Domestic Water End Use Study: An Investigation of the Water Savings Attributed to Demand Management Strategies and Dual Reticulated Recycled Water Systems

Abstract

Rainfall patterns in Australia have altered in recent decades, with trends of lower rainfall across densely populated southern areas recorded. Such drastic changes in climatic conditions have triggered a re-evaluation of traditional techniques and methods to manage urban water demand and supply. Throughout the nation, movement towards sustainable urban water resource management is becoming the norm. This water security method involves the planning and implementation of a range of water supply, demand management and source substitution initiatives to meet short term demand and provide long term supply security to urban populations. Examples of these initiatives include: desalinated potable water, water restrictions, water efficient fixtures, awareness campaigns, dual reticulated recycled water supply and on-lot rainwater tanks. In the urban water planning and management industry, these initiatives are relied upon to provide alternative potable supply types and reduce average daily water demand. Predictions and estimations of the potable water savings attributed to water demand management and source substitution measures are often assumed and included in city-wide planning and forecasting documentation. These water demand management and source substitution measures play a significant part in meeting projected city future demand however, these initiatives are all too often planned and implemented without validation of actual potable water savings. Some examples of measuring potential savings through bulk demand reductions are documented although this often involves further application of estimations for other influencing factors such as climate, household makeup and leakage. Understanding the actual potable water savings attributed to water demand management and source substitution initiatives requires the application of end use water consumption monitoring due to the need to establish the point of source savings related to these measures. Significant residential end use water consumption studies have been carried out in Perth and Melbourne in Australia and, in the United States of America. These investigations have ascertained the unique consumption behaviours of residents in the monitored location and presented some examples of measuring water savings attributed to water efficient devices. The variation in end use consumption between the studies and the useful application of results from these investigations has prompted the encouragement of further research in this field. To date, no statistically significant end use water consumption study has occurred in the state of Queensland, Australia. In response to the current gaps in the body of knowledge, this research focused on determining end use water consumption and investigating the end use savings attributed to water efficient fixtures, resource consumption awareness devices, and dual reticulated recycled water supply regions in the Gold Coast, Australia. This study also investigated the relationship between attitudes towards the environment and water conservation and the impact that this had on end use water consumption. The research also developed end use diurnal patterns of consumption for both single and dual reticulated regions on the Gold Coast.