A five-member panel of water security experts cautioned public utility officers from around the country about ongoing physical, chemical and biological threats to public drinking water supplies and predicted new requirements for expanded water testing and monitoring.
The "Water Security Monitoring" panel was convened by Hach Company, a global source for aqueous analytical systems and solutions. The panel met Nov. 13 during the American Water Works Association Water Quality Technology Conference and Expo in Nashville, TN.
Panelists were questioned by audience members about potential threats and plans of action. The panel — including three consultants, an environmental program manager and a retired Center for Disease Control executive — underscored the importance of practical solutions including intensive and frequent water monitoring, physical security and emergency response plans in all water districts.
Michael Pikel, Environmental Programs Manager for the Philadelphia Water Department, said that something as simple as locating and exercising valves in the distribution system could aid in security. If contamination is detected in the system, being able to use valves to isolation portions of the system could stop the spread of a disease causing chemical or organism.
"Due to recent current events and threats to the nation's water supply, we are hosting this panel to raise awareness among water suppliers about the potential threats and how best to handle them," said Terry Engelhardt, a drinking water specialist with Hach Company in Loveland, CO. "Water systems of every size across the country need to be vigilant and prepared for deliberate attempts to contaminate water systems."
Audience members repeatedly expressed concern about the lack of guidance and clear direction from government agencies.
Referring to the oft-cited, "dilution is the solution to pollution," Dr. Irwin Pikus, a former member of the President's Commission on Water Systems Security, said, "This approach is valid for large sources, but far less so for other parts of the water distribution system. Regardless, it is important to be mindful of the severe psychological impact that even a relatively small incident can induce."
Panelists noted that promising new technologies to detect a wider range of potential contaminants are still several years from commercialization, and urge attendees to more frequently monitor traditional parameters to identify sources of contaminant threats.
Pickel talked about the City of Philadelphia's experience with hosting the National Republican Convention in 2000. The city worked with the FBI and Centers for Disease Control to set up a tracking system to detect sudden disease outbreaks that could be related to bio-terrorism.
The system monitored patient visits to first aid stations around the convention site and local hospital emergency rooms. Eight cases of gastrointestinal illness were identified, and six were investigated for potential bio-terrorism. No cases of bio-terrorism were identified, Pickel said.
After Sept. 11 the city set up the surveillance system again as an informal system.
The Philadelphia Water Department also has begun setting up a monitoring system to track such parameters as turbidity, pressure, conductivity, pH, chlorine and flow, Pickel said.
Anita Highsmith, Principal, Highsmith Environmental Consultants, Inc. and former head of the Water Quality Laboratory activities at the CDC, urged utilities to prepare an emergency response plan designed to deal with a terrorist attack. Her suggestions included:
- Stockpiling reagents and kits for water testing.
- Reviewing and updating Standard Operating Procedures
- Developing an employee handbook on safety and health
- Providing employee training on dealing with disasters
- Ensuring all indicator parameters are monitored on a periodic basis and any changes are recorded.
Pam Kenel, P.E., Senior Water Resources Engineer, Black and Veatch, emphasized the need for regular and detailed water monitoring.
"You are trying to detect patterns and trends, changes in water quality," she said. "Water quality changes seasonally and even diurnally. If you know what happens in your system over time, then you are more able to identify when something is unusual."
Parameters to monitor include pH, temperature, conductivity, phosphorous, nitrogen, silica, and acid base reactions, among others, she said.
Dr. Pikus served on the President's Commission on Critical Infrastructure Protection (PCCIP), where he led a focused team of other commissioners and staff in analyzing the threats to and vulnerabilities of the nation's water supply systems. The Commission was the first high-level group to identify purposeful chemical and biological contamination of water supplies as an under-appreciated threat.
Pikus stressed the need for basic security around water facilities. The panelists agreed that such common-sense measures as locks and fences, employee badges and security monitoring systems are a must.
"Have a specialist in security come out and walk through your facilities and look at all sites to give an independent assessment of what your vulnerability is," Pikus he said. "Then you have to see what you have to invest to mitigate the risk."
Security Monitoring TipsKnow Your Normal ValuesComparing current values against a normal baseline lets you identify the significant deviation or shift that signals an abnormal situation. The amount of data you need to establish a reference baseline depends on the normal variability of your influent water.
Consider Discrete Sampling
An automatic sampler that collects discrete samples on a regular basis allows you to isolate a sample from the time frame when a deviation occurred. With this sample you can then perform advanced analysis with GC-MS, AA, or ICP as needed.
Use Post-effluent Monitoring
Perform indicator tests at critical post-treatment nodes of your system, such as pumping stations, storage facilities, and the distribution system, or collect scheduled samples from these locations for lab analysis.
Maintain Adequate Chlorine Levels
In general, it's a good idea to make certain that residual chlorine levels in finished water and in the distribution system are held at prudent levels (check with your local regulatory bodies for specific recommendations). Monitor effluent with an on-line instrument for the most timely information, and consider increasing measurement frequency in the distribution system using an efficient field screening test.
Testing Methods
Total Organic Carbon (TOC) — working from an established reference baseline, this is an effective test for detecting contamination from organic compounds.
Biochemical Toxicity Test — measures adverse biological effects on a test organism. Use to screen influent stream for potential hazardous contamination.
Dissolved Oxygen (DO) — detects decrease in dissolved oxygen when a contaminant causes an increase in oxygen demand.
Chemical Oxygen Demand (COD) — measures the oxygen equivalent of organic matter content.
pH and/or Conductivity — detects change in water properties due to dissolved substance, serves as an early indicator of change from an established baseline.
