Real-Life examples of Water quality events detected or operations being optimized with GuardianBlueR Event Detection System or Hach’s other distribution monitoring solutions.
PDF Success Stories:
- Clear Lake Application Article [pdf]
- HST On Guard Newsletter #2 [pdf]
- HST On Guard Newsletter #1 [pdf]
- JAWWA 2008 Olympics Article [pdf]
- North Wales WDMP Article [pdf]
- Real Water Events Presentation [pdf]
- Real World events White Paper [pdf]
- Ammonia Overfeed [pdf]
- Water Security Monitoring at Beijing Olympics – World Health Organization (WHO) [pdf]
Road Work Event Caught in Real-Time
Road work near a distribution line dislodged biomass and other particulate matter from the lining of the pipe. There was a massive increase in turbidity, which not only showed up on the turbidimeter, but also showed up as an interference in the chlorine measurement (optical ). As expected, the conductivity and pH also showed minor changes. The increase in biomass in the water was indicated by the TOC analyzer. This event illustrates the ability of the Event Monitor to detect and alarm on unanticipated events. This event also provides a signature for the materials adhering to the walls of the pipes in this location.
Eight inch Pipe Break
The break occurred on June 29th. The pipe was an 8” line and located 1.8 miles away from the WDMP. There was an increase in turbidity and chlorine. Turbidity appears to have increased the day before the break.
36 inch Pipe Break Alarmed Almost Three Days Before Event
Did you know the GuardianBlue system alarmed almost three full days before a catastrophic pipeburst and has detected pipeburst events in many major US cities? It’s true, using its’ unique algorthim with regularly monitored parameters, GuardianBlue saw a change in both conductivity and chlorine at the same time. Normally these particular changes are considered small enough and are not detected by the human eye, but the algorithm caught the deviation and started alarming about 70 hours before a 36″ main broke, spilling millions of gallons of water into downtown. The pipe had a small crack, which is why the conductivity and chlorine changed, due to decreased water age. About 3 days later, the catastrophic break occurred. The instrumentation was 2 miles upstream from the break. This particular municipality can name this event in the Plant Library, and should it see a similar fingerprint, the event monitor would recall the name given in the Plant Library. The EPA estimates the average pipebreak costs about $29 million dollars in repair and lost revenue.
Faulty Check Valve Discovered
In one Northern Midwest system, every Friday, the sensors would behave extremely erratically resulting in multiple alarm signals being generated. Investigations led to the discovery of extreme amounts of entrained air bubbles being present in the systems water on Friday afternoons and evenings.
Further investigation revealed that school buildings that were to be vacant over the weekend had a policy of using air to blow out their water lines to prevent freezing so that the heat could be turned off over the weekend. A faulty check valve at one of the schools allowed the air to bleed into the distribution system. The valve was replaced, thus closing a possible backflow route into the system. After this the erratic readings ceased.
Flushing Schedule Optimized
A drinking water facility on a military base kept getting phone calls from consumers of their water who were complaining of a funny taste and odor. Each time a complaint was called in, a drinking water plant operator would drive to a water sampling point in the distribution system and test the water. After several unsuccessful attempts at trying to figure out the cause of the odd water and persistent complaints, a series of water distribution monitoring devices were purchased and installed. These devices monitored the water quality on a continuous basis and therefore made it easier to respond and correlate the poor water quality to the complaints. They discovered low flow areas and dead heads within the distribution system. With this new information in hand, the plant operators optimized their flushing schedule and greatly improved the water quality resulting in no more complaining phone calls.
Grab Sample vs On-Line Case Study
Customer performed extensive grab sampling and believed water quality to meet all of their standards, and the water quality did meet the standards during the grab sampling tests. They installed several WDMPs at key locations around the city and found turbidity spiked to 20 NTU at night and high variability of Cl2 levels. The municipality changed their processes to minimize spike to about 1.5 NTU at night. Result: Improved Water Quality and Consistency.
Water Mapping Case Study
This municipality has many WDMPs out in their distribution system. Three water plants serve the area, mixing water from all three plants. They discovered conductivity is a valuable parameter to trace where water is going and aid in hydraulic mapping. This municipality also used the chlorine readings for the reporting purposes. Understanding your hydraulic map offers many benefits such as scheduling repairs, planning for growth and identification of system deficiencies. From another point of view, one can predict where the ‘bad’ water is moving to and what populations it will affect first.
Operational Mistake Case Study Customer received incorrect concentration of caustic chemical to feed and did not notice Added usual amount to distribution system resulting in caustic overfeed WDMP with Event Monitor alarmed – notifying customer of adverse conditions Corrective actions put in place to prevent future operational mistakes of this kind Result: Improved Water Quality.
Fluoride Overfeed Caught in Real-Time
The water distribution system can be vulnerable to accidental exposure to unwanted water quality events. In this real-life scenario, the water utility was forced to revert to the utilization of a different water treatment plant while maintenance was being done to the new plant. A pump responsible for dosing fluoride into the treated water malfunctioned causing the dose to increase over time. When the overdose occurred, the GuardianBlue Early Warning System not only alarmed but also classified the likely cause of the problem to be a fluoride overfeed. This allowed a rapid response before consumers of water were exposed to potentially dangerous levels of fluoride. Fluoride, while toxic at moderate to high doses, is generally considered beneficial for dental health at low doses. The most commonly recommended dosage of fluoride for humans is 1 mg per day.