Dohertys Drain

Aerial view of housing estate to see drainage situation

A large residential development in Melbourne’s growing west was the site for an expansive nature conservation area with an active creek supporting native flora and fauna. The Cardno multi-disciplinary team provided services for the design and construction of complex drainage works through the site, to manage the interface with the Federation Trail and preserve sensitive waterway ecologies.

The development, comprising 900 residential lots, is positioned in nearby grassland reserves that play a vital role in the local ecosystem, providing protection for endangered golden sun moths and native plants. Dohertys Drain is a Melbourne Water constructed waterway draining a large upstream developed catchment, conveying 42cumecs at peak flood events. Drainage works were required downstream of the site under Palmers Road and through the neighbouring property for this stage to be developed.

Since the downstream landowner would not allow temporary works on his site, the Central Equity Limited and Cardno teams were required to design and deliver 650 m of constructed waterway downstream, costing $4 million.

Taking five years to complete the planning and approval process, the drainage works project team were faced with many obstacles. These included coordinating multiple design disciplines, defining goals and developing realistic deadlines for the many stakeholders, from local and state government offices, authorities to utility companies.

The project required the design, documentation, tender and construction for Dohertys Drain, Drainage Scheme Works:

  • 650m length of open earth drainage channel
  • 40m length of 20m wide multiple box culvert cells under an existing gas transmission pipeline

Multiple disciplines within Cardno provided significant contributions to the project:

  • Urban Infrastructure – Land Development and Construction Teams
  • Water & Environment
  • Geotechnical
  • Building – Structures

We celebrate Stephen Warner and the project team for their effective collaboration amongst the internal and external teams, and for setting stakeholder engagement expectations, which was the foundation of this project delivery.

Project Accomplishments

Aerial view of drainage situation
  • Managing the interface with the Federation Trail and preserve sensitive waterway ecologies
  • The interface with the upgrade of Palmers Road as part of the Suburban Roads Upgrade, which delivered the new culverts required under Palmers Road
  • Crossing of an existing gas transmission pipeline required a 40 m length of 20 m wide multi box culvert cells to be constructed under the pipeline.
  • Recoating the gas pipeline prior to the culvert works, requiring the coordination of the authorities contractor and the construction of a separate access track through an ephemeral watercourse.
  • Flood management during construction. Runoff from the large developed upstream drainage catchment has flooded the construction site in several rain events.

The strong collaborative stakeholder relationship formed over the years has resulted in ensuring timely deliverables and collective decision-making on issues faced every day, to achieve the best project outcome. This was particularly pertinent when the works site in an active creek received over 40 mm of rain causing a disruption in the work progress.