Uncertainty-based flood resiliency evaluation of wastewater treatment plants

Abstract

Wastewater treatment plants (WWTPs) have a significant role in urban systems’ serviceability. These infrastructures, especially in coastal regions, are vulnerable to flooding. To minimize vulnerability, a better understanding of flood risk must be realized. To quantify the extent of efforts for flood risk management, a unified index is needed for evaluating resiliency as a key concept in understanding vulnerability. Here, a framework is developed to evaluate the resiliency of WWTPs in coastal areas of New York City. An analysis of the current understanding of vulnerability is performed and a new perspective utilizing different components including resourcefulness, robustness, rapidity, and redundancy is presented to quantify resiliency using a multi-criteria decision-making (MCDM) technique. To investigate the effect of certain factors of WWTPs on resiliency, uncertainty analysis is also incorporated in developing the framework. As a result, rather than a single value, a range of variation for each WWTP's resiliency is obtained. Finally, improvement of WWTPs’ performance is investigated by allocating financial resources. The results show the significant value of quantifying and improving resiliency that could be used in development of investment strategies. Consideration of uncertainty in the analysis is of great worth to estimate the potential room for improvement of resiliency of individual WWTPs.

Linking Water Infrastructure, Public Health, and Sea Level Rise: Integrated Assessment of Flood Resilience in Coastal Cities

“…To apply an integrative perspective, we operationalized key concepts to enable participating communities to assess hazard exposure and identify risks. “ Exposure ” to a given coastal threat is operationalized as a quantitative measure of assets, infrastructure, or population where a coastal flood may occur, a necessary first step to quantifying resilience (Karamouz et al, 2016). We defined “ Susceptibility ” as the degree to which a system is open, liable, or sensitive to climate stimuli, like sensitivity, with connotations toward damage and/or disruption or reduced level of service or function (cf.…”

“…Water utility and wastewater treatment systems may have storage systems, pipes, and pump stations that flood or fail owing to increased salinity of marine flooding and groundwater salinization (Flood & Cahoon, 2011). Although studies at a regional and national scale are informative to the scope of the problem (Heberger, Cooley, Herrera, Gleick, & Moore, 2011; Karamouz, Rasoulnia, Zahmatkesh, Olyaei, & Baghvand, 2016), the nexus of the threats to water supply and wastewater infrastructure and public health susceptibility in coastal cities invites the study and synthesis of a comparative, integrated assessment. In addition, cities that are prone to sea level rise owing to low-lying elevation and/or subsidence should also be investigated for interacting and cumulative risks arising from future conditions of tidal flooding, storm surges, extreme rainfall, and groundwater elevation.…”

A Group Decision-Making Model for Wastewater Treatment Plans Selection Based on Intuitionistic Fuzzy Sets

“…Maryam, Mohd Bakri, Ali, Latifah, Normala and Jamal (2017) proposed a method of steel-based waste water treatment technology using multi-criteria decision making and fuzzy logic. Karamouz, Rasoulnia, Zahmatkesh, Olyaei and Baghvand (2016) proposed a framework to evaluate the resiliency of Wastewater treatment plans in coastal areas of New York City. A MCDM model based on AHP was implemented to find the best alternative for solving wastewater in Iran (A. Hadipour, Rajaee, V. Hadipour, & Seidirad, 2016).…”

Comprehensive Flood Risk Assessment for Wastewater Treatment Plants under Extreme Storm Events: A Case Study for New York City, United States

“…Because these WWTPs are in the coastal area of NYC, they are more susceptible to sea level rise. Strom surges are another concern for wastewater plants and are mainly caused by strong winds in hurricanes or tropical storms [20][21][22]. The frequency of hurricanes is accelerating, and the losses caused by them are becoming ever more severe.…”