CIB W116—Smart and Sustainable Built Environments - Test Input

prolong asset life cycle and identify optimum interventions. The proposed methodology involves a
hierarchy of indicators mimicking the organizational structure of municipalities, using aggregation to
form higher levels of indicators. The guide provides a set of examples of the relationship between the
different levels of indicators, and presents a list of qualities that chosen indicators should have:
manageable, relevant, meaningful, measurable, well-defined, and aligned with objectives.
Wright (2007) describes the sustainability of infrastructure as “essential to a sustainable society”
(2007, p.1) and presents an assessment methodology based on performance indicators. The author
describes the characteristics that these indicators should have, but does not attempt to develop the
indicators, or describe how, or at what level they should be implemented (macro/micro/project).
3.3.1 Project level
Dasgupta and Tam (2005) approach the consideration of sustainable infrastructure from a project
perspective. Indicators are developed and presented to assess project sustainability of Civil
Infrastructure Systems (CIS) in all life stages, including preproject planning, project implementation
& ongoing operations. Noticeably absent from “all life stages” is the consideration of end-of life. The
authors concede that there are “many cases where the post-use stage also becomes significant” (2005,
p.31) but have chosen to put end-of-life outside of the system boundaries for sake of simplicity. The
indicator system does not attempt to actually address the sustainability of the system, but only
compare given alternatives and makes a determination of which is less bad. “…the discussion is
limited to comparing modification options with similar sets of project specific issues of concern”
(2005, p.34). No attempt is made to reconcile the trade-offs between the negative environmental and
potential positive societal goals of the project schemes.
Ding (2005) presents the methodological basis for the development of a sustainability index
incorporating economic, social, and environmental criteria with both monetary and non-monetary
approaches. The system allows trade-offs with a multicriteria algorithm, ranking projects and facilities
based on their “contribution to sustainability,” and choosing the most efficient option among
competing alternatives. The author uses an “industry survey of professionals in the construction
industry” (2005, p.6) presented in a prior paper to identify important criteria that are then ranked and
aggregated, resulting in a sustainability index consisting of four criteria. The author accepts that
changing the weighting would change the results, but does not explain the rationale behind the
choices made in the case study, nor conduct a sensitivity analysis to explore the impact.
Ugwu and Haupt (2007) use a survey to develop a set of indicators for project-level sustainability
appraisal, based on an interpretation of goals related to the sustainability of infrastructure. The survey
is a convenience sample of 49 “industry stakeholders attending a series of national health and safety
workshops and seminars” (p. 668) with a 100% response rate. The study does not attempt to define or
clarify the actual meaning of sustainability at the macro or project level, though it discusses both in
detail. The paper does not attempt to discern whether any of the options present a truly sustainable
option, only which of the project alternatives is the better option, using a sustainability index derived
from the indicators as criteria. The sustainability index itself is subjective in its weighting and
methodology, and depends entirely on a subjective choice of indicators.
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