Mulgra Street, Frankston South – Emergency Works
Abergeldie, in joint venture with BMD and KBR (ABKJV), successfully delivered the Mulgra Street Emergency Works project in Frankston South for South East Water under a Design and Construct (D&C) contract. Triggered by rapid creek erosion exposing a live sewer asset, the project required rapid mobilisation, disciplined planning and close collaboration to progress design, approvals and construction activities while managing a complex delivery environment.
The completed works have extended the operational life of a critical sewer asset by more than 50 years, improving the long-term resilience and reliability of critical sewer infrastructure while transforming a degraded section of creek into a stable, rehabilitated and visually enhanced waterway.
The project was recognised with a CCF VIC Earth Award in Category 1 for projects valued at up to $2 million, highlighting the team's successful delivery of the works.
Scope of works
The D&C scope of works included:
- Stabilisation of the creek bed and surrounding embankment.
- Protection and encasement of the live sewer asset.
- Deep excavation and subgrade improvement beneath the sewer.
- Construction of erosion protection measures, including rock beaching and a concrete nib wall.
- Environmental rehabilitation, including removal of contaminated material and revegetation with native species.
Adaptive delivery in a constrained environment
Working within a live creek environment and a restricted summer construction window, the project required careful planning and close collaboration from the outset. Early engagement with stakeholders and regulators helped secure the approvals pathway needed to progress works within the available seasonal timeframe, ensuring construction activities could be completed during the available season and avoiding delays that would have deferred works until the following year.
When unstable ground conditions were encountered beneath the sewer asset, the team adapted the construction methodology and worked closely with geotechnical specialists to safely stabilise the subgrade and protect the live sewer. This flexible approach enabled the project to maintain momentum while responding to changing site conditions.
Innovative infrastructure protection
Faced with a live sewer asset, constrained access, and a sensitive creek corridor, the team developed an alternative methodology to avoid full sewer replacement. By temporarily supporting the asset and undertaking staged excavation and stabilisation works beneath it, the team maintained sewer services, reduced environmental impacts and minimised disruption to the surrounding community, while delivering a more efficient construction outcome.
Delivering a legacy
The project delivered lasting benefits for South East Water, the local environment and the surrounding community. Beyond protecting critical infrastructure, the works transformed a heavily degraded creek corridor through erosion control measures, removal of contaminated material and revegetation with native species. The result is a stable, resilient and visually enhanced waterway that will continue to support environmental health while improving the long-term performance of the surrounding infrastructure network.