Monitoring water distribution systems

To monitor the nitrate and nitrite levels in water treated with chlorine and ammonia, water samples must be obtained regularly from water distribution systems and plant process sites and taken to a laboratory for analysis. 

Temperature indicators are used to monitor the temperature continuously. The temperature requirement for the WFI tank is >85°C and for the water distribution system >80°C. Conductivity... 

Environment Sensors monitoring air and water quality will be able to provide early warning of pollution events arising at industrial plants, landfill sites, reservoirs, and water distribution systems at remote locations. The environmental nervous system concept likens the rapid access and response capabilities of widely distributed sensor networks to the human nervous system that is, it is able to detect and categorize events as they happen, and organize an appropriate response. 

Nitrite has a similar action to nitrate, but is usually only found at very low concentrations. It is sometimes formed in water distribution systems when monochloramine is used as a residual disinfectant. Nitrite and nitrate need to be considered together, but monitoring for nitrite is difficult because formation will be in the distribution system. Nitrate levels in surface waters can change quite quickly, but levels in groundwater usually change very slowly unless the groundwater is heavily influenced by surface water. 

Fire water distribution systems including hydrants, monitors, etc. 

In the first case of interacting systems, we should determine all other systems that may have even occasional impact on our system. For example, if the transportation system in Fairfax, Virginia, the United States, is considered, it can be determined that the power system and the water distribution systems will interact with our transportation system. (Obviously, we could find more systems interacting with our transportation system in Fairfax.) The power system provides power to all signals and monitoring devices, and this is a positive impact. The power system may fail, and this will be a... 

Water supplies are closely monitored for heavy metals, because they tend to be very toxic. Major sources of heavy metal contamination include landfills, industries, agriculture, mining, and old water distribution systems. 

Cantor, A.F. (2009). Water distribution system monitoring. CRC Press. 

BEWS applications include monitoring of drinking water intakes, water distribution systems, wastewater effluents, effluents from crmtamination sites, or river basin monitoring, and provide a rapid evaluatiOTi of water quality and toxicity that cannot be achieved through other analytical methods. 

When water is combined with other additives, it can control and extinguish most petroleum fires. A water suppression system consists of a supply source, distribution system, and the end using equipment such as fixed spray systems, monitors, hose reels and hydrants. The objective of water suppression systems is to provide exposure cooling, fire control, suppression of fire incidents and may assist in the dispersion of flammable or toxic vapors. 

In 1966 and 1967, when the use of endrin was not restricted, endrin was detected in 5 of 67 raw water samples from the Mississippi and Missouri Rivers (Schafer et al. 1969). At a later time when endrin use was substantially restricted, an Iowa study of 33 community water supplies using surface water found no detectable concentrations of endrin in the distribution systems (Wnuk et al. 1987). In an extensive water quality monitoring program conducted by the California Department of Health Services, endrin was detected (detection limit not specified) in only 2 of 5,109 public drinking water sources sampled from 1984 to 1992, at mean and maximum concentrations of 0.06 and 0.10 ppb, respectively (Storm 1994). Concentrations did not exceed the Maximum Concentration Level (MCL) of 0.2 ppb. In another recent study, endrin was not detected (detection limit not specified) in 32 samples each of raw water and highly treated reclaimed waste water undergoing evaluation as a possible supplement to raw water sources in San Diego, California (De Peyster et al. 1993). 

The existence of a guideline or standard achieves nothing unless it is enforced. This situation implies a need for monitoring and surveillance activities. It is of prime importance that every effort be made to ensure that water quality guidelines are met and that water quality is maintained throughout the distribution system. 

Fluoride can also be removed from a centralized water treatment point. This is common in developed or countries in economic transition and provides a longterm solution to fluoride problem in drinking water. A full-scale water purification plant based on AA-adsorption media was reported to be in operation in Kansas, USA. In this technique, all water to the distribution system is treated irrespective of its intended use. Thus, it is unrealistic way of defluoridating water since the main concern is usually fluoride ions contained in drinking water. From the technical point of view, however, centralized water treatment guarantees the quality of drinking water since the performance of the defluoridation plant can easily be monitored. Wider application of this technique for the sole purpose of removing fluoride from water is not widely reported in literature. 

The most widely used metal for pipes and fittings in distribution systems is iron, which may give rise to corrosion products. These products can cause discolouration at the tap if the distribution system is not managed correctly. Monitoring for corrosion products is not appropriate instead, it is necessary to manage the problem of corrosion and the accumulation of corrosion products in distribution. In some circumstances, iron hand pumps can give rise to discoloured water if they are corroded by water that is too acidic. In such cases, it may be appropriate to... 

Ammonia is occasionally found in distribution systems where chloramine is used as a residual disinfectant, if the process of producing chloramine is not sufficiently well controlled. Monitoring could be carried out in the final water from the treatment works, but other parameters (e.g. free chlorine) are normally considered to be more important. 

Disinfectants are usually only monitored to ensure that disinfection has taken place. Certain disinfectants, such as chlorine, are sometimes monitored at the tap or in the distribution system, as a measure of the quality in distribution. A wide range of potential by-products of disinfection may be formed in treatment, particularly if natural organic matter is present at high concentrations. The most commonly monitored by-products are the trihalomethanes (THMs) formed through chlorination THMs are normally considered to be an adequate marker of the total disinfection by-products from chlorination. Some countries also monitor haloacetic acids, but these are difficult and expensive to analyse because of their high polarity. Bromate is sometimes measured when ozone is used, but its formation relates to bromide concentrations in the raw water and the conditions of ozonation. Analysis can be extremely difficult and monitoring is not usually considered except where standards have been set or on an infrequent basis. 

Since switching to postchloramination, the utility has experienced no adverse effects in operations or in finished water quality. According to distribution system monitoring records, the microhiological quality of the water has been maintained. 

Wherever water ean be drawn from the distribution system, it would be possible to use a pump to injeet material baek into the system. Once the contaminant is present in the pipes, the normal movement of water in the system acts to disseminate the contaminant throughout the network. The introduction point can be anywhere in the system. Due to the vast expanse of the distribution network, physically securing the system against such attack becomes impossible. That leaves monitoring as the only viable method to protect against such events. 

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