GSOE9740 Industrial Ecology and Sustainable Engineering Assignment 3 Brief | UNSW Sydney

GSOE9740 Background:

You are a newly appointed water resources planner for the drought-stricken Murray-Darling Basin in Australia. Growth of demand for agricultural products and climate change are expected to add further stress on future water management in the region. Prolonged droughts in previous years and public concern mean that the authorities must act decisively to plan ahead for the future and secure Water quality threats. 

You have been tasked to assess the sustainability of possible future drinking water supply options for inland South-East Australia. A number of potential water supply augmentation options have been proposed and you are required to provide a quantitative assessment that address a wide range of sustainability concerns.  Water supply decisions must be made on the basis of several criteria, including economic, environmental, political, social, and reliability concerns (Stokes and Horvath, 2006). It is also important to adopt a life-cycle perspective to any water supply option decision, by considering the full supply chain impacts entailed in both the construction and the operation and maintenance phases (Lundin and Morrison, 2002). The triple bottom line (TBL) assessment framework provides an established accounting approach for concurrently quantifying economic, environmental, and social implications for any business decision or project (Foran et al., 2005; Wiedmann et al., 2009; Heihsel et al, 2020

There are two main types of drinking water supply augmentation:

Non-conventional – this refers to non-traditional sources such as treated waste water or desalinated water, increasingly considered as options in more water scarce areas of the world. These water supply options tend to use advanced water treatment technologies. These technologies are nowadays considered highly reliable and can guarantee a given amount of water as they are not subject to climatic influence. The idea of drinking treated seawater or sewage can create a ‘yuck’ factor amongst the public and there are often concerns about the large amounts of energy required for these water sources. Environmental concerns such as brine and sludge disposal also need to be factored in when considering these options.

The three shortlisted drinking water supply options are the following: 

1. Import stream water from further afield. This conventional option has been historically popular in Australia, especially since river originating from pristine mountainous catchments is perceived as being clean and healthy. This option will entail the construction of a new conventional treatment unit. Some possible concerns are the climatic variability and its influence on Alpine flora and fauna.
2. A seawater desalination plant built near the coast. This option uses a membrane-based method know as reverse osmosis (RO) to remove salt from seawater. The de-salted water also goes through disinfection before being supplied to the community. Some possible concerns of this non-conventional option are energy requirements, brine disposal and high operation and maintenance costs.
3. A direct potable reuse treatment train – this entails treating wastewater to drinking level quality and creating a closed water-wastewater cycle. This non-conventional option employs a combination of advanced water treatment processes to produce safe drinking water. Although this kind of option is already successfully employed in arid localities, it tends to be a last resort because of social acceptability concerns.  

Task:

You are tasked with helping the utility board to make the best decision to ensure adequate future supplies for its community. You are expected to adhere to TBL principles and perform a multi-criteria decision analysis (MCDA) using a Weighted Sum Method – Multi Criteria Decision Making.

To successfully complete your assigned task, you must complete the following:

Research the three different water supply options in the literature and summarise your findings in the report. Consider the technologies involved (make sure to employ life cycle thinking!) and list their potential impacts and benefits.