A new advanced contamination warning system (CWS) for water treatment systems has been demonstrated in a series of projects across the country. The CWS draws on multiple, disparate data streams that can enable utility managers to quickly identify when something unusual occurs within their water distribution systems, and help them discern when the situation is a cause for concern. Wikimedia Commons/ James T. M. Towill
A series of white papers published recently highlight an EPA pilot project that reveals that water contamination warning systems can pay for themselves quickly and offer many side benefits.
August 27, 2013—The Philadelphia Water Department (PWD) and consulting engineering firm CH2M HILL, of Englewood, Colorado, recently released a series of white papers detailing the best practices gleaned from a 4 ½-year demonstration project of an advanced contamination warning system (CWS) for water treatment systems. Originally envisioned as a means to quickly detect and respond to the intentional introduction of contaminants, the systems have proven to have valuable applications in everyday situations as well.
The PWD project was part of a larger, three-phase program funded by grants ranging from $8.5 to $12 million from the U.S. Environmental Protection Agency (EPA) under the Water Security Initiative (WSI) program. The WSI developed as a result of the vulnerability assessment processes conducted in the aftermath of the terrorist attacks on September 11, 2001, says Ken Thompson, the deputy director of intelligent water solutions for CH2M HILL.
“The distribution systems seemed to be the big black hole out there; there just wasn’t a lot of information available to utilities to understand when something unusual happened,” Thompson explains. The initial pilot project was conducted in Cincinnati by the USEPA Water Security Division. On the basis of the results from the Cincinnati project, the EPA provided grant funding for four demonstration projects in Philadelphia, New York City, San Francisco, and Dallas; CH2M HILL was a consultant for all of them.
The CWS system developed from this program draws on multiple, disparate data streams that can enable utility managers to quickly identify when something unusual occurs in the system and help them discern when the situation is a cause for concern.
“The data streams that all the utilities looked at include online water quality [from] monitoring, customer complaints, public health [reports], and physical security,” Thompson says. “They also developed an extensive sampling and analysis program for collecting baseline data in the system, as well as responding to an event.”
Once entered into the CWS system, the data is analyzed in real time. If a parameter exceeds thresholds developed by the utilities based on their baseline data, it is brought forward as an alert. All four utilities developed a dashboard as part of the demonstration pilot that spatially displays information from the data streams.
Some indicators, such as consumer complaints, are leading indicators of a problem. Other indicators, such as public health reports, develop over time and are used as a confirmation tool.
“What we found is when you started merging these multiple data streams together, one plus one didn’t equal two—it equaled three or four or five,” Thompson says. “It was much more powerful because you had validation of something unusual happening because you had information from the disparate data streams coming together, indicating the same thing.”
The dashboards display information in a manner that enables utilities to make connections between, for instance, a spike in customer complaints about water quality and unusually high reports of illnesses at local hospital emergency rooms. The utilities then look for connections and consider operational issues—such as line flushing or an algae bloom—that might have caused an unusual occurrence in the system in that area, that day.
In the pilot studies, if utilities went through that process and couldn’t identify a likely cause, this triggered a tiered response process, each tier indicating that a contamination event was increasingly likely to have occurred. Higher tiers triggered a higher level of response, communication, and coordination with other agencies.
The system monitors for contaminants in five broad groups: industrial chemicals, chemical warfare agents, microbial agents, biochemical agents, and radioactive materials. The online water quality monitoring (OWQM) units detect changes in conductivity, combined or free chlorine, pH, oxidation-reduction potential (a measure of the effectiveness of sanitizers), temperature, turbidity, total organic carbon, and the absorption of ultraviolet light at the 254‐nanometer wavelength.
“Because the number of potential contaminants is large, many cannot be specifically identified through conventional OWQM monitoring,” the reports note. “Thus, it is typically more practical to use sensors that measure indicator or surrogate parameters to detect abnormal water quality for possible contamination evaluation.”
Although CWS techniques were originally developed for security, the pilot programs have revealed them to have tremendous operational benefits. By carefully monitoring even minor water contaminants in the distribution system and analyzing the data in real time, utilities can develop a much clearer picture of how the system is operating.
“I worked for utilities for 20 years prior to joining CH2M HILL,” Thompson says. “On the utility side, we rarely processed and analyzed more than 30 percent of our data and developed it into ‘actionable information,’ due to staff availability. As an example, in one of the water-quality stations, we collect about 1 million data points a month and that is processed behind the scenes. The utilities now have availability of information and knowledge from that data without having to spend a ton of staff time to produce it.”
The information gleaned from the systems can be exceptionally valuable. The monitors can detect changes in the system itself—unusual corrosion in the pipelines, for instance, that could point to a pending failure or deterioration of the system, or changes in the characteristics of source water that might need to be accounted for in the treatment process.
“Using this information, the utilities are able to start to focus on where their limited capital dollars should be placed rather than trying guess,” Thompson says. “They have been able to gain a ton of new insight from the multiple data streams. Dual benefits are what we hoped for and it’s definitely been demonstrated to be true. It would be hard to fund a system for just security alone in this day and age, [when] utilities have so many demands on their limited dollars. Through the implementation of these projects, utilities will receive a cost savings for the operation side of the business, which provides the incentive to move forward. The CWS projects have provided the industry with the basic integrated water-quality structure for a ‘smart grid’ for their water systems.”