Drinking water distribution

Niquette P, Servais P, Savoir R (2001) Bacterial dynamics in the drinking water distribution system of Brussels. Water Res 35(3) 675-682... 

Koskinen R, Ali-Vehmas T, Kampfer P et al (2000) Characterization of Sphingomonas isolates from Finnish and Swedish drinking water distribution systems. J Appl Microbiol 89(4) 687-696... 

Blanch AR, Galofre B, Lucena F et al (2007) Characterization of bacterial coliform occurrences in different zones of a drinking water distribution system. J Appl Microbiol 102(3) 711-721... 

Rigal, S. and Danjou, J. (1999). Tastes and odors in drinking water distribution systems related to the use of synthetic materials. Water Sci. Technol. 40, 203-208. 

Tomboulian, P., Schweitzer, L., Mullin, K., Wilson, J., and Khiari, D. (2004). Materials used in drinking water distribution systems Contribution to taste and odor. Water Sci. Technol. 49, 219-226. 

Only one case reported an increase of Al during drinking water distribution (also discussed in this paper), because Al leached from the cement lining of a water distribution pipe [17, 18]. 

Cement linings of drinking water distribution pipes should be reevaluated for their possible toxicological properties. 

If a proportion of the water from the old well is too high, the mixed water shows sulfate and nitrate concentrations exceeding drinking water standards (bold), if it is too low, the mixture is calcite aggressive (bold), which may lead to pipe corrosion. The optimum ratio is between 40 60 to 60 40, where the water can be discharged to the drinking water distribution net without any further treatment. 

Some people may also be exposed to elevated levels of asbestos in drinking water, particularly where there are widespread natural deposits of asbestos (e.g., San Francisco Bay area), disposal of asbestos-containing ore tailings (e.g., Duluth, Minnesota), or the use of asbestos-containing cement pipes in drinking water distribution systems with low pH and low hardness (Craun et al. 1977 Kanarek et al. 1981 Webber et al. 1989). 

We can thus conclude that the amino acids do not represent a negligible part of the overall residual (10—30%). The amino acid release by filter in drinking-water may present a danger of bacterial proliferation in the drinking-water distribution system, since the carbon source is easily biodegradable. Such a hazard can be minimized by a superchlorination at the end of the treatment. However, previous [12, 13 ] and more recent [14, 15] research has shown that the action of sodium hypochlorite on ctamino acids rapidly leads to the formation of aldehydes and nitriles. Therefore, postchlorination only changes the problem to a more complex one. 

Major human exposure has been in the dry cleaning industry and in industries employing degreasing procedures. In addition, inhalation of contaminated urban air (especially near point sources such as dry cleaners), drinking contaminated water from contaminated aquifers, and drinking water distributed in pipelines with vinyl liners may offer additional exposure opportunities. 

The following items can affect microbial regrowth in a drinking water distribution system ... 

Unfortunately these sorts of statements apply only to large reservoirs and water sourees and not to the distribution system. Various industry experts soon pointed out the error of deelaring om water supply to be safe. Researehers from the US Air Force, Army Corps of Engineers and Haeh Homeland Seeurity Teehnologies (HST) have ealeulated that an attaek on drinking water distribution systems ean be moimted fro between 0.05 and 5.00 per death, using radimentary teehniques, and amass easualties in the thousands over a period of hours via a method known as a baekflow attack. " ... 

T. P. Allman, Drinking water distribution system modeling for predicting the impact and detection of intentional contamination. Masters Thesis, Colorado State University, Dept of Engineering, Fort Collins Colorado, Summer (2003). 

Sly LI, Hodgkinson MC, Arunpairojana V. 1988. Effect of water velocity on the early development of manganese-depositing biofilm in a drinking water distribution system. FEMS Microbiol Ecol 53 175-186. 

STUDY OF BIOFILM FORMATION ON DIFFERENT PIPE MATERIALS IN A MODEL OF DRINKING WATER DISTRIBUTION SYSTEM AND ITS IMPACT ON MICROBIOLOGICAL WATER QUALITY... 

Abstract. The biofilm formation in drinking water distribution systems depends on many factors and may cause a number of technological and hygienic problems. In this study, the influence of pipe material and flow velocity on the biofilm growth dynamics and its impact on microbiological water quality in a model of drinking water distribution system were assessed. 

Keywords biofilm drinking water distribution system microbiological water quality... 

Biofilm study was carried out in the drinking water supply system DWSS"Yovkovtsy , that supply with water the region of Veliko Tamovo, and in the laboratory model of water distribution system. Some experiments were performed 1) to determine microbiological composition of biofilm samples scraped from mild steel or reinforced concrete s main pipe line and concrete tank of DWSS Yovkovtsy 2) to study biofilm formation process on test pipe from PVC, PE, stainless steel and carbon steel in a laboratory model of drinking water distribution system under flow velocity 0,006 cm/s. 3) to study dynamics of biofilm formation process on polypropylene, the pipe material used during the last years in Bulgaria, in a model water distribution system under flow velocities 0.3 m/s, 0.5 m/s, 0.7 m/s and 1 m/s. 

FIGURE 1. Bacterial density of biofilms developed on main pipe lines from carbon steel (1,2) or reinforced concrete (3,4) and concrete tank (5,6) in drinking water distribution system Yovkovtsy , domestic installation from galvanized steel (7,8) and test surfaces from stainless (9) or carbon steel (10). 

Niquette, P., P. Servais, R. Savoir, Impacts of Pipe Materials on Densities of Fixed Bacterial Biomass in a Drinking Water Distribution Systems of Brussels, Wat.Res., 2000, Vol. 34, N 6, pp. 1952-1956. 

EVALUATION OF BIOFILMS OCCURING IN DRINKING WATER DISTRIBUTION SYSTEM OF BALATONFURED... 

Samples were collected from eight fire hydrants of drinking water distribution net on three separate occasions, in May, July and September, 2004 (see Results and discussion). Before filling bottles we have opened fire hydrants to maximum rate of flow for two minutes to flush off biofilms from the walls of pipes and to aviod stagnant water sampling. 

What are the main steps in treating raw water for drinking water distribution systems in Asia Do all of them need to be applied ... 

Drinking water must have an acceptable taste, it should have good appearance, it should be free from unpleasant odour and it should also have an appropriate temperature so that it is refreshing. Drinking water distribution through pipelines should not worsen its quality. The requirements for a sufficient quantity of drinking water result from the aspects of hygiene [7-12]. 

The possibility of contamination of the distribution system by microbial aftergrowth was suggested in the literature a.s far back as the 1920s [48] but the problem received more attention in the early 1970s when certain principles from microbial ecology were adapted and applied to drinking water distribution systems [16]. 

Gauthier V., Gerard B., Portal J.-M., Block J.-C., Gatel D. (1999), Organic matter as loose deposits in a drinking water distribution system. Water Research, 33, 4, 1014-1026. 

In solution, HOCl and hypochlorite concentrations are commonly determined together by standard water analysis methods (AWWA, 1989). The sum of their concentrations is referred to as free available chlorine and is usually reported in parts per million (1 ppm free available chlorine = 1.4x 10" M). Detectable levels of free and combined (nitrogenous) available chlorine in treated water constitute a chlorine residual. In normal practice in North America, water utilities attempt to adjust chlorination levels to a small chlorine residual (2x 10" M or less) that is sufficient to survive throughout the drinking water distribution system all the way to the user s water taps. To achieve this level in the distribution lines, it may be necessary to add as much as 10 times higher amounts to the water in the plant, depending on the amount of reactive material in the source water and in the lines. 

MIC has also been documented for copper and copper alloys used in potable water applications. Alanis and coworkers [36] described a case of localized corrosion in underground brass pipes of low zinc content (8.22%) used for drinking water distribution. Perforation was due to SRB... 

D.A. Lyde, M.N. Nadagouda, A comprehensive investigation of copper pitting corrosion in a drinking water distribution system, Corros. Sci. 52 (2010) 1927—1938. 

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