McCourt Street Drainage Basin

To further enhance the amenity of the Public Open Space and the preservation of large existing trees, the Town purchased the property immediately north of the public open space with the view of increasing the playground area but also ensuring the proposed excavations for the drainage works did not compromise the large existing trees.

Michael Cook worked in close liaison with the manufacturer, Graf, to utilise their product ECOBLOC to achieve the required storage volumes. The use of this unique product meant that it was the largest single installation in Australia to date. The site had a number of constraints including tight surrounds limiting the extent of excavations, existing residential homes nearby and surrounding trees requiring protection.

Michael Cook was the lead engineer and he and his co-presenter, Frank Strever, were declared as the winners (as voted by conference delegates) of the Best Conference Presentation for their session about the project at the annual 2019 IPWEA Conference. Several years later, the project is considered a success through greatly improved park amenity and size and most importantly the risk of flooding to neighbouring properties and a nearby electrical transformer is significantly reduced.

Project Requirements

• Infill vacant lot to create a park with playground equipment for improved amenity.
• Address a historical flooding issue in McCourt Street to reduce the risk of flooding to nearby homes and an electrical transformer during major storm events.

Key Sustainability Outcomes

• Reduce peak stormwater flows to already strained downstream stormwater systems.
• Large existing trees were retained.
• Improved amenity and playground for the area.

Key Challenges/Management Strategies

• Ensuring stability during the excavation, the Contractor installed temporary sheet piling to a depth of approximately 4m and used a multi-benched installation approach to achieve the required storage volumes whilst providing adequate working space.
• To minimise maintenance requirements of debris and silt, Gross Pollutant Traps, litter baskets and isolation rows within the ECOBLOC were incorporated into the designs. Isolation rows within the installation were designed to limit the spread of sediment within the ECOBLOC to allow for easier maintenance.