The sustainable development assessment of drinking water supply system/Geriamojo vandens tiekimo sistemos darnaus vystymo vertinimas.
Valentukeviciene, Marina ; Ignatavicius, Gytautas ; Amosenkiene, Aukse 等
1. Introduction
The safety and quality of drinking water standards in Lithuania are
established by the Lithuanian Hygienic Norm HN24:2003 "Drinking
water safety and quality requirements" and are based on European
Drinking Water Directive 98/83/EB. In Lithuania all drinking water is
supplied from groundwater sources, so basically it is of good quality
and does not require complicated water treatment technologies. Some
water quality changes may occur in water supply network. These negative
changes are caused by residual concentration of disinfectant and water
interaction with organic and inorganic compounds. The pipeline's
scale is easily dislodged by flowing water (Tang et al. 2006). Scale may
form because of physical, chemical and biological processes in the
drinking water distribution network (Verberk et al. 2009). The formation
of scale is strongly affected by the pipeline's material (Cerrato
et al. 2006). Different content of relevant elements can be obtained in
different pipelines (plastic, cast iron or steel) (Tang et al. 2006;
Gerke et al. 2008). Water quality also has influence on scale formation
(Gerke et al. 2008). Scale that form on inner pipeline's walls may
affect the organoleptic indicators' changes (Echeverria et al.
2009). For example, if water stays in cast iron or steel pipelines for a
definite time like 125 hours, it can reach high turbidity level
(Nawrocki et al. 2010).
One of the main causes of scale formation is the corrosion of steel
and iron pipelines (Agatemor, Okolo 2008). The most intensive corrosion
of metallic pipes occurs during the first few years, later it decreases
(Sarin et al. 2004). Corrosion activity depends on water temperature,
pH, alkalinity, dissolved oxygen concentration, and water flow
circulation rate (Tang et al. 2006; Gerke et al. 2008; McNeill, Edwards
2002; Nawrocki et al. 2010). The key factor of corrosion activity is
dissolved oxygen concentration. By increasing the dissolved oxygen
concentration, the corrosion rate also increases. If water pH is higher
than 8, then the rate of the corrosion process will increase. The
influence of water temperature on the corrosion rate is ambiguous. If
the corrosion rate's limiting factor is oxygen diffusion, then in
higher temperature oxygen diffusion and convection increase and this
leads to an increase of corrosion rate (Gerke et al. 2008; McNeill,
Edwards 2002; Nawrocki et al. 2010).
In some cases it is possible to find microorganisms in drinking
water networks that stay active even after disinfection (Lehtola et al.
2005; Langmark et al. 2005). Many of these microorganisms may also
become attached to inner pipe walls and form thin 10 till 30 um biofilm
(Bonadonna et al. 2009; Srinivasan et al. 2008). Biofilm is formed by
heterotrophic bacteria, fungi, protozoas, threadworms and crustaceans,
pathogenic bacteria and even viruses e.g. enterovirus or adenovirus may
also develop in biofilm (Berry et al. 2006). The formation of biofilm on
inner water pipeline's walls is strongly related to pipeline
material physical characteristics such as surface roughness (Ramirez et
al. 2009).
The object of this research is developed from the need to analyze
the impact of materials used for pipelines on water quality in order to
suggest a model that corresponds to sustainable development
requirements.
The aim of the research is to complete an analysis of the
sustainable development of water supply pipelines that were
inappropriate because of decreased water quality in urban areas of
Lithuania, as well as structuring of the chemical content of pipelines
for further increase of supplied water quality.
The following tasks were set and completed during the
investigation:
1. Analysis of the chemical impact of pipelines' materials on
water quality;
2. Analysis of water quality changes by defining pipelines material
in order to insure sustainable water supply network development.
The main hypothesis is defined as follows: materials of the
drinking water supply network in urban regions do not correspond to
sustainable development requirements.
Specific hypotheses are:
1. Depending on the pipeline's materials there is an
occurrence of negative water quality changes in water supply networks
and water users taps;
2. Pipelines made from plastic materials are more sustainable
following possible impact on water quality than pipelines from metallic
materials.
2. Evaluation of the existing situation in Lithuania
The main part of Lithuania's water network is based on cast
iron pipelines, which compose of approximately 80% of all urban water
networks. Eight different Lithuanian towns were analyzed (Fig. 1):
Zarasai, Silute, Kupiskis, Kaunas, Druskininkai, Visaginas, Klaipeda and
Nida.
[FIGURE 1 OMITTED]
The dominant pipeline material is cast iron and takes approximately
56.6% of all analyzed drinking water distribution pipelines material;
then twice less of steel--22.5% and plastic--20.7%. The same tendency is
found in all Lithuanian water supply systems (Valentukeviciene et al.
2009).
Depending on the pipeline's material there is an occurrence of
negative water quality changes in water supply networks. The main places
where water changed its quality were: main water supply pipelines,
"dead-end" points and user's taps. This shows that main
water quality changing factors were: water interaction with the
pipelines material and water stagnation time in pipelines. These factors
led to increased total iron, ammonium ions and manganese concentrations.
Table 1 shows existing situation of water supply distribution network in
Lithuanian urban areas.
In almost all cases the water was prepared in water treatment
plants, with removal of exceed total iron and manganese concentrations.
Only in Silute water was distributed for consumers without treatment. In
almost all groundwater treatment cases in Lithuania, total iron and
manganese concentrations are typical components that need to be
decreased (Ljung, Wahter 2007; Santamaria 2008; Tang et al. 2006). High
nitrites concentrations can have negative influence on water user's
health conditions (Gladwin et al. 2004; Rivett et al. 2008). These
examples describe the water quality and the water network situation all
over Lithuania.
Reviewing the above presented facts that show the existing
situation of water distribution network of Lithuanian urban areas the
main hypothesis of the research is confirmed. It says that materials of
the drinking water supply network in urban regions do not correspond to
sustainable development requirements, when water supply, instead of
providing acceptable quality of essential drinking water, changes its
primary indicators to the unacceptable values (Table 2). For example, in
those described towns where the main part of water distribution network
pipelines was made of cast iron, increased total iron concentration was
detected.
Changes were observed in both places: at the users' taps and
at the main water pipelines end points. These numbers illustrate how
water changes its quality by the time when it gets from water treatment
plant to the consumer (Verberk et al. 2009).
3. Water analysis approach and research methodology
In this investigation analytical and descriptive methods were used.
The lab-scaled pipelines that were specially designed for the purpose of
this research were the research instruments. Techniques of research
were: field investigation, action investigation and combined techniques.
The experimental pipeline's system was made from different material
pipes and included: new galvanized steel pipe, 25-year-old steel pipe
and polyethylene (PE) pipe. In certain experimental pipeline the system
was provided with permanent water circulation. Water circulation rate
was 0.3 m/s. Imitation of night regime, when water is standing still,
was also provided in a certain experimental model.
The investigation included 150 samples that were obtained in
different water stagnation times in pipelines, three pipelines of which
had treated water quality and 3 pipelines had raw groundwater quality.
Treated water was prepared from the ground water of Antaviliai (Vilnius,
Lithuania) water treatment plant. Water and scale samples were taken
from the system right after the night regime. The following indicators
were set for the water quality and scale content: total iron, manganese,
ammonium ions, nitrate and nitrite concentrations, turbidity and
chemical oxygen demand ([COD.sub.Cr]). All soft scale materials were
analyzed following the procedures applied for diluted samples.
Comparative approach has been taken into account when lab-scaled
experiment was carried out. The results from the experimental
investigation were statistically estimated from the registered analyses.
The average concentration at the typical point was calculated from three
measured values of one sample.
Collected water samples were then analyzed at International
Standards (ISO) and/or European Norms (EN) approved methods for
determination of water quality indicators and toxic parameters.
The quantitative results are presented as the arithmetic mean of
six independent measurements (x [+ or -] SD, n = 6). Significant
differences (p < 0.05) were removed from the result estimations and
the measurements were analyzed once again. The data from the
experimental investigation were statistically calculated from the
registered analyses. The concentration of substances (Fe, Mn and NH4+)
was measured 11 times in raw water, in sampling taps and in treated
water. The average concentration at typical points was:
[bar.c] = 1/n [k.summation over (i=1)] [c.sub.i][m.sub.i]. (1)
Where: [c.sub.i]--concentration of substances at typical points;
[m.sub.i]--probability at the occurrence of concentration; n--number of
days; k--number of different values of the concentration.
The average concentrations of substances, mentioned above, at the
characteristic point were also calculated. The standard statistical
estimation error of the arithmetic average was approximately 11%.
3.1. Laboratory scaled pilot equipment
Laboratory scaled pilot equipment was located in the laboratory of
Vilnius Gediminas Technical University (Lithuania). The pipeline at the
laboratory is a metallic or plastic till and the taps mainly used for
sampling and control procedures. Treated water dominates the drinking
water supply. The inside pipelines layer consist of PE (plastic pipes),
corrosion layer (25 years old steel pipes), zinc layer (new galvanized
pipes). Those three layers are very common for Lithuanian drinking water
supply. For further details about the water quality see Table 3. Seven
sampling taps (by the end of each pipe) were established 1.5 m apart
within those pipelines, in a diameter of 15 mm. The dominate water flow
velocity was 0.3 m/s and water stagnation was 9 h on night time.
Pipes sections were designed and constructed for three materials
(plastic, 25-year-old steel, new galvanized steel) with an additional
pipe section of plastic to serve as control. These systems helped to
determine the variation of water quality, sediments growth, and
formation of scaling on the pipe surface. Also, these sections allowed
obtaining similar conditions to a water distribution system. Each system
consisted of a 1.5 m long and 0.015 m inside diameter pipeline, which
was connected at both ends with plastic pipeline to form a closed pipe
section. Each section operated at two different conditions; at
flow-through during 7 days in order to provide real operation condition
of a distribution system and at recirculation-flow during each night in
order to provide a longer retention time and to increase water-pipe wall
interaction; the latter flow condition will allow a more clear
evaluation of variations in water parameters. The adequacy of the system
to operate in any configuration was accomplished through a series of
valves. Each system had a pump, flow meter, sampling valve and a set of
valves to adjust the operation of the system.
3.2. Sampling of water and sediments
Samples of water and pipelines sediments were collected from the 7
sampling sections in September-June 2009-2010. Four replicate water
samples were collected from each section and directly from sampling taps
within each of 7 sections. After the removal of junctions and valves,
sediments scratches were taken to a depth of 1.5 m using a cylindrical
steel tube with 12 mm diameter softly adjusted to the pipeline inside
wall. These sediments samples were diluted with distillated water till
20 ml in the laboratory into separate flasks and stored in hermetically
safe conditions at 4[degrees]C until processed.
Water samples of the 7 different sampling taps collected were
filtered of any suspended material, identified to sediments level in the
laboratory and the fresh water sample was analyzed for determination of
manganese, total iron, ammonium ions, nitrates and nitrites
concentrations (see below). The samples were then analyzed at
International Standards (ISO) and/or European Norms (EN) approved
conditions for determination of water quality and sediments suspended
solids. Solutions of sediments samples taken from pipelines inside walls
were also used for chemical analyses.
The sediment samples (20 ml) were also diluted using the method
described by determination instruction manuals for each indicator.
3.3. Chemical analyses
A water quality analyses were made and certain technological
parameters were determined for the control and evaluation of water
quality changes processes using international standard methods:
manganese concentration, mg/L; total iron concentration, mg/L; ammonium
ions concentrations, mg/L; nitrates and nitrites concentrations, mg/L;
and other relevant parameters (e.g. pH, Chemical Oxygen Demands). Raw
water samples were analyzed in the laboratory of drinking water, a
department within the "Vilniaus vandenys", UAB, Vilnius
(Lithuania). The analyses were accompanied by fast quality control
measures by "MERCK-SYSTEM" quick tests. In case of any
significant differences all samples were analyzed once or twice again.
Suspended solids from pipelines sediments samples were analyzed
using International Standard method, including samples preparation
procedures and heating till constant weight.
3.4. Statistical analyses
The quantitative results are presented as the arithmetic means of
six independent measurements. Significant differences were removed from
the estimation of results and the measurements were analyzed once again.
The concentrations of the above mentioned substances were measured 11
times in raw water, treated water, in sampling taps and in the water
storage reservoirs. The average concentrations at typical points were
estimated. The standard statistical estimation error of the arithmetic
average was approximately 11%.
The dependencies between different compounds concentrations and
water quality indicators in different pipes were find out after
statistical analyses using Mathcad 2001 Professional software.
4. Results and discussion
The research carried out at lab-scaled pipelines shows: minimal
total iron concentration was observed in plastic pipes, it was 0.13-0.38
mg/l. Manganese concentration was minimal in galvanized steel pipes
0.12-2.10 mg/l and after 295 hours manganese concentration began to
decline further. Fluctuation of ammonium ions and nitrate concentration
increased in all pipelines (plastic, galvanized steel and old steel
pipes), when concentrations of nitrite were decreased in all pipes.
The determined ammonium ions concentrations ([C.sub.AMMON]) in the
treated water of the 25-year-old steel pipes operated with 12 h
retention time are presented in dependency to nitrite concentrations
([C.sub.NITRITE]) and can be estimated following 2nd equation.
[C.sub.AMMON] = 3855 x [C.sup.3.sub.NITRITE] - 450 x
[C.sub.2.sub.NITRITE] - 1.285 X [C.sub.NITRITE] + 0.96. (2)
Measured nitrogen compounds did not exceed European Drinking Water
Directive requirements (Table 3). The amount of particular components
shown in Table 3 relates to the water enriched with dislodged from pipe
scale.
Total iron concentration and [COD.sub.Cr] were minimal in PE pipes,
when manganese concentration was minimal in galvanized steel pipes. In
case of old steel pipes total iron and manganese concentrations were
exceed EU Directive 98/83/EB requirements. Finally, it was found that
there is no unique pipeline material that insures sustainability of
water distribution network in all cases.
However, in order to satisfy consumer needs it is very important
not only to choose suitable water treatment technology, but also,
depending on water features, to choose suitable materials for water
distribution network.
In conclusion of this research it was considered that the following
model of actions must be applied:
1. Material of water network must be chosen depending on the
quality of the drinking water.
2. If water contains manganese, it is inadvisable to use plastic
pipes and it is better to choose a different metallic material for the
water pipelines. During the research it was found that pipelines from
plastic influenced the manganese concentration increase in the water
network. Water also becomes black colored and is inappropriate to use
for drinking purposes. These changes can be explained in the following
way: plastic material is not polar and electron exchange with manganese
is not possible, thus the manganese sticks to the inner pipe walls and
form sediments. Pressure caused by the water flow between water and the
pipeline wall increase the manganese emission from the sediments.
Meanwhile, cast iron pipe internal surface has lots of electrons, which
can be exchanged with manganese. Manganese concentration may also
increase because of water stagnation in the pipes.
3. If water contains enlarged total iron concentration, it is
better to use plastic pipes. This engineering solution helps to avoid
corrosion process that creates adverse conditions in water network.
Otherwise water can become turbid, brown colored and eventually
unsuitable for drinking purposes.
4. If there is a possibility of microorganism occurrence and
biofilm formation in the water network, it is better to use pipeline
material that does not provide any opportunity for microorganisms to
attach to the pipe wall. In this case it is needed to choose pipeline
material with smaller wall roughness, to avoid suitable conditions for
microorganisms to develop. For this purpose it is recommended to use
plastic material.
5. The necessity to proceed the EIA (Environmental Impact
Assessment) is obvious in all cases of pipelines materials selection in
order to be sure which option is really in accordance to the idea of
sustainability.
Therefore, if environmental engineers wish to carry out all
sustainable development requirements in each case they need to choose
pipeline material that is most suitable for distributing water,
depending on water quality indicators. If water network will be designed
on the basis of sustainable development policy following positive
changes will be achieved: less water reaction with pipelines, less water
quality changes, more consumers satisfied with water quality, longer
pipeline exploitation period, more sustainable usage of natural
resources and water network development in urban areas. General
compliance to sustainable development policy shows how suggested model
of actions helps to provide more sustainable engineering solutions
(Table 4).
Nowadays when the environmental issues become crucial, researchers
of all fields have to work hand by hand and water engineers are no
exceptions (Baltrenas, Kazlauskiene 2009; Ginevicius, Podvezko 2009;
Sakalauskas, Zavadskas 2009), when the main research fields are
operation research and sustainable development (Zavadskas, Turskis
2011). Urban utilities builders should take greater account of the
environmental requirements during teritory planning procedures
(Ustinovichius et al. 2011). It is essential to take into consideration
that the technological intensity of products reduces energy consumption,
which is related to restructuring of energy intensive industries into
more advanced and energy saving ones with higher value added per unit of
product, but with lower energy consumption per unit of product (Bojnec,
Papler 2011). To make it more efficient, the modernization of apartment
houses must be integrated--an entire block or residential area must be
renovated and the principles of sustainable development must be followed
(Raslanas et al. 2011).
Insurance of sustainability of water distribution network design
and construction is leading to complex solutions on simplification
issue.
5. Conclusions
Certain investigation was provided to study water quality changes
depending on different pipelines material. Relevance of the topic arose
from the sustainable condition of drinking water network in Lithuanian
urban areas. During the research there was a review of existing
situation of drinking water network in some typical towns of Lithuania
and percentage repartition of pipeline material was defined. Carrying
out the studies it was determinate causes of water quality changes and
detected typical water network places where water changed its quality.
All the results of experimental analysis are given in sustainable
development point of view. When the results were estimated to insure
sustainability of drinking water network a certain model of actions was
suggested. This model of actions helps to structure the chemical content
of pipeline material for further increase of supplied water quality and
simplification of maintenance.
By taking a general view of the results of this research it can be
affirmed that there is no unique pipeline material that insures
sustainability of water distribution network in all cases. For this
reason environmental engineers must take more responsibility in design
of water distribution network. With the purpose to choose the most
suitable pipeline material it is important to change a present-day
attitude towards technologies to a more sustainable point of view. By
choosing the best equipment for drinking water networks, it is important
to follow a sustainable development policy: to evaluate the life quality
of inhabitants and their water supply network's life cycle.
Additional knowledge of these above mentioned facts would improve the
sustainable development of urban water supplies, and also develop the
correct attitude towards a globally sustainable living environment.
http://dx.doi.org/10.3846/20294913.2011.649957
Acknowledgement
The authors of this article are involved in deliverable activities
on the Sustainable Living Environment project at Environmental
Engineering faculty of Vilnius Gediminas Technical University. We are
grateful to "Vilniaus vandenys", UAB, for the support in
research activities and personally to the Director of Production
Vytautas Kisielis who helped with practical consultancy.
References
Agatemor, C.; Okolo, P. O. 2008. Studies of corrosion tendency of
drinking water in the distribution system at the University of Benin,
Environmentalist 28: 379-384. doi:10.1007/s10669-007-9152-2
Baltrenas, P.; Kazlauskiene, A. 2009. Sustainable ecological
development reducing negative effects of road maintenance salts,
Technological and Economic Development of Economy 15(1): 178-188.
doi:10.3846/1392-8619.2009.15.178-188
Berry, D.; Xi, C.; Raskin, L. 2006. Microbial ecology of drinking
water distribution systems, Current Opinion in Biotechnology 17(3):
297-302. doi:10.1016/j.copbio.2006.05.007
Bojnec, S.; Papler, D. 2011. Economic efficiency, energy
consumption and sustainable development, Journal of Business Economics
and Management 12(2): 353-374. doi:10.3846/16111699.2011.573278
Bonadonna, L.; Briancesco, R.; Libera, S. D.; Lacchetti, I.;
Paradiso, R.; Semproni, M. 2009. Microbial characterization of water and
biofilms in drinking water distribution systems at sport facilities,
Cent Eur J Public Health 17(2): 99-102.
Cerrato, J. M.; Reyes, L. P.; Alvarado, C. N.; Dietrich, A. M.
2006. Effect of PVC and iron materials on Mn(II) deposition in drinking
water distribution systems, Water Research 40(14): 2720-2726.
doi:10.1016/j.watres.2006.04.035
Echeverria, F.; Castano, J. G.; Arroyave, C.; Penuela, G.; Ramirez,
A.; Ochoa, S.; Morato, J. 2009. Characterization of deposits formed in a
water distribution system, Ingeniare. Revista Chilena de Ingenieria
17(2): 275-281.
Gerke, T. L.; Maynard, J. B.; Schock, M. R.; Lytle, D. L. 2008.
Physiochemical characterization of five iron tubercles from a single
drinking water distribution system: possible new insights on their
formation and growth, Corrosion Science 50(7): 2030-2039.
doi:10.1016/j.corsci.2008.05.005
Ginevicius, R.; Podvezko, V. 2009. Evaluating the changes in
economic and social development of Lithuanian counties by multiple
criteria methods, Technological and Economic Development of Economy
15(3): 418-436. doi:10.3846/1392-8619.2009.15.418-436
Gladwin, M. T.; Crawford, J. H.; Patel, R. P. 2004. Biomedical
implications for hemoglobin interaction with nitric oxide, Free Radical
Biology and Medicine 37: 442-453.
Langmark, J.; Storey, M. V.; Ashbolt, N. J.; Stenstro, T. A. 2005.
Biofilms in an urban water distribution system: measurement of biofilm
biomass, pathogens and pathogen persistence within the Greater Stockholm
area, Sweden, Water Science and Technology 52: 181-188.
Lehtola, M. J.; Miettinen, I. T.; Lampola, T.; Hirvonen, A.;
Vartiainen, T.; Martikainen, P. J. 2005. Pipeline materials modify the
effectiveness of disinfectants in drinking water distribution systems,
Water Research 39: 1962-1971. doi:10.1016/j.watres.2005.03.009
Ljung, K.; Wahter, M. 2007. Time to Re-evaluate the guideline value
for manganese in drinking water, Environ Health Perspect 115: 1533-1539.
doi:10.1289/ehp.10316
McNeill, L. S.; Edwards, M. 2002. The importance of temperature in
assessing iron pipe corrosion in water distribution systems,
Environmental Monitoring and Assessment 77: 229-242.
doi:10.1023/A:1016021815596
Nawrocki, J.; Raczyk-Stanislawiak, U.; Swietlik, J.; Olejnik, A.;
Sroka, M. J. 2010. Corrosion in a distribution system: steady water and
its composition, Water Research 44: 1863-1872.
doi:10.1016/j.watres.2009.12.020
Ramirez, E.; Rios, J. F.; Calderon, J. A.; Echeverria, F.; Penuela,
G. 2009. Alteration of the drinking water quality by different metallic
Materials used in distribution systems, Suplemento de la Revista
Latinoamericana de Metalurgia y Materiales S1 (4): 1443-1450.
Raslanas, S.; Alchimovien?, J.; Banaitien?, N. 2011. Residential
areas with apartment houses: analysis of the condition of buildings,
planning issues, retrofit strategies and scenarios, International
Journal of Strategic Property Management 15(2): 152-172.
doi:10.3846/1648715X.2011.586531
Rivett, M. O.; Buss, S. R.; Morgan, P.; Smith, J. W. N.; Bemment,
C. D. 2008. Nitrate attenuation in groundwater: a review of
biogeochemical controlling processes, Water Research 42(16): 4215-4232.
doi:10.1016/j.watres.2008.07.020
Sakalauskas, L.; Zavadskas, E. K. 2009. Optimization and
intelligent decisions, Technological and Economic Development of Economy
15(2): 189-196. doi:10.3846/1392-8619.2009.15.189-196
Santamaria, A. B. 2008. Manganese exposure, essentiality and
toxicity, The Indian Journal of Medical Research 128(4): 484-500.
Sarin, P.; Snoeyink, V. L.; Lytle, D. A.; Kriven, W. M. 2004. Iron
corrosion scales: model for scale growth, iron release, and colored
water formation, Journal of Environmental Engineering 130(4): 364-373.
doi:10.1061/(ASCE)0733-9372(2004)130:4(364)
Srinivasan, S.; Harrington, G. W.; Xagoraraki, I.; Goel, R. 2008.
Factors affecting bulk to total bacteria ratio in drinking water
distribution systems, Water Research 42(13): 3393-3404.
doi:10.1016/j.watres.2008.04.025
Tang, Z.; Hong, S.; Xiao, W.; Taylor, J. 2006. Characteristics of
iron corrosion scales established under blending of ground, surface, and
saline waters and their impacts on iron release in the pipe distribution
system, Corrosion Science 48: 322-342. doi:10.1016/j.corsci.2005.02.005
Ustinovichius, L.; Barvidas, A.; Vishnevskaja, A.; Ashikhmin, I. V.
2011. Multicriteria verbal analysis of territory planning system's
models from legislative perspective, Journal of Civil Engineering and
Management 17(1): 16-26. doi:10.3846/13923730.2011.554173
Valentukeviciene, M.; Amosenkiene, A.; Dauknys, R. 2009. Quality
changes of drinking water in the water supply network (case study from
Lithuania), Annals of Warsaw University of Life Sciences--SGGW, Land
Reclamation 41: 109-118.
Verberk, J. Q. J. C.; Vreeburg, J. H. G.; Rietveld, L. C.; Van
Dijk, J. C. 2009. Particulate fingerprinting of water quality in the
distribution system, Water SA 35(2): 192-199.
Zavadskas, E. K.; Turskis, Z. 2011. Multiple criteria decision
making (MCDM) methods in economics: an overview, Technological and
Economic Development of Economy 17(2): 397-427.
doi:10.3846/20294913.2011.593291
Marina Valentukeviciene (1), Gytautas Ignatavicius (2), Aukse
Amosenkiene (3)
(1,3) Faculty of Environmental Engineering, Vilnius Gediminas
Technical University, Sauletekio al. 11, LT-10223 Vilnius, Lithuania
(2) Faculty of Nature Science, Vilnius University, Ecology and
Environmental Center, M. K. Ciurlionio g. 21, LT-03101 Vilnius,
Lithuania
E-mails: (1) marina.valentukeviciene@vgtu.lt (corresponding
author); (2) gytis@takas.lt; (3) a.aukse@vv.lt
Received 28 October 2010; accepted 29 August 2011
Marina VALENTUKEVICIENE is Associated Professor at Vilnius
Gediminas Technical University and European projects evaluator for EC.
Research interests: eco-friendly water treatment technologies,
sustainable use of water resources, environmental impact assessment, and
water reuse technologies, sustainable living environment.
Gytautas IGNATAVICIUS is Associated Professor at Faculty of Natural
Sciences, Ecology and Environmental Center, Vilnius University. Research
interests: eco-friendly environmental engineering technologies,
sustainable use of natural resources, environmental impact assessment,
sustainable living environment.
Aukse AMOSENKIENE is Doctoral student of Vilnius Gediminas
Technical University and Manager of Water Supply Department at
"Vilniaus vandenys", UAB. Research interests: water supply,
improvement of water quality, sustainable water use, sustainable
pipelines materials.
Table 1. Existing situation of water supply distribution network in
different Lithuanian urban areas
Pipelines materials
Name of percentage of total
the town length (%)
cast steel plastic
iron (PE)
Zarasai 40 5 55
Silute 60 10 30
Kupiskis 90 -- 10
Kaunas 80 15 5
Druskininkai 65 35
Visaginas 30 60 10
Klaipeda 10 90 --
Nida 78 -- 22
Name of Negative water Indicators increased
the town quality changes
points
Zarasai Main water pipelines Total iron
end points
Silute User taps Total iron, Ammonium
Kupiskis User taps Ammonium
Kaunas Main water pipelines Total iron,
end points Ammonium, Manganese
Druskininkai Main water pipelines Total iron
end points, User
taps
Visaginas Main water pipelines Turbidity
end points
Klaipeda User taps Manganese, Nitrite
Nida User taps Total iron,
Manganese
Table 2. The analysis of sustainable development of water supply in
urban areas of Lithuania
Total iron, Total iron,
Water quality Ammonium, Ammonium, Total iron
indicators Manganese, Manganese,
Turbidity Nitrite
Places of water Main water User taps Main water
quality changes pipelines end pipelines end
points points and user
taps
Water quality 43 43 14
changes
percentage of
total water
supply, %
Table 3. Results of experimental research
Indicating values depending
Initial on pipeline material
Water quality water
indicators quality Plastic Galvanized Old steel
indicators pipes (PE) steel pipes pipes
Total iron 0.09-0.10 0.13-0.38 0.10-0.50 2.39-4.81
concentration,
mg/L
Manganese 0.02-0.05 0.18-0.85 0.06-0.79 0.12-2.10
concentration, mg/l
mg/L
[COD.sub.Cr], 10-12 41-120 73-175 40-176
mg[O.sub.2]/L
Fluctuation 0.02-0.05 increase up no abnormal decrease
of manganese to 1.35 changes after 295 h
concentration
in pipes
Table 4. Compliance to sustainable development policy
Less More
Water reaction with pipelines Good quality water for drinking
purposes
Sediment and biofilm formation Pipeline water throughput
Water quality changes Consumers satisfied with water
quality
Spending money on water network Longer pipeline exploitation
rehabilitation period
Sustainable use of ground water resources
Sustainable use of natural resources for pipeline material
Sustainable water network development
