Yarra Valley Water

Donnybrook Link Branch Sewer Stage 2


Sewer main

Contract Type


Year of Completion




Sustainable Wastewater Upgrade

Catering to the needs of Melbourne’s expanding northern corridor, this project aids in developing sustainable urban communities by improving wastewater management and sanitation infrastructure.

Project Overview

Yarra Valley Water engaged Diona to upgrade Melbourne’s northern sewer network, installing a 3.8 km GRP branch sewer. Despite encountering challenges such as navigating sensitive habitats and demanding ground conditions, Diona’s team delivered the project successfully.

Project Need

To accommodate future development in Melbourne’s northern growth corridor, Yarra Valley Water identified the imperative need to upgrade the sewer network. This new pipeline will ultimately provide sewerage services to over 16,000 properties.

Project Solution

Diona undertook the Donnybrook Link Sewer Stage 2 project which involved installing a 3.8 km GRP branch sewer, ranging from 650 to 860mm in diameter, inclusive of 13 GRP maintenance holes, and decommissioning the existing pump station. The installation involved 1.2 km of open-cut trenching, varying from 4m to 8m, and 1.2 km of micro-tunnelling at depths of 8m to 16m, amidst varying hard rock and ground conditions.

Diona overcame numerous challenges, such as working within sensitive flora and fauna habitats and navigating multiple micro tunnels, including successfully tunneling under the Hume Highway.

Value Add | Benefit
Environmental Sensitivity

Diona’s successful navigation of sensitive flora and fauna habitats highlights our commitment to environmental stewardship, ensuring minimal impact on the surrounding ecosystem during project execution.

Efficient Construction Techniques

The utilisation of open-cut trenching and micro-tunnelling demonstrates innovative and efficient construction methods, allowing for the completion of the project in varying ground conditions while minimising disruption to the surrounding environment.

ESG Alignment

By upgrading the sewer network with modern infrastructure and employing innovative construction techniques like micro-tunnelling, the project reduces environmental impact compared to traditional methods. This includes minimising disruption to sensitive habitats and ecosystems.

The project improves sanitation infrastructure for the community, ensuring better health and hygiene outcomes for residents. Additionally, by providing sewerage services to over 16,000 properties, it supports public health and quality of life in the region.

The project’s enhancement of the sewer network, which will service over 16,000 properties, supports the goal of ensuring availability and sustainable management of water and sanitation. It contributes to improving wastewater management and sanitation infrastructure in the growing region.

The installation of GRP branch sewer, including deep microtunnelling and open cut trenching in varied ground conditions, showcases innovation in infrastructure development. This technical complexity underlines Diona’s commitment to resilient infrastructure and innovative construction methods.

By catering to the needs of Melbourne’s expanding northern corridor, the project contributes to the development of sustainable urban communities. Adequate sewage handling is essential for urban sustainability, affecting the overall health, hygiene, and quality of life in these communities.

The collaboration between Yarra Valley Water and Diona represents a partnership aimed at achieving sustainable development goals, highlighting the collaborative efforts needed for complex infrastructure projects.