The Australian Gas Light Company (AGL) is putting in place additional Gas-Supply'>gas supply arrangements for New South Wales and the ACT for winter, following notification of reduced gas pressure in the Moomba to Sydney gas pipeline (MSP).
MSP owner, the Australian Pipeline Trust (APT), has notified AGL that it will be implementing a pressure management regime in the MSP due to stress corrosion cracking (minute hairline cracks in the steel pipe - a condition not uncommon in high pressure pipelines) being identified on a section of the pipeline in a remote area of South Australia.
This will result in the pipeline operating at lower pressures than normal over winter.
"As a consequence of these pressure management arrangements, AGL is putting in place additional contingency supply arrangements via the Eastern Gas Pipeline to help meet customer demand during peak times in the winter period. Subject to any unforeseen circumstances, including extended periods of cold weather across South East Australia, AGL believes gas supply to the ACT and New South Wales should be unaffected," AGL group manager external and regulatory affairs Jane McAloon said.
AGL is working closely with APT and the relevant regulatory authorities to ensure the situation continues to be appropriately managed.
"Our portfolio of diversified gas supply arrangements will play an important role in providing us with flexibility to help meet peak demands over the winter period," Ms McAloon said.
A pressure management regime has been established for the 2004 winter months for the Moomba to Sydney Natural Gas Pipeline (MSP).
Stress Corrosion Cracking (SCC) has been identified on the MSP in a remote area of South Australia. Repairs have been effected on the pipeline in five locations by the installation of steel sleeves to restore pipeline integrity.
Further investigative work is planned for next summer. This work may include the insertion of an "intelligent pig" which travels in the gas stream and records irregularities in the steel wall of the pipe.
"Because we are unsure whether further irregularities exist it is prudent for us to limit the pressure in the affected area, and we are altering the configuration of our compressors at Bulla Park to enable us to do so," APT managing director Jim McDonald said.
The work on the compressor station involves re-configuring valving and pipework to permit the compressors to run in series, thereby reducing upstream pressure. APT expects the work will be completed by early July.
"Based upon our previous winter throughput, and provided no extended periods of cold weather affect all of south-east Australia, delivery of gas supply to the ACT and NSW should not be impacted by the pressure management regime," Mr McDonald said.