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Seventeenth International Water Technology Conference, IWTC 17 2013, Istanbul, Turkey
1
SURFACE AND GROUNDWATER CONTAMINATION IN SHKODER-TRUSH
AQUIFER (ALBANIA)
Halil Murat ÖZLER
1, Anila Xhahysa
2
1 İstanbul Gelişim University, Faculty of Engineering and Architecture, Department of Civil
[email protected]: mail-E Istanbul ,Turkey-Engineering, Avcılar, İstanbul
[email protected]: -E Department of Civil Engineering, EPOKA University, Albania2
ABSTRACT
The objective of this paper is to assess and evaluate the conditions of the surface and
groundwater resources in the Shkoder-Trush Regions. A large amount of private and public
well data whose water chemical analysis were performed within the years 2011-2012, thus
they provide a relatively recent information about the underground water quality in Shkodra
City. The risk of pollution is very high because the aquifer’s cover layer is very thin; the
running rivers (Drini and Buna Rivers) are very polluted due to over urbanization and wastes.
In addition, the groundwater in Shkoder-Trush Regions has high values of NO2, NO3, NH4
and OM, indicating a possible pollution in the coastal aquifer of Shkoder-Trush. The current
situation in the region is evaluated through data from wells and streams and Water budget to
evaluate the groundwater characteristics. The distributions of different chemical properties are
mapped to identify the most problematic zones by using GIS techniques. The study focuses
on problems such as the contamination due to stream water and groundwater interaction in
Trush region. The effects of these phenomena are studied and some possible remedies are
discussed in this paper.
Keywords: Groundwater, Contamination, Aquifer, Shkoder, Drina and Buna river
1 INTRODUCTION
Drinking water is one of the main concerns one populated area should focus on, continuously and
rigorously. It’s safety is directly related to our health, and its effects may severely affect our lives.
Several contaminants may be found in the main supply water systems of cities, and especially in
villages. The most known are the high levels of nitrate, nitrite and ammonia, whose sources may be
pesticides or urban wastes. Thus it is an urgent need that all the main supply water systems are
controlled for the possible presence of the above mentioned contaminants.
Shkoder-Trush regions are located in North Albania and it is bounded by the Adriatic Sea in West
and Lake Shkodra in the East. During the past 20 years the population of the region has increased
rapidly and now it is one of the most densely populated regions in Albania. Shkoder-Trush regions are
the areas most prone to possible contaminations, due to lack of regular analysis and presence of near
farms, and landfills. Thus in this paper will be studied a specific regions in Shkoder-Trush. The water
analyses performed there show a relatively high level of contamination by nitrite, nitrate and
ammonium.
2 STUDY AREA Shkoder-Trush regions are situated on North Albania near the Lake Shkoder. 10 m above the sea
level and surrounded by a mountainous relief. Shkoder Lake is the biggest and the most interesting
lake of Balkan hydrographical network. Its catchments area is 5179 km2, and the average altitude is
770 m Abs . Many different affluent, such as Moraca, Zeta, Ceni, Ziveri, etc discharge into Shkoder
Lake. The only emissary of this lake is Buna River, 43 km long. In its flow, about 1.5 km away from
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the lake, this river gathers the plenty water of Drini river and they together discharge into Adriatic Sea.
Drini River discharge into Buna riverbed not only obstructs the free discharge of this lake water into
the Adriatic Sea, but also it causes opposite direction discharge. In these conditions Buna River, being
a typical emissary of Shkoder Lake, turns into its affluent. In this conditions, the hydrographic system:
“Shkoder Lake – Buna River –Drini River is distinguished for its specific very complicated hydraulic
nature that determines in reality the nature of the limnological regime of this lake.
Figure 1 Location map of Shkoder-Trush regions
3 PURPOSE AND SCOPE
The aim of this report is: 1) to describe the groundwater quality of Shkoder-Trush regions based on
the chemical properties and to identify potential sources of groundwater pollution, discussing the
possible remedies; 2) to describe the groundwater quality in Shkoder-Trush regions and highlights the
areas, describe the possible sources and discuss some future solutions.
4 METHODS
Field Measurements - Groundwater monitoring is performed by the Geological Institute of Albania
through drilling logs and pumping stations wells.
For this study there are used two time series of the water sample: a) water monitoring samples for
2012 for the Shkoder-Trush Regions. At each sample station is determined the static and dynamic
level of groundwater table, cover depth and the height of the aquifer layer. Ph, temperature and
conductivity were measure in situ.
Chemical Analyses -
Map Generation - The results of the chemical analyses are used to generate the map distribution of
the different chemical substances in the study area. The mapping of the chemical properties was
performed with Surfer 10 software. The coordinates of the water samples are converted from ALB87
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coordinate system to UTM coordinate system. The chemical concentrations are expressed as mg/l.
Based on these mappings the hot spots will be identified.
A large amount of well data (60 private and public wells) whose water chemical analysis were
performed with photo-spectrometer in Shkoder. For each sample a chemical analyses was conducted
to find out the concentration of different chemical substances like: Ca+, Na+, K+, Mg+, HCO3-, Cl-,
SiO2, O2, Fe+, CO3, NH4, NO3, NO2, Total Dissolved Solids (TDS) and hardness. Their analysis date
range within the years 2011-2012, thus they provide a relatively recent information about the
groundwater quality in Shkodra City. Their exact location with the respective chemical properties will
be summarized below.
A specific attention was given to the Trush village, and the area surrounding it in order to better
understand the high level of contaminations of its main supply system. Despite the target of this study,
is this region, an overall view of the underground water quality of the entire city, helps us to have a
better picture of where are the spot areas, and deduce the common causes of pollution. In total there
are 280 well data, but the more exact ones were selected and their mapping is done as follows, in order
to provide an accurate view of the quality of water in these wells. The chemical properties of the well
water contain the following parameters: pH, NO2, NO3, NH4+, OM and hardness. The well data
contain also the water level as the depth of the well is known. The corresponding maps for each of the
parameters are presented.
5 HYDROGEOLOGY
The lake Shkoder basin, located in one of the tectonic low-lying areas bounded by the Dinaric Alps,
the Bjeshket hills and the Namuna mountain, mainly consists of calcareous sedimentary rocks that
give rise to part of the classical Karst topography. The geology of the catchment basin is also
characterised by clastic and flysch deposits from the early and middle Triassic eras, eruptive rocks of
the middle Triassic and in the north-eastern part, flysch deposits from the Late Cretaceous era.
Furthermore, along the central part of the drainage area, in the zone that leads from Gatacko Polje to
the southeast of the Kuck Zone, there are sedimentary rocks from the Late Cretaceous and Palaeocene
eras.
Seventeenth International Water Technology Conference, IWTC 17 2013, Istanbul, Turkey
4
Figure 2 Hydrogeology map of Shkoder lake basin. Figure 3 Groundwater level in Shkoder aquifer
In short, the morphological characteristics of Lake Shkoder basin have been determined by complex
geological structures that were formed during the orogenesis processes of the Palaeozoic and Tertiary
Eras. The subsequent glacial and fluvial erosion, coupled with the karstification process of the
limestone rocks surrounding Lake Shkoder and its catchment basin, gave rise to the formation of a
holokarst region (Figure 3). The well data contain also the water level as the depth of the well is
known. The corresponding maps for each of the parameters are presented. Groundwater level range
from sea level to 130 m at the NE (Figure 4).
6 POLLUTION
The guideline properties for drinkable water are based to EPA (USA Environmental Protection
Agency), WHO (World Health Organization), European and Albanian Standards (Table 1). The
hydrochemical property for the 2012 samplings are plotted together with the permitted values
indicated from EPA and WHO.
Table 1 The guideline properties for drinkable water are based to EPA and WHO
6.1 Solid Waste and Sewage Pipes
None of the local units, with the exception of the municipality of Shkoder has a specially designated
waste collection place, while there is no talking of waste processing and waste treatment. Waste is
sporadically disposed in the river and stream beds. Solid waste is a problem in all the waters, as it is
shifted with the currents. Solid waste is transferred through the tributaries to Lake Skadar and through
the Bojana River to the sea. Banks and the large coastal dune and beach areas are covered with solid
waste. Besides the organization of proper waste disposal sites, all one-way systems have to be
abolished in both countries as a matter of urgency. This is especially true for the smaller villages,
where waste is deposited in streams or nearby depressions.
The condition of sewage pipes is worse than water supply pipes. Without exception, all the
communes under consideration have no system of sewage pipes except for the communes of Ana e
Malit and Dajc, which may boast of 5-10 per cent of their area being covered by sewage pipes. Even
in these cases, sewage are collected in open space and are discharged in the closest water streams (the
River Drin and the River Buna respectively) or in common big holes that produce harmful
consequences and pollute the environment.
Sewage pipes do not exist in the majority of the rural areas. Even where there are such pipes,
sewage is discharged in its raw condition in the water streams that cross the settlements. In the hot
season, the hazards increase as the environment is badly polluted and health risks abound. It is of
priority need to include the building of sewage systems in the plans for territorial regulation that need
to be developed in the near future.
The sewage pipes system in the municipality of Shkoder consists of 18 km of secondary pipes, 10.5
km of main collector pipes and 6000 collection holes. Disposal is carried out by pumping stations with
a maximum capacity of 650 l/sec. From the secondary pipes, sewage passes into the main collectors to
Measure units Standard
Max. allowed value
pH 6.5 – 8.5 9.5
Hardness 0 German 10 – 15 20
Organic substances (KMnO4) mg/l O2 1 3
Chlorines mg/l Cl- 25 200
Ammonium mg/l NH4 + 0 0.05
Nitrites mg/l NO2 0 1
Nitrates mg/l NO3 10 10
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be collected in the main pool situated in the entrance to the town. From the pool, sewage is pumped
into the River Drin. Electricity shortages create problems and cause to discharge sewage into the Lake
of Shkodra as it is collected without any prior processing. There are two spots for sewage discharge in
the Lake of Shkodra.
About 35 per cent of the zones use septic holes. The rest of 65 per cent have sewage pipes systems
in highly amortized condition. The two tourist quarters of the town of Shkodra, Shiroka and Zogaj, do
not have sewage pipes systems. Where there are systems they conform to the blueprints of the years
1970-1980. However, illegal and abusive constructions continue to remain a problem and so does the
uncontrolled expansion of informal areas. A positive development is represented by efforts to solve
the problem of collection and disposal of used waters. To date, collection and disposal of used waters
has been a serious problem as it often causes block-ages of sewage holes entailing the burst of sewage
on the ground, to say nothing of the ensuing pollution of underground waters (Maçi, L. and others
2006).
6.2 Surface Flow Contamination
6.2.1. Skodra Lake
Shkodra Lake is the largest lake in the Balkan, shared with Montenegro (Fig. 4). The lake was
formed through tectonic shifts combined probably with karstic processes. River Buna is the
only outflow at the western lakeside; it joins Drini River just 1.5 km from the outlet. Lake
Shkodra is characterized by a rich flora and vegetation.
Figure 4 Main source of pollution of Buna and Drini rivers in Shkoder-Trush region(UNEP, 2000)
Table 2 Water chemistry of Drini river and Lake Shkoder (Abazi U., and Balliu A., 2012)
Years pH EC
mS/m
Ca
Mg/L
Mg
Mg/L
Na
Mg/L
K
Mg/L
CO3
Mg/L
HCO3
Mg/L
Cl
Mg/L
SO4
Mg/L
NO3
Mg/L
NH4
Mg/L
PO4
Mg/L
Drini river-2007 6,8 280 37,67 11,42 3 0,22 6 97,63 14,18 136,9 1,12 0,56 0,20 2008 7,5 270 43,08 10,57 2,76 1,03 9 117,2 21,27 38,91 4,76 2,24 0,30
2009 7,2 290 63,12 14,95 3 1,17 9,6 112,3 15,95 14,41 3,92 1,68 0,40
2010 7,1 300 61,52 12,4 2,3 1,18 9,6 67,73 12,76 9,6 1,84 1,70 0,71
Lake Shkoder min 7,83 234 36,07 4,86 1,54 0,37 0,01 149 6,5 8,50 0,12 0,014 0,006 max 8,85 323 44,60 8,80 2,70 0,45 1,12 164 9,9 15,6 0,45 0,040 0,014
mean 8,19 275 40,18 7,12 2,05 0,41 0,50 156 7,8 12,5 0,25 0,023 0,008
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6.2.2. The river Drini
The Drini is the longest river in Albania with a length of 283 km (Kabo et al., 1990). It has two
main sources, the Black Drini (149 km) and the White Drini (139 km). The Black Drini (in Albanian:
Drini i Zi) originates at Lake Ohrid (Liqeni i Ohrit) and flows through Macedonia and the eastern
territories of Albania. The White Drini (Drini i Bardhë) emerges from the Žljeb Mountain in Kosovo
(Kabo et al., 1990), and merges with the Black Drini near Kukës in northeastern Albania (fig. 4). At
Vau i Dejës it enters the lowlands of Shkodra and splits into two distributaries. One continues to the
south, passing through the plains of Zadrima. Before it reaches Lezha, it is joined by small rivers and
creeks (e.g., Bushat and Gjadër) which emerge from the Shite-Veles Mountains. In Lezha this branch
of the Drini enters the delta plain and finally, between the Ceka and Merxhani lagoons, it reaches the
Gulf of Drini in the Adriatic Sea. In total, this distributary of the Drini, also called ‘Drini of Lezha’
(Drini i Lezhë), is 22.5 km long.
Figure 5 The Drini splits into two branches at Vau Dejes. It flows from the left hand side towards
and as the Drinassa twards Shkodra (Photo:Uncu,2007)
The results show a low electrical conductivity, with lowest values among the samples in this study,
and with a very small variability (Table 2). The anion and cation values resulted also within the
parameters set by SSC. The content of carbonate was between 6.0-9.6 mg/L, increasing from the first
to the fourth sampling year, but still within the acceptable levels of SSC. The opposite happened with
the content of bicarbonate, but again the concentrations were within the norms set by SSC. Phosphate
had relatively high values (max = 0.71 mg L-1) and that might be an additional source of P to the
irrigated soils. Content of sulphate ions was 7 to 20 times lower than the permitted limits and chloride
concentrations were up to 1/100 of the acceptable levels. Neither nitrate concentration, ranging from
1.12 to 3.92 mg L-1
, or ammonia were within the safe intervals for irrigation. Based on these results,
Drini river water is classified as Class II for irrigation. (Abazi, U., and Balliu, A., 2012).
The paper studied the real situation regarding water pollution in the Drini River and Septic system
of Shkoder and Trush cities, mainly Albanian hydrograph network and measures to be taken on the
environmental impact that urban pollution discharges bring. Some physic-chemical parameters of
water samples, such as pH value, electrical conductivity, alkalinity, hardness as well as concentrations
of HCO3 and CO32 were measured, and concentrations of nine elements in water samples were
determined by ICP-MS technique (Table 2).
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6.2.3. Bojana – Buna River
During most of the year the water quality of the Bojana-Buna River is acceptable. But, during
periods of high water levels in its tributaries, pollution increases and water quality worsens. This
happens most frequently in summer during the tourist season. The natural riverbed and water flow of
the Bojana-Buna River are essential for mitigating the impact of wastewaters from the city of Shkodra,
because the river corridor has a high potential for self-purification.
Water quality from the Bojana-Buna is similar to that of Lake Skadar(Table 2), and is below A1
class, which is water of very satisfactory quality. Some examples of other suspended matter, not
categorized, are registered. The numbers of fecal bacteria led to classification as A2 class, and the
numbers of coli bacteria, as A3 class. Solvency class is II. (by Libman).
6.3. Groundwater Contamination in Shkoder-Trush Regions
The most problematic chemical parameters are plotted individually for the Shkoder-Trush Regions
in Figures 6-9. In this section will be presented a large amount of well data (private and public wells)
whose water chemical analysis were performed with photo-spectrometer. Their analysis date range
within the years 2011-2012, thus they provide a relatively recent information about the groundwater
quality in Shkodra City. Their exact location with the respective chemical properties will be
summarized below.
A specific attention was given to the Trush village, and the area surrounding it in order to better
understand the high level of contaminations of its main supply system. Despite the target of this study,
is this region, an overall view of the groundwater quality of the entire city, helps us to have a better
picture of where are the spot areas, and deduce the common causes of pollution. In total there are 280
well data, but the more exact ones were selected and their mapping is done as follows, in order to
provide an accurate view of the quality of water in these wells. The chemical properties of the well
water contain the following parameters: pH, NO2, NO3, NH4+ and Natural Organic Matter (NOM).
6.4. Nitrate
Nitrate is a naturally occurring oxide of nitrogen and is an essential component of all living things.
It is the primary source of nitrogen for plants, and it occurs naturally in soil and water. But if the levels
of nitrate get too high, it can pose a potential health risk. Sources of excess nitrate in water include:
fertilizers, septic systems, wastewater treatment effluent, animal wastes, industrial wastes, and food
processing wastes.
Nitrate levels can be high in streams and rivers due to runoff of nitrogen fertilizer from agricultural
fields and urban lawns. Groundwater is susceptible to contamination from many different chemicals,
including nitrate fertilizers, especially where the water table is shallow and there are no confining units
to reduce migration downward. Most of these contaminated groundwater flow into streams and rivers,
causing elevated nitrate levels in those water bodies downstream. Nitrate concentration is less than
maximum allowable level. Levels of nitrate in water above 50 mg/L indicate that shallow groundwater
drawn by well may be vulnerable to other types of contaminants moving through the soil, including
pesticides. Allowable nitrate Level in Albania. Albanian regulations for nitrate allowable levels in
drinking water are the same as the ones used worldwide. The allowable nitrate level in drinking water
is maximum 50 mg/l(Fig.6).
6.5. Ammonia
Ammonia (NH3) is a colorless, alkaline gas at ambient temperature and pressure, with a distinct
pungent odor. Produced naturally by the biological degradation of nitrogenous matter (e.g., amino
acids) that is present in organic wastes or soil ammonia provides an essential link in the "nitrogen
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cycle" of nature. Ammonia is present in most waters as a result of the biological degradation of
nitrogenous organic matter, although it may also reach groundwater and surface waters from industrial
waste discharges.
Ammonia occurs naturally in drinking water and may stratify in impounded water. Ammonia
should be considered as a potential source of nitrates. Estimated taste and odour thresholds for
ammonia are 35 mg/L (as NH3) and 35 mg/m3 respectively. Sensitive individuals may detect
concentrations an order of magnitude lower.
Figure 6 Nitrate concentration in Shkoder aquifer
Figure 7 Ammonium concentration in Shkoder aquifer
Figure 8 Nitrite concentration in Shkoder aquifer
Figure 9 Natural organic matter in Shkoder aquifer
Seventeenth International Water Technology Conference, IWTC17 Istanbul, 5-7 November 2013
6.6. Nitrite
Nitrite (NO2) is a naturally occurring chemical made of nitrogen (N) and oxygen (O). Nitrogen and
nitrogen compounds, such as nitrite, are found in air, soil, water, and plants. In certain conditions,
when oxygen is unavailable, nitrate (NO2) may be converted to nitrite. Therefore many sources of
nitrate are also potential sources of nitrite.
Sources of nitrite in groundwater include; leaching of chemical fertilizers, leaching of animal
manure, improperly treated septic and sewage discharges, decaying plant or animal material, Erosion
of natural deposits. Maximum Acceptable Concentration in Drinking Water is 1 mg/L. In water, nitrite
has no taste, smell, or colour.
As shown in figure 8, the concentration of the nitrite is largest in the Trusjh zone and in surrounding
areas. This was the main cause that leads us to perform a detailed check of all the other chemical
contaminants of the same nature for this zone. The nitrite level reaches the value of 1.6 mg/L, which is
a relatively high value for drinking water, that is what makes this water be out of standard. The main
water supply system is very near to a channel, where the wastes are thrown, and also there are many
farms surrounding it, which use pesticides and other fertilizers, that makes us believe, that is the main
cause of this high level of nitrate contamination.
6.7. Natural organic matter(NOM)
Natural organic matter (NOM) is broken down organic matter that comes
from plants and animals in the environment. NOM is a collective term, assigned to the realm of all of
this broken down organic matter. Basic structures are created from cellulose, tannin, cutin, and lignin,
along with other various proteins, lipids, and sugars. NOM is very important in the movement of
nutrients in the environment and plays a role in water retention on the surface of the planet. Organic
matter infiltrating into the subsurface from rivers, lakes, and marine systems (Aiken, G., 2002). A
majority of NOM not already in the soil comes from groundwater, which is water under the surface of
the earth. When the groundwater saturates the soil or sediment around it, NOM can freely move
between the phases. Maximum allowable level of natural organic matter in groundwater is 3 mg/l as in
Table 1. In the study area, the levels of Natural organic matter changes between 1-3 mg/L (Fig.9).
7. CONCLUSION
Lake gathers the water of a typical mountainous territory, in spite of the fact that it is situated, on
the Albanian coastal lowland. Shkoder Lake basin is one of the most complicated natural area, in
Europe, as a result of its specific physic-geographical condition: mountainous region, particular land
cover with small vegetation and important flysch formation presence, typical Mediterranean climatic
regime with intensive precipitation, a hydrogeological with powerful ground water flow, etc.
1. Shkoder Lake, Buna River and the Drini River represent a complicated hydrographical system.
Buna is one of the biggest and most important rivers of the Mediterranean Sea. After getting out of the
Shkoder Lake, this river joins the Drini River, forming this particular hydrographical system.
2. The discharge of the Buna River away from the Shkoder Lake depends upon the lake water level
and the Drini River discharge into Buna River.
Nitrate concentration is less than maximum allowable level. Levels of nitrate in water above 50
mg/L indicate that shallow groundwater drawn by well may be vulnerable to other types of
contaminants moving through the soil, including pesticides. Allowable nitrate Level in Albania.
Albanian regulations for nitrate allowable levels in drinking water are the same as the ones used
worldwide. The allowable nitrate level in drinking water is maximum 50 mg/l.
Seventeenth International Water Technology Conference, IWTC17 Istanbul, 5-7 November 2013
As shown in figure 8, the concentration of the nitrite is largest in the Trusjh zone and in surrounding
areas. The nitrite level reaches the value of 1.6 mg/L, which is a relatively high value for drinking
water. The main water supply system is very near to a channel, where the wastes are thrown, and also
there are many farms surrounding it, which use pesticides and other fertilizers, that makes us believe,
that is the main cause of this high level of nitrate contamination.
It occurs naturally in drinking water and may stratify in impounded water. Ammonia should be
considered as a potential source of nitrates. Estimated taste and odour thresholds for ammonia are 35
mg/L (as NH3) and 35 mg/m3 respectively. Sensitive individuals may detect concentrations an order of
magnitude lower.
Maximum allowable level of natural organic matter in groundwater is 3 mg/l as in Table 1. In the
study area, level of Natural organic matter changes between 1-3 mg/L.
8. REFERENCES
[1] Abazi U., and Balliu A., 2012 “Evaluation of irrigation water quality across major water
resources in Albania during a five-year monitoring process”, Journal of Food,
Agriculture & Environment, Vol.10 (2).
[2] Maçi, L. and other.(2006),Regional Environmental Action Plan, Drini River Delta
Shkodra – Lezhe, Tirana.
[3] Rapid Assessment of the Ecological Value of the Bojana – Buna Delta
(Albania/Montenegro)
[4] Pano, N., Stratoberda, P., Frashëri, A., Mustaqi, V. 2008 “Principal elements
limnological regime of Scutary Lake”, BALWOIS 2010 – Ohrid, Republic of
Macedonia – 25- 29 May 2008
[5] MIHO Aleko, KUPE Lirika, JAUPAJ Orjeta, KARJALAINEN Satu Maaria,
HELLSTEN Seppo, PRITZL Gunnar, 2008 “OVERVIEW OF WATER QUALITY OF
ALBANIAN RIVERS” BALWOIS 2008 – Ohrid, Republic of Macedonia – 27, 31 May
2008
[6] George Aiken. 2002, United States of America, United States Geological Survey,
Organic Matter in Ground Water,