Grantee Research Project Results
Contamination Risk Assessment for Hurricane Damaged Water Distribution Systems
EPA Grant Number: FP917359Title: Contamination Risk Assessment for Hurricane Damaged Water Distribution Systems
Investigators: Piaskowy, Sara A
Institution: The Johns Hopkins University
EPA Project Officer: Packard, Benjamin H
Project Period: August 1, 2012 through July 31, 2014
Project Amount: $126,000
RFA: STAR Graduate Fellowships (2011) RFA Text | Recipients Lists
Research Category: Academic Fellowships , Fellowship - Drinking Water
Objective:
The objective of this project is to understand and model the risk of exposure to contamination from intrusion events caused by hurricane damages. This risk assessment then will be applied to evaluate policy intervention alternatives for reducing exposure to contamination.
Approach:
Achieving the goals of the research requires a three-prong approach. The first approach is to develop a model for predicting hurricane damages to water distribution systems. This will be done through analysis of historical hurricane records. Second is to study the volume of contamination intrusion due to pressure transient events. This will be done with controlled laboratory experiments and the results of which will be used to create a field-based data collection experiment to document intrusion in a real system. The final approach will be to develop a simulation-based contamination risk model for a hurricane damaged water system. This risk model will incorporate the results from the experimental phase, running simulations under various scenarios to observe differences in contamination risk.
Expected Results:
This work expects to find patterns of water system damages resulting from hurricanes that can be explained by characteristics of the water system or characteristics of the hurricane. At present, knowledge of water system damages from hurricanes is locally held. This work will likely find similarities across experiences and seek to determine the most important forces when considering water system performance in hurricanes. This work also expects to find that during a pressure transient, depending on the duration and intensity of pressure drop, there will be a detectable increase in turbidity and decrease in chlorine residual. Finally, with respect to risk assessment this study expects to find that greater and more frequent pressure transients will result in greater contaminant intrusion and increased threat to public health.
Potential to Further Environmental / Human Health Protection
This work has the potential to fill a key knowledge gap. At present, there is evidence that pressure transients occur regularly in a water system and that during a pressure transient intrusion of surrounding soil occurs. The missing point here is to understand to what degree is water quality affected by a pressure transient intrusion. If water quality is shown to degrade significantly as a result of a transient, policies could be put in place to reduce the occurrence of pressure changes or notify affected households and suggest they buy bottled water or boil water during the time when the pressure change might occur. Understanding the contamination effect of pressure transients could help develop new practices that will be more protective of water quality during the distribution phase.