Enhancing Water Security: EPA Prepares for Intentional Contamination Incidents
EPA scientists make a variety of tools available to drinking water managers to help them keep water safe and secure.
While most people never give a second thought to opening their drinking water tap , public and private water utility managers remain vigilant to ensure the safety and security of the nation’s water supply as it flows from source to sink.
Since 1998, EPA’s mission included protecting the nation’s water supplies from terrorists who might use chemicals, biological agents, or radioactive materials as poisons. Following the events of 2001, EPA was also designated as the primary federal agency responsible for decontamination in the event of such an attack. Agency scientists have continued developing and piloting new technologies to help water utilities prevent, detect, respond to, and recover from such drinking water contamination events.
A significant advance in protecting drinking water distribution systems has been the development of network based detection systems for use in complex drinking water systems. “One of the challenges is that there are so many contaminants of concern,” says Regan Murray, Ph.D., of EPA’s Water Infrastructure Protection Division. Typically, a utility monitors water quality by taking periodic samples and analyzing them in a laboratory for regulated contaminants such as lead and copper. Sampling intervals vary from once a day to, in some locations, once a month. Ideally, a utility would install automatic sensors that monitor water quality continuously. EPA is working to make that possible, starting with pilot projects in several cities.
Recognizing that any early warning system would need to cover large systems and be affordable to utilities, EPA focused its research on investigating effective, practical technologies for wide-spread use. Researchers evaluated a variety of commercially available sensors and instruments to identify technologies that could be used to detect changes in baseline water quality. These baseline changes, detected early through real-time monitoring, can alert water utility operators of potential contamination and the need for further sampling and analysis.
EPA researchers reviewed a variety of sensors that measure broad indicators of water quality, such as pH, total chlorine, and total organic carbon (TOC). They discovered that existing technologies could be used to measure total chlorine and total organic content (TOC) as a way of detecting other chemical and biological contaminants from both accidental and deliberate (such as sabotage) events.
As you would expect, we have operations people - in our control center 24-hours a day, 365 days a year. They can feed data into a computer, and if contamination is detected, an audible alarm will sound,” says Greater Cincinnati Water Works Assistant Superintendent, David Hartmann.
EPA’s pilot projects are part of the Water Security Initiative, a new effort to bring technological solutions to the challenge of monitoring contamination in major cities such as Cincinnati, Ohio—site of a full-scale, comprehensive pilot in partnership with the City of Cincinnati at the Greater Cincinnati Water Works.
One of the early success stories of the research is CANARY Event Detection Software, a technology that serves as an early warning system for water utilities to quickly distinguish normal variations in water chemistry from a potential contamination event. Developed in partnership with Sandia National Laboratories, CANARY was recognized as one of the top 100 new technologies of 2010 by R&D Magazine. EPA makes the software available for free.
Even the least expensive, commercially- available contaminant sensors are costly, typically $5,000 to $10,000. Therefore, to efficiently monitor their water distribution systems, utility operators must carefully choose the best locations for placing sensors . To help, EPA researchers also developed the Threat Ensemble Vulnerability Assessment-Sensor Placement Optimization Tool, which offers a user-friendly interface to guide water managers in optimally placing sensors across their distribution network.
EPA continues to innovate and develop other water security products, but these are “…still in the research stage,” says Murray. One example is EPANET-MSX, a software program that water utility managers can use to model the physical and chemical changes a contaminant might undergo as it flows through a system: dilution, reacting with chlorine, or sticking to pipe walls. Understanding these processes helps to identify the best way to decontaminate a system following a contamination incident.
Much as the space program led the development of technologies, like satellite TV, that have broad uses in daily life, EPA’s water security research has multiple benefits that address the everyday needs of water quality managers. The software Agency researchers are developing can be used to plan new infrastructure for expanded water service or respond to a water main break. “CANARY is useful because it doesn’t just help detect contamination that could be caused by a terrorist, it can also help to detect other water quality problems that might occur during normal operations,” Murray says.