Managing interactions between decentralised and centralised water systems (Project C3.1)

Overview

Water management strategies in all Australian cities include initiatives to reduce water consumption and supplement water supplies with alternative or decentralised systems that produce water with fit-for- purpose quality from locally available sources such as stormwater and greywater.

The use of decentralised systems will not only reduce the demand for centrally supplied water, but also change both the flow and composition of wastewater discharged to sewer networks that collect and transport wastewater to centralised wastewater treatment facilities. The latter will potentially have very significant implications on the management of corrosion, odour and greenhouse gas emissions in sewer networks.

This project aims to assess the interactions between decentralised water treatment and reuse systems and central infrastructure to support and optimise the integration of decentralised and centralised systems.

Key outcomes

The project will deliver decision-support tools and guidelines to support state and local governments and water utilities in managing water demand and the interactions between centralised and decentralised systems.

One important project outcome is the enhanced SeweX model. The current model, developed by the University of Queensland, describes in-sewer physical, chemical and biological processes. The enhanced SeweX model will be able to predict the effect of reduced sewer flow and changed wastewater characteristics on sewer management. A platform for integrating three models (SeweX, water distribution network model EPANET and International Water Association’s ASM, ADM) is being developed to aid decision making on the most appropriate model.

In addition, a methodology for improving financial and environmental performance forecasting (including water balance) of decentralised systems is being developed which addresses uncertainty in climatic conditions, urban growth and end use demand. This will aid in improving the integrated design and operation of multiple-source water supply systems applicable to greenfield developments and city infill rehabilitation.