Zinfra’s solution was a temporary by-pass pipe on the bridge walkway, enabling a new plastic main to be inserted into the existing old main under the concrete. This helps maintain supply to the customers downstream and resolves integrity issues along Toukley Bridge which is a section of State Road B70.
Working in partnership to deliver the right outcomes
Zinfra works in collaboration with asset owner Jemena to service and maintain its gas distribution network. An over 200-strong team is stationed in NSW, providing gas services, repairs and maintenance from strategically located depots in Sydney, Central Coast, Wollongong, Newcastle and country NSW. Over 900 calls per month are received by Zinfra for our 24/7 emergency response and maintenance service to ensure gas supply to Jemena customers is maintained. Toukley Bridge’s leak was one such call, requiring an immediate response by Zinfra’s team, given the potential community impact.
Toukley Bridge connects the Budgewoi peninsula and townships of Toukley, Noraville and Norah Head and Gorokan at the midpoint between the Budgewoi and Tuggerah lakes, Central Coast region of NSW, approximately 100km from Sydney towards Newcastle. The section of pipe that was leaking was installed in 1990 and is a 100mm steel one-way feed laid in the bridge duct running for approximately 210 metres, and the only gas supply into the area. Two(2) shopping centres, multiple aged care homes and many resorts are situated on this peninsula given its proximity to both the lake and beach; and it is also a popular retirement area. Considering the number of commercial customers, maintaining a consistent gas supply is paramount.
The partnership between Jemena and Zinfra Gas Services personnel saw numerous meetings held, drawing from the extensive field knowledge of our Repairs and Maintenance supervisors/Team Leaders, Asset Management, Steel Mains Inspection officer, and Zinfra’s Central Coast / Hunter Region contractor, M&E Pratt, to brainstorm a solution. A plan was formulated and preparations commenced.
Planning for the works involved; applying for walkway/road closures, Transport for NSW (TfNSW) and local council (Central Coast Council) approvals, Acid Sulphate Soil/ environmental risk assessments, delivery and stockpiling of materials and storing equipment on site. Discussion took place with all key stakeholders to gain verbal agreement and formal approvals.
These approvals can take up to three months to obtain however Zinfra, over many years, has built a comprehensive, trusted working relationships with local emergency management committees, local councils and TfNSW so was able to secure the necessary safety and authority approvals for the project within one month, delivering a fast, reliable service on this leak to Jemena.
Tuesday 7th April saw a by-pass being commissioned and the section of main being isolated. Gas pressures were monitored in the afternoon and throughout the night to ensure the ByPass could keep supply to the downstream customers. On Wednesday 8th April, the gas main was depressurised by burning off the remnant gas using a purge trailer and the steel was inserted with a new PE gas main. After testing the new installation, the new gas main was purged and put into service. The purge trailer is specialist equipment which enables gas to be safely burnt off.
Ensuring safe, efficient gas supply to the community affected, Zinfra drew on long-standing relationships and leveraged the industry expertise in both Zinfra and Jemena to effectively repair this section of gas main.