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Abstract Uncertainty arising from climate change poses a central challenge to the long‐term performance of many engineered water systems. Water supply infrastructure projects can leverage different types of flexibility, in planning, design, or operations, to adapt infrastructure systems in response to climate change over time. Both flexible planning and design enable future capacity expansion if‐and‐when needed, with flexible design proactively incorporating physical design changes that enable retrofits. All three forms of flexibility have not previously been analyzed together to explicitly assess their relative value in mitigating cost and water supply reliability risk. In this paper, we propose a new framework to evaluate combinations of flexible planning, design, and operations. We develop a nested stochastic dynamic optimization approach that jointly optimizes dam development and operating policies under dynamic climate uncertainty. We demonstrate this approach on a reservoir project near Mombasa, Kenya. Our results find that flexible operations have the greatest potential to reduce costs. Flexible design and flexible planning can amplify the value of flexible operations under higher discounting scenarios and when initial infrastructure capacities are undersized. This approach provides insight on the climate change and techno‐economic conditions under which flexible planning, design, and operations can be best leveraged individually or in combination to reduce climate change uncertainty risks in water supply infrastructure projects.
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Reconciling complexity and deep uncertainty in infrastructure design for climate adaptation
As climate change is emerging as a major challenge for man-made systems in the coming century, there has been significant effort to understand how to position infrastructure to adapt and deliver services reliably. Particularly, the climate is changing faster than the expected lifetime of critical infrastructure, resulting in situations well beyond the intended design conditions of a stationary climate. This study assesses how well existing infrastructure design approaches – traditional fail-safe, armoring, low regret, safe-to-fail, and adaptive management – account for climate-related complexity and uncertainty through an application of the Cynefin and Deep Uncertainty Frameworks. The results indicate that existing infrastructure design approaches have varying levels of validity for addressing climate change across spatial and temporal scales. The most common infrastructure design approaches undertake lower levels of complexity and uncertainty than climate change demands, indicating the potential of approaches that address complexity and deep uncertainty have not been fully realized. KEYWORDS: Climate change, infrastructure, deep uncertainty, complexity, adaptation
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- PAR ID:
- 10171435
- Date Published:
- Journal Name:
- Sustainable and Resilient Infrastructure
- ISSN:
- 2378-9689
- Page Range / eLocation ID:
- 1 to 17
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1080/23789689.2019.1708179
