CASE STUDY Toowoomba Regional Council Tackles the Challenges of a Failing Common Effluent System Using SewerGEMS Bentley Software Helps Council Compare Conventional Gravity and Pressure Sewer Systems to Recommend Optimal System

TRC undertook a study in 2011 focusing on the township of Crows Nest as its flagship for assessing the existing infrastructure and the development of a future sewer system. The study was designed to identify whether a conventional gravity system would be a more cost-effective option than a pressure sewer system. Consideration of various conditions such as population densities, topographic constraints and the presence of the existing infrastructure were all major factors important to TRC. The need for improved water quality, better-performing sewer systems, and reduced capital costs were the primary objectives, but TRC also had to ensure regulatory requirements were met when choosing the most effective system. Using Bentley’s SewerGEMS for sanitary and combined sewer modeling and analysis, TRC engineers assessed that AUD 2 million could be saved building a conventional gravity system instead of a pressure sewer system. In a region that is facing catch-up challenges from recent significant flooding and other issues, if correct planning can be implemented via the use of software and some out-ofthe-box thinking, significant cost savings can be realized for the community.