“A community working together, managing water wisely to support a vibrant, sustainable and thriving region."
Canberra has a proud heritage in high-quality water management, refining their development from highly engineered urban waterways to appreciating and implementing natural processes for water quality management.
Since 2005, Water Sensitive Urban Design (WSUD) has been trialled and adopted in the ACT to better protect their urban waterways, lakes and ponds, and ultimately contribute to a more sustainable urban community. The strategy also sought to rectify inconsistencies in ‘best practice’ across the region caused by an absence of specifications available for WSUD infrastructure in the ACT.
To mitigate the urban impacts on their waterways, implementing quality WSUD infrastructure specifications is intrinsic for the Canberra region as it encourages reduced mains water use, improved stormwater quality and managed stormwater flows and promotes greywater reuse.
The project involved the development of the Municipal Infrastructure Standard (MIS) and Technical Specifications (MITS) for WSUD Infrastructure, and incorporate new technologies and align with Australian best practice standards. They reflect current knowledge and best practice, and are underpinned by local ACT experience derived from constructing, operating and maintaining stormwater and WSUD systems since the 1980s in order to meet the ACT Government’s objectives. The documents facilitate the actualisation of the ACT Water Strategy, enabling a sustainable future for their community through a strategically naturalised and improved environment.
The project intrinsically considered environmental outcomes by creating documents that:
- Govern the safe conveyance of runoff to a receiving water body without causing flooding, loss of lives, or compromising the safety of people and damage to property.
- Minimise the impact of urbanisation on the environment through stormwater quality and quantity targets.
- Consider and minimise the potential impacts of climate change on the environment by making an allowance on rainfall intensity, and by undertaking a sensitivity analysis.
- Better accommodate the stochastic nature of rainfall by adopting the latest approaches promulgated in the Australian Rainfall and Runoff guidelines.
- Improve outcomes from implementing better design standards.
- Reduce the risk of flooding and pollution.
- Advance the quality of life for the people and the community.
- Supports better landscape outcomes with enhanced aesthetics.
- Provides opportunities for passive recreation and relaxation for the public, resulting in social benefits.
It was recognised in the ACT (by consultants and ACT Government authorities) that clear guidance on planning, design and documentation of WSUD devices was lacking. While documents are available from interstate agencies and organisations these are not directly applicable in Canberra. Additionally, ARR2019 was released with improved methods for runoff estimation.
Design and documentation was being undertaken based on what consultants perceived to be best practice. Whilst consultants made every effort to bring the best practice to their projects, there was limited consistency between projects and a lack of benchmarks against which approving authority could assess submitted designs and documentation.
The development of the standard and specifications for WSUD infrastructure was based on:
- A review of available design standards and guidelines for the WSUD device across Australia;
- Formulation of guidance on the modelling of the performance of the device, as appropriate;
- Development of a standard suitable for the design and documentation of the device in the ACT; and
- Formulation of a Technical Specification for construction of the device.
A recent review indicated that the 2019 stormwater standards and specifications have seen a rapid uptake for WSUD design and result in consistent, well developed, value-for-money engineering outcomes through easily constructible design and documentation, and tangible and intangible benefits. Incorporating the maintenance considerations is beneficial to the environment and the community, as it ensures the measurement effectiveness is maintained into the future and leads to the sustainable use and management of stormwater.
Proactive and consistent collaboration between Cardno, ACT Government – Transport Canberra and City Services (TCCS) and stakeholders significantly contributed to the success of the project. Continuous communication throughout the project ensured a completely integrated approach during all phases. for statutory planning, technical design, infrastructure construction, and infrastructure operation and management.
Cardno provides innovative solutions to complex project challenges:
For more information contact:
Business Leader – ACT
Principal / Senior Civil Engineer