Surveillance Data

Water testing data are collected based on federal, state, and local regulations. The tests performed, and their frequencies, vary with the site being tested. For example, New York City has a water surveillance program (Heffernan et al., 2004), and strict guidelines for comprehensive watershed monitoring program (New York City Department of Environmental Protection, 2005a). Tests include, but are not limited to, raw fecal coliform levels and biologicals such as Cryptosporidium and Giardia species. Raw fecal coliform reservoir levels must be fewer than 20 colonies per 100 ml sampled, in greater than 90% of measurements during any 6-month period (New York City Department of Environmental Protection, 2005b). The samples are collected from various locations, including dams, intakes, mid-reservoir points, and main tributaries. The program has close to 1,000 sampling areas, and calls for more than 1,300 water samples per month from many of these sites. Public watershed information is available online, including the diagram in Figure 9.5, showing part of the New York City/ Catskill Watershed.

In New York State, water samples expected to contain select agents, are sent to the Biodefense Laboratory of the State DOH for analysis. The New York State DOH performs all detection and identification of select agents, and provides extensive training to the hazardous situation first responders, such as fire and police officials, providing guidelines for sample collection, aiding in incident response, and building a feedback loop for communication. This next section details an actual timeline of select agent analysis associated with a security breach at a New York City water reservoir. Workers at a municipal water system notified the New York City DEP at 10:30 a.m. to report the presence of a suspicious bottle near the edge of the water supply. The bottle was a large plastic soda bottle, which was covered in brown tape and partially filled with a dark liquid. The bottle contained noticeable par-ticulate matter and was found with two pieces of paper. The responding officer inspected the scene and called in the DEP"/>
FIGURE 9.5 A depiction of the Catskill/Delaware Watersheds serving New York City. (From the New York City Department of Environmental Protection,

hazardous materials (hazmat) responders. The hazmat team performed a test for explosives (none identified) and notified the DOH Biodefense Laboratory of the sample at 2:30 p.m. The hazmat team transferred the material to a container for transport and chain of custody to the DOH laboratory, departing at 3:30 p.m. Material to be tested arrived at the laboratory at 6:50 p.m., and DOH preliminary testing returned negative for the presence of ricin toxin and B. anthracis by 11:30 p.m. Additional preliminary analysis for Yersinia pestis, Francisella tularensis and Brucella species was determined to be negative by 9:15 a.m. the following morning. Negative culture analysis for the above select agents was confirmed approximately 48 hours from receipt of sample, and this initiated the transfer of the suspect material for chemical analysis. The water in the reservoir, which was to enter the distribution chain in 1 week, was evaluated for further contamination. This incident highlighted a number of issues:

• The importance of communication between state agencies and local entities, to provide a comprehensive and rapid response to a potential bioterror incident. Although this incident was not found to involve hazardous chemicals or biological agents, it served an exercise of the response system in New York State. • The value of further accelerating and streamlining the data collection, analysis, and response process. Although the water in this case was not scheduled for release that day, the utility's managers would have been fully justified in following EPA guidelines and isolating the water tank immediately after discovery of the plastic bottle but before tests were complete. This does not mean the utility reacted inappropriately in this case, but rather, a different water distribution schedule would have mandated a swifter containment response.

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