Sustainability Index
Sherri Cook, CU

Research Approach

This activity will develop and implement a sustainability index in order to comprehensively evaluate which treatment technologies are most appropriate and sustainable for small drinking water systems. This index will use sustainability assessments to systematically evaluate the environmental, social, and economic impacts of traditional and innovative drinking water treatment technologies. This sustainability tool will combine the frameworks of sustainability assessment methods (e.g., life cycle assessment and costing) with more specific drinking water treatment capacity (EPA, 2012; RCAP, 2010) and effective utility management (EPA et al., 2008) assessments. Overall, this information will be combined with data from Activity #1’s Risk Index to determine a recommendation of treatment options (in Activity #4).

A sustainability assessment and index will be developed for application to small drinking water treatment systems by evaluating and quantifying the three pillars of sustainability—environment, society, and economy. Figure 1 shows the overall approach that will be used to assess and improve the comparative sustainability of traditional and innovative drinking water treatment technologies. This sustainability index relies upon data collection from the literature as well as from Activities 3 and 4, which will focus on a community technical, managerial, and financial capacity and the training needs and demands of a small system. Activity 6 will provide site- and technology- specific data along with stakeholder feedback about the technology and the sustainability assessment. Finally, the sustainability assessment will determine sustainability ratings of different technologies and this information will be combined with Activity 1’s risk index in order to provide a comprehensive analysis of alternatives in Activity 4’s leg 3.

For the sustainability index, site-specific data (i.e., source water quality, energy costs, etc.) is needed to evaluate technology options, which will consist of various combinations of technologies for drinking water treatment. Each technology option’s performance (i.e., water quality) and treatment requirements (i.e., energy demand, chemical usage, etc.) will be assessed with treatment performance sub-models. These performance sub-models will use currently known information from the literature as well as data generated from this Center’s innovative technology research, specifically data collected during Activities 4 and 6. Collected data and data generated from these technology option sub-models will then be used to evaluate the comparative sustainability of each technology option.

A variety of methods and metrics (IOS, 1997; EPA. 2010; Goedkoop & Spriensma, 2000) are employed in order to quantitatively assess the environmental, economic, and social impact of each treatment option. The economic impact will be quantified using life cycle costing methodology and costing databases. To elucidate the social impact of different technology options, a compilation of assessment techniques, which include social life cycle assessment methodology (Jørgensen, Bocq, Nazarkina, & Hauschild, 2008), Activity 4’s managerial and financial capacity analysis, and Activity 3’s training assessments. Data will be categorized by type of social impact; example categories are: job creation (number of jobs created or eliminated); training requirement (time for training, such as employee hours); and community acceptance (dollar amount willing to pay for service). The social impact of a technology option will be calculated as a weighted sum across the social impact categories. For each sub-model and assessment, a Monte Carlo analysis will be used to estimate the aggregate impact of assumption and parameter uncertainty. Finally, the overall sustainability rating will be calculated as the weighted sum of the output from each the environmental, economic, and social impact assessments. Stakeholder engagement and input will be central to this weighting scheme.