By Dan Kroll
Monitoring is a critical component of any water security program. There is no other feasible way to address the severe vulnerability presented by the threat of an intentional contamination event. In an attempt to bring all of the various aspects of water security monitoring into a working system, the EPA has launched a pilot program to design and build such a system using off the shelf technology in a number of pilot communities. This program is called The Water Security Initiative.
Direct monitoring of water quality is not the only approach that is being investigated to provide detection and warning of an attack. Syndromic surveillance is a concept that comes originally from the medical profession. In the medical case, the term refers to surveillance using health-related data that precede diagnosis and signal a sufficient probability of a case or an outbreak to warrant further public health response. Though historically syndromic surveillance has been utilized to target investigation of potential cases in a disease outbreak, its utility for detecting outbreaks associated with bioterrorism is increasingly being explored by public health officials.
In the Homeland Security realm, as it pertains to water, syndromic surveillance is the concept of using advanced computational techniques and data mining algorithms to monitor a number of nonspecific indicators of a possible attack. These include such data as hospital admissions, 911 calls, pharmacy sales, and complaints to the utility. These data streams are directed to a centralized computing system that correlates all of the factors and extrapolates the probability of an attack using advanced algorithms. Once an attack has been indicated, appropriate response actions can be initiated to treat the potential victims.
Although much useful information could theoretically be extrapolated from such a monitoring program, there are severe drawbacks. Syndromic surveillance, by its very nature, is directed toward thwarting naturally occurring outbreaks of disease. The results of an intentional contamination event using water as a vector may spread quickly enough to make detection by such a mode redundant and unnecessary. Also, the reliance on such a mode of detection delays the reporting of the hypothetical event until actual exposures have occurred. This may be adequate in cases of bacterial contaminants that may have a fairly long incubation period and can be treated with antibiotics. It is, however, woefully inadequate in the case of a chemical or biotoxin contamination event.
By the time such an attack is detected via syndromic surveillance, it is too late to do anything to decrease the number of casualties and the damage incurred. The use of such technology as a stand-alone method becomes nothing more than a means to keep track of damage rather than to prevent it. Syndromic surveillance does have some merit when the stream of data being analyzed includes real-time water quality monitoring results. Recognizing this, the EPA is not relying solely on syndromic surveillance as some have advocated, but rather is using it as a supplement to water monitoring data.
With the current state of technology, there is no need for us to operate our water systems in the unsecured mode of the past. Admittedly, the instrumentation available today is not perfect, but it will show us a clear enough picture to avoid many of the hazards that we would surely encounter if we left the old paradigm in place.
About the Author: Dan Kroll is chief scientist at Hach Company's Homeland Security Technologies division, in Loveland, CO. He has been the lead researcher on a variety of method development projects for the physical, chemical and microbiological quality of water and soils for which he holds several patents.
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