July 2020 |
| Dampier to Bunbury Natural Gas Pipeline | Woodside Burrup Pty Ltd | Pluto | 12 June 2020 |
| Dampier to Bunbury Natural Gas Pipeline | BHP Billiton Petroleum (Australia) Pty Ltd and Apache PVG Pty Ltd | Macedon | 1 September 2011 |
When gas producers enter a PIA, they must provide summary information about the PIA to the Australian Energy Market Operator (AEMO) within 20 business days. The information to be included in the summary (known as PIA Summary Information) is set out in section (7)(1)(a),(b),(c) and (d) of the Act.
PIA Summary Information for existing Pipeline Impact Agreements are available on the WA Gas Bulletin Board, here: Gas Bulletin Board (WA)
Exemptions
The Minister for Energy may shorten the 18-month period before a PIA takes effect if they are satisfied that it will not materially affect operators of PIA pipelines, operators of other transmission and distribution pipelines, gas storage facilities, or gas consumers.
To date, the Minister has approved shortening the 18-month period for two PIA:
| Pipeline | Gas producer | Gas field(s) | Date exemption granted |
|---|---|---|---|
| Dampier to Bunbury Natural Gas Pipeline | Woodside Burrup Pty Ltd (Pluto) and Woodside Energy Ltd (Scarborough) | Pluto and Scarborough | 10 September 2026 |
| Dampier to Bunbury Natural Gas Pipeline | Woodside Burrup Pty Ltd | Pluto | 30 April 2020 |
PIA pipeline higher heating values
PIA pipeline operators have been required to provide the daily average higher heating value (HHV) of the gas stream for publication on the WA Gas Bulletin Board since its commencement in August 2013.
Prior to that time, the information was published separately by the Public Utilities Office.
For the average HVVs of PIA pipelines from 1 August 2013 to today, see: Gas Bulletin Board (WA)
The average HHVs from 1 January 2013 to 31 July 2013 are available here:
- Goldfields Gas Pipeline (PDF).
