Located in Logan, one of Queensland’s fastest growing areas, the Cedar Grove Environmental Centre (CGEC) is catering for a rapidly expanding population as well as the environment.
Funded by Economic Development Queensland and delivered by a public and private sector partnership involving Logan Water, Downer, Cardno and WSP, the project is set on a 204-ha site located on the Logan River at Cedar Grove. It comprises a state-of-the-art wastewater treatment plant (WWTP), 7 ha of constructed wetlands, vegetation corridors, community facilities including 2.5 km walking track along the Logan River, picnic tables and amenities, as well as a Landcare nursery, a solar farm and 37 hectares of biodiversity offset planting.
To meet strict environmental requirements, the site features the state’s first WWTP to benefit the environment through membrane bioreactor technology with constructed wetlands to achieve record low nutrient levels and offset remaining nutrients through catchment restoration.
To deliver the project, WSP provided services involving design visualisation tools (utilised for design and operability reviews); structural design; electrical design, pre-commissioning and commissioning; instrumentation and controls design; development of 3D interactive operation and maintenance system; odour and noise assessments; cultural heritage assessment; environmental assessment and management; ecological assessment and management; compliance management; rehabilitation works; and operational management plan for the wider site.
Delivering a sustainable water future
WSP has proudly been part of the Logan Water Partnership delivering value to the Council’s customers and communities since 2009.
Community and environmental uses occupy 95 per cent of the 204-hectare site. The area is home to 120,000 native trees and shrubs, some of Logan’s oldest recorded Queensland Blue Gum trees and more than 20 bird species.
The site’s sustainability credentials include:
- The production of very low nutrient effluent through the use of membrane bioreactor technology and the construction of wetlands that further filter the effluent with the aim of a total nitrogen release of 1mg/litre and total phosphorous release of 0.5mg/litre.
- Integration of the WWTP’s reclaimed water outfall pipeline in a fish ladder on Seqwater’s weir on the Logan River to replace water released and maintain environmental flows. This preserves 3.3ML of water per day in the weir pool as a future drinking water resource.
- Future reuse of reclaimed water from WWTP for recycling to agricultural irrigation.
- Rehabilitation and replanting the upstream banks of the Logan River to reduce nutrient-rich sediment from entering the waterway.
- Planting native trees on 37ha of the site to offset approved vegetation removal by developers across Logan.
- An on-site 150 kW solar farm to contribute energy for the facility’s operations.
- Longest ever Horizontal Directional Drill (HDD) of 1.3 km used to reduce vegetation clearing around waterways and protect koala habitat.
Awarding excellence
The project combined cutting edge wastewater treatment technologies with environmental enhancement, community-led site master planning and innovative project delivery methods. What began as a WWTP project has been reimagined as a sustainable community and environmental asset to benefit today’s residents and future generations.
Alongside its delivery of social, environmental and economic benefits, the project has won numerous industry awards for innovation including Engineers Australia 2020 Australian Engineering Excellence Award for Queensland.
