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MPhil in Engineering for Sustainable Development

global challenges, engineering solutions

Assessment of Key Factors in the CAWST Theory of Change

Safe and reliable access to water, sanitation, and hygiene (WASH) is one of the most pressing problems to solve in developing countries. However, it has been consistently reported that water and sanitation projects have staggering failure rates. More than often the same projects that were designed to improve the quality of life of people have negative consequences on the health of living beings and society. The failure of these initiatives is not only just attributed to technical quality anymore, but rather to a web of interlinked aspects which include societal, environmental, financial, and institutional factors. This dissertation aimed to critically assess these factors which have a direct impact on the effectiveness of non-piped WASH projects. This study was guided by a theory of change developed by the Centre for Affordable Water and Sanitation Technology (CAWST). A theory of change is a useful approach to evaluate and guide development programs, in which a set of necessary factors to achieve a specific outcome are interlinked and shown in complex diagrams. The research methodology involved three stages: a structured literature review, a quantitative analysis of surveys, and a qualitative analysis of interviews.

The results of this study demonstrate that institutional, technical, financial, as well as social factors are all necessary to implement an effective WASH project, but neither is sufficient. Moreover, community participation, the sustainability of a project, and environmental aspects must be considered, and they constitute requirements to achieve a successful WASH initiative. However, these last factors were not explicitly articulated in the CAWST theory of change. Additionally, it was found that these factors are all equally important, and a deep assessment of the contextual conditions of a community must be firstly undertaken to evaluate if some of them may require more attention than others. Additionally, it was found that WASH organisations must go through a process of understanding the societal norms, religion, traditions, and customs of the beneficiaries, so the project can be accepted and endure over time. Community participation and community empowerment through different approaches were also found to be key to deliver a successful WASH project. However, how the implementing organisations can engage with the community is an ad-hoc process depending on the contextual conditions of the beneficiaries. Therefore, it is of utmost importance that the organisation understands which approach will work in each context. A new revised theory of change was developed that includes community participation, environment, and sustainability as well as color-coding showing the degree to which WASH organizations consider the studied factors when implementing an effective WASH project. Further work must focus on evaluating other pathways in the CAWST theory of change that were not assessed in this study and developing a simplified theory of change in which it is clearly stated the factors on which CAWST has a direct influence.


Course Overview


The need to engage in better problem definition through careful dialogue with all stakeholder groups and a proper recognition of context.


An ability to work with specialists from other disciplines and professional groups acknowledging that technical innovation and business skills also must be understood, nurtured and combined as precursors to the successful implementation of sustainable solutions.


An understanding of mechanisms for managing change in organisations so future engineers are equipped to play a leadership role.


An awareness of a range of assessment frameworks, sustainability metrics and methodologies such as Life Cycle Analysis, Systems Dynamics, Multi-Criteria Decision making and Impact Assessment.