The main objective of the present study is to spatially evaluate the water contamination of Khabur River, before it arrives in Zakho City, inside the city, and after it leaves the city of Zakho by heavy metals. Also, the seasonal effects of Zakho municipal wastewater discharged in the Khabur River were detected in this study. The results showed that some heavy metals, such as Ni, were not detected in all studied samples in this study due to their low concentration levels. It is indicated that heavy metals are statistically affected by spatial location and high amounts were detected after leaving, compared to before entering the city which indicates that municipal wastewater is the main source of metal pollution. However, all water tests met the WHO's authorized limits. The average detected concentrations of copper, iron, manganese, and lead ranges from 0.003 to 0.025 mg/L, 0.000 to 0.054 mg/L, and 0.057 to 0.112 mg/L, and 0.014 to 0.135 mg/L respectively, while the highest concentrations of copper and iron were recorded significantly in Bedare (0.025 mg/L, 0.054 mg/L) respectively. The highest concentration of Lead (Pb) was detected in Chamtre and Tawke 0.117 mg/L and 0.135 mg/L respectively and this increase may be due to the presence of oil in the discharged industrial wastewater, in this village. Regarding season’s effects, higher mean concentrations for Mn 0.13423 mg/L, Fe, and 0.04208 mg/L were recorded in the autumn season. However, copper and lead had higher mean concertation 0.02389 mg/L, and 0.097 mg/L respectively, during the winter season, while the lowest mean concentration of copper was recorded in autumn, and lead in the summer season had a minimum concentration. There was a significant difference (P <0.01) in the seasonal variation of Cu, Fe, Mn, and Pb

Wastewater contains poisonous metals which can be moved and accumulated in plants before entering the human body through the food chain. The aim of this research was to investigate the concentrations of toxic metals such as Nickel (Ni), lead (Pb), and copper (Cu) in wastewater, celery plant and farmlands soils of Duhok city Kurdistan of, Iraq. The heavy metals accumulation in the Celery plants, soil and water samples were analyzed by using an atomic absorption spectrophotometer. The results obtained showed that the mean concentrations of Pb, Ni, and Cu in the wastewater and Celery plants samples ranged from 0.45±0.08 to 5.95±0.2, 0.18±0.01 to 1.95±0.28, 0.02± 0.01 to1.13±0.23 mg/L respectively. The pattern of metal buildup in wastewater-irrigated soil is in the order: Cu > Pb > Ni, and the mean concentration of Pb, Ni and Cu in soil ranged between 21.68±0.42 to 118.57±0.07, 1.27±0.47 to 5.70±0.23, 1.28±0.24 to ± 15.12 0.53 mg/kg-1, respectively. While the mean concentration of Pb, Ni and Cu in celery leaves ranged from 1.04±0.22 to 5.22±0.60, 0.52± 0.22 to 4.31± 0.12, respectively. 1.34 ±0.22 to 19.47±0.82, 1.23±0.04 to 7.29± 2.53, 1.01±0.05 to 5.76±1.32 mg/ kg-1, respectively. According to this study, roots contain more heavy metals than leaves. According to the findings, a few of the sampling sites had Pb, Ni, and Cu values that were exceeded the permissible concentration. Celery plants cannot be planted in the Duhok Valley to prevent excessive heavy metal exposure to human health through vegetables, where the main irrigated water source is sewage from the local municipalities. Celery plant irrigation with wastewater has much greater levels of heavy metals than the controls.

Samples of water were collected from the Khabur River in Zakho city in Iraqi Kurdistan Region in three seasons, the summer, autumn, and winter of 2021, at three different locations, before arriving at the city, inside the city, and after passing the city, and some Physio-chemical properties of water were determined to evaluate the spatial and seasonal variation effects on the renowned Khabur River properties. The result revealed the dissolved oxygen DO, biological oxygen demand is significantly (p<0.01) influenced by the summer season than autumn and winter, as the high temperature minimizes the dissolvability of oxygen necessary for life in the water, however, the level of BOD in Khabur river in three seasons not exceeded the recommended level of WHO and Iraqi slandered 3 mg/l. The pH of the Khabur River is not significantly affected by seasonal changes, while EC is significantly affected by seasonal variation. The alkalinity of the Khabur River is significantly higher in summer than in autumn and winter, and the opposite of almost all the studied parameters that increased in winter. The river has a total hardness greater than 200 mg/l as well as total calcium and magnesium. Hardness is significantly high in winter, as the dissolution of both Ca and Mg from bedrock and soil is increased by the action of heavy rainfall on the eroded soil. Regarding the spatial variation, the most studied parameters of the Khabur deteriorated when the river enters Zakho city, as approximately all the sewage water of this city is discharged into the river without any proper treatment.

The river Khabur, the life line of more than 500 thousand of people, supplies water for the important requirements of life. In this work, a total of 192 samples of water were collected at Khabur River, Zakho District. The samples were collected monthly at four different seasons like spring, summer, autumn and winter from March, 2019 to February 2020. The samples of water were examined for total hardness (TH) , total alkalinity (TA), pH, Calcium( Ca2+) , Electrical conductivity (EC), Nitrate (NO3-), total dissolved solids (TDS), Sulfate (SO4 2−) , phosphate, magnesium (Mg2+) BOD, and DO according to the standard methods . The results of the chemical and physical characteristics indicate the water river samples with the following parameters. The total mean values of temperature ranged from (14.461± 14.1469) oC , pH varied from (7.831 ± 0.2842). Conductivity ranged from (560. 25 ±110. 805) µS/cm).Total alkalinity varied from (194.19 ± 69.591) mg/L. Total dissolved solids varied from (355.99 ±71.581) mg/L. Dissolved oxygen varied from (8.219 ± 0.7989) mg/L. Biochemical oxygen Demand (BOD) ranged from (9.857± 6.0760) mg/L. Total hardness varied from ( 535.02 ±78.014) mg/l. Calcium (Ca2+) varied from (409.19 ± 46.875) mg/l. Magnesium (Mg2+) ranged from ( 127.58 ± 46.875) mg/L. Chloride (CL-) varied from ( 26.938 ± 21.2133) mg/L. Nitrate (NO3-) ranged from ( 4.449 ± 2.0327) mg/L. Sulfate (SO4 2−) varied from( 43.24 ±22.479) mg/l. And phosphate ranged from (4.839 ± 1.9139) µg/L. Gradual increase in total alkalinity and hardness towards the downstream is, due to effluents in the Khabur River. Untreated from sewage discharge on river water it causes of high organic matter, phosphate and Nitrate, at high contents in Khabur River .TDS and EC were found moderate in all locations at Khabur River. The total hardness exceeded the permissible limit in all sites. The (Ca2+) and (Mg2+) were exceeded the permissible limit in all sites. In the present study an attempt had been made to determine the levels of wastewater that ultimately discharged into Khabor River without proper treatment.

The worlds major sourcesof drinking water are groundwater particularly wells water. In the present study, the quality of the wells in the 10 villages nearby the city of Zakho were selected for investigation and their suitability for drinking purposes. All the well water samples were analyzed for 11 chemical and physical analysis including dissolved oxygen, total hardness, chloride, total dissolved solids, electrical conductivity, pH, sulfate, and four heavy metals, such as Cu, Fe, Pb, and Zn using standard methods. The results showed that the value of heavy metals in well water samples were in these ranges: Zn (0.027± 0.004 to 0.005 ± 0.007) mg/L; Fe (0.0109 ± 0.035 to 0.183 ± 0.061) mg/L ; Cu (0.001 ± 0.022 to 0.025 ± 0.023) mg/L; Pb (0.045 ± 0.015 to 0.069 ± 0.096) mg/L. The range of physical and chemical parameters were; pH (7.1 to 8.3), EC (411 to1579 µS/cm), TDS (263 to 1010 mg/L), Total Alkalinity (287 to 584 mg/L), Total hardness (176 to 848 mg/L), Chloride (11.6 to 56.9 mg/L), calcium (80 to 673 mg/L), dissolved oxygen (6.1 to 8.7 mg/L), sulfate (10.3 to 42.5 mg/L) and temperature (17.0 to 23.4°C). The results were compared with international standards and showed that the mean values of total hardness and TDS in locations betas, Bezehe and Dolla are ranged from (827.13 ± 5.330), (544.25 ±3.178) ,(782.63 ± 3.257), (930.38 ± 3.545), (675.75± 3.639) ,( 996.25 ± 3.245) mg/L respectivily, were found to be higher than WHO water standards, and unsuitable for drinking use. The results have proven the presence of heavy metal as especially lead, Zn, Cu, and Fe have been containing in the study area. Other parameters were within (WHO) drinking water standards. In conclusion, the other sites of well water sources of the Selevania region are suitable for drinking purposes..

The worlds major sourcesof drinking water are groundwater particularly wells water. In the present study, the quality of the wells in the 10 villages nearby the city of Zakho were selected for investigation and their suitability for drinking purposes. All the well water samples were analyzed for 11 chemical and physical analysis including dissolved oxygen, total hardness, chloride, total dissolved solids, electrical conductivity, pH, sulfate, and four heavy metals, such as Cu, Fe, Pb, and Zn using standard methods. The results showed that the value of heavy metals in well water samples were in these ranges: Zn (0.027± 0.004 to 0.005 ± 0.007) mg/L; Fe (0.0109 ± 0.035 to 0.183 ± 0.061) mg/L ; Cu (0.001 ± 0.022 to 0.025 ± 0.023) mg/L; Pb (0.045 ± 0.015 to 0.069 ± 0.096) mg/L. The range of physical and chemical parameters were; pH (7.1 to 8.3), EC (411 to1579 µS/cm), TDS (263 to 1010 mg/L), Total Alkalinity (287 to 584 mg/L), Total hardness (176 to 848 mg/L), Chloride (11.6 to 56.9 mg/L), calcium (80 to 673 mg/L), dissolved oxygen (6.1 to 8.7 mg/L), sulfate (10.3 to 42.5 mg/L) and temperature (17.0 to 23.4°C). The results were compared with international standards and showed that the mean values of total hardness and TDS in locations betas, Bezehe and Dolla are ranged from (827.13 ± 5.330), (544.25 ±3.178) ,(782.63 ± 3.257), (930.38 ± 3.545), (675.75± 3.639) ,( 996.25 ± 3.245) mg/L respectivily, were found to be higher than WHO water standards, and unsuitable for drinking use. The results have proven the presence of heavy metal as especially lead, Zn, Cu, and Fe have been containing in the study area. Other parameters were within (WHO) drinking water standards. In conclusion, the other sites of well water sources of the Selevania region are suitable for drinking purposes..

The river Khabur , the life line of more 500 thousand of people, supply water for the important requirements of life. In this study, a total of 2688 water samples were collected from Khabur River, Zakho District. The samples were collected monthly at four different seasons like spring, summer, autumn and winter from March, 2019 to February 2020. The samples were tested for pH, electrical conductivity (EC), total dissolved solids (TDS), total alkalinity (TA), Nitrate (NO3-), Sulfate (SO4 2-) total hardness (TH) magnesium (Mg2+) , Calcium (Ca 2+), phosphate, DO and BOD, according to the standard methods . The results of the chemical and physical characteristic indicate the water river samples with the following parameters. The total mean values of temperature ranged from (14.461± 14.1469) oC . pH varied from (7.831± o.2842). Conductivity ranged from (560. 25 ±110. 805 ) µs/cm) . Total alkalinity varied from (194.19 ± 69.591) mg/l. Total dissolved solid varied from (355.99 ±71.581) mg/l. Dissolved oxygen varied from (8.219 ± o.7989) mg/l. Biochemical oxygen Demand (BOD) ranged from (9.857± 6.0760) mg/l. Total hardness varied from ( 535.02±78.014) mg/l. Calcium (Ca 2+) varied from (409.19 ± 46.875) mg/l. Magnesium (Mg2+) ranged from ( 127.58 ± 46.875) mg/l. Chloride (CL-) varied from ( 26.938 ± 21.2133) mg/l. Nitrate (NO3-) ranged from ( 4.449 ± 2.0327) mg/l. Sulfate (SO4 2-) varied from( 43.24 ±22.479) mg/l. And phosphate ranged from (4.839 ± 1.9139) µ g/l. Gradual increase in total alkalinity and hardness towards the downstream is, due to effluents in Khabur River.Untreated from sewage discharge on river water it cause of high organic matter.Phosphate and Nitrate, at high contents in Khabur River. TDS and EC were found moderate in all locations at Khabur River. The total hardness exceeded the permissible limit in all sites. The (Ca 2+), and (Mg2+), were exceeded permissible limit in all sites. In the present study an attempt had been made to determine the levels of wastewater which ultimately discharged into Khabor River without proper treatment.

The groundwater sources are considered a main source of drinking water in the world. In the present study, the quality of the wells in the 10 villages nearby the city of Zakho was selected for investigation and its suitability for drinking purposes. All the well water samples were analyzed for twelve chemical and physical parameters including dissolved oxygen, total hardness, chloride, total dissolved solids, electrical conductivity, pH, sulfate, and four heavy metals, such as Cu, Fe, Pb, and Zn using standard procedures. The results showed that the value of toxic metals in well water samples were in these ranges: Zn (0.027± 0.004 to 0.005 ± 0.007) ppm; Fe (0.0109 ± 0.035 to 0.183± 0.061) ppm ; Cu (0.001± 0.022to 0.025 ± 0.023) ppm; pb (o.o45 ± 0.015 to 0.069 ± 0.096) ppm. The range of physical and chemical parameters were; pH (7.1 to 8.3), EC (411 to1579 µs/cm), TDS (263 to 1010 mg/L), Total Alkalinity (287 to 584 mg/L), Total hardness (176 to 848 mg/L), Chloride (11.6 to 56.9 mg/L), calcium (80 to 673 mg/L), dissolved oxygen (6.1 to 8.7 mg/L), sulfate (10.3 to 42.5 mg/L) and temperature (17.0 to 23.4°C). The results were compared with international standards and showed that values of total hardness and TDS in most locations were found to be higher than WHO water standards, and unsuitable for drinking use. The results have proven the presence of toxic metal as especially lead, Zn, Cu, and Fe have been containing in the study area. Other parameters were within (WHO) drinking water standards. In conclusion, most of the well water sources of the Selevania region are unsuitable for drinking purposes. Keywords: Heavy metals, well water, drinking water quality, WQI, Zakho, Iraq

Drinking water samples were taken from 18 villages around Zakho district, Kurdistan region, Iraq in annual seasons of 2018 year and chemical analysis of most important water quality parameters were carried out. Water temperature is varied about 13.2◦C to 18.7◦C, four villages have slight acidic water while other 15 locations are tend to be slight alkaline and highest pH value reaches 8.4, electrical conductivity (µs/cm) is over the permissible values of standard drinking water in two villages and high in 4 location while normal in the rest 13 locations, statistical analysis of dissolved oxygen ranges between 6.73 - 8.40 mg/l, statistical analysis of total hardness revealed that the all villages around Zakho district have hard to intensive hard water over 500 mg/l and gives them a slight bitter taste, calcium hardness gives extremely ranges between 72-392 mg/l, and Mg hardness between 39-250 mg/l, statistical analysis of chloride shows is around 250 mg/l which is typical standard for drinking water, SO4 is low and their means located between 18-58 mg/l and NO3 not exceeded 5 mg/l along year months reflecting their purity from pollution. The content of heavy metals Cd, Cu, Mn, Zn, Fe, Ag, Ni, Cr ,Co, are below maximum permissible WHO guidelines and save for drinking while lead is over WHO permissible levels in this rank Mala> Jajoe >Easlam> Bntate> Banee villages and considered a dangerous indicators for drinking water quality in these villages.

Automobile exhausts can contribute to accumulation of Toxic metals in roadside soil. The soil pollution by toxic metals from transportation sources has become a serious environmental threat. The main objective in this research work was to assess the roadside soils contamination with Zn, Cd, Pb, Cu and Ni due to vehicular emissions. The samples were digested using wet method and heavy metals were analyzed using Atomic Absorption Spectrophotometry Technique. Monthly samples were collected from the agriculture soil around roadside during the period December to July 2018. A total of 96 soil samples were collected from different locations of villages around national roadside within Zakho District, Duhok governorate, Iraq. 48 samples were collected at 20 m from the roadway edge and 48 samples were collected at 40 m from the roadway edge. Physical and chemical factors believed to affect the mobility of toxic metals in the soil samples of the study area were tested such as; conductivity, TDS, pH and organic matter. The results showed that the soil pH was from 6.7 to 8.3and the organic matter percentages were from (0.8 to 2.6) EC, from (683 to 1475) µs/cm and TDS was from (437 to 944) mg/l. The soil samples of distance (20 and 40) m from roadside. The results of distance (20 and 40) m from roadside observed that concentration of Pb, Cu, Zn, Cd and Ni was found to vary between (1.1-7. 8 ) (7.7-16.4) (14.2-44.4) (0.10—0.37) (5.8-17.5) (1.0-4.5) (4.4-13.9) (10.1-38.5) (0.03-0.26) (4.7-13.7) mg /Kg respectively. This paper indicated that the heavy metals content decreased with increasing distances along the roadside. The concentrations (mg/kg) of the heavy metals recorded across the sampling sites follow the order: Zn > Ni > Cu > Pb> Cd, of 20 m distance and Zn > Cu> Ni> Pb> Cd, of 40 m distance. Keywords: Agricultural highway, Heavy metals, road-side soil, Automobile exhausts

In this study, lasted for six months from October 2016 to April 2017 in the Akra district of Duhok governorate, we found out the validity of the spring water of the area to be used as drinking water. Indeed, the aim of this study was to assess the validity of the water of spring of the Akra area for human consumption as potable water. The results showed us after the analysis and laboratory examinations (i.e., electrical conductivity (EC), total alkalinity (TA), total dissolved solids (TDS), pH, total hardness (TH), magnesium (Mg2+), Calcium (Ca2+), Dissolved oxygen (DO), and Chloride (CL-)) of all springs water of the region in terms of physical and chemical properties are safe to drink and can be identified as a good source of human consumption. Although there is a difference in some physical and chemical properties in some springs of water in that area, it did not exceed the limits and international standards for drinking water. Therefore, the people of this region can use the water of those springs to drink without fear of any health effects.

This paper intends to assess the well water quality with reference to drinking uses in Nineveh plain district, Northern Nineveh Governorate Iraq. In order to characterize well water quality in Nineveh plain .Twelve wells were selected to represent their water quality. Monthly samples were collected from the wells during February and July 2017. In this study, 72 well water samples were collected and analyzed for various chemical constituents. Sulfate (SO4 2-) ,total alkalinity (TA), total dissolved solids (TDS), total hardness (TH), ( electrical conductivity (EC), pH, Nitrate (NO3-),magnesium (Mg2+) and Calcium (Ca 2+) according to the standard methods, (American Public Health Association (APHA). The results show that pH values of well water range from 7.4 to 8.5 with an average of 7.6-8.4, suggesting their alkaline nature and are considered to be suitable for drinking uses. The levels of Total Dissolved Solids (TDS)range from (243-1228) mg/l, Dissolved Oxygen (DO),range from( 5.4 to 7.5)mg/l , Electric Conductivity (EC) range from (380 to 1920) µs/cm, Chloride range from ( 19.9 to175.3) mg/l , total hardness (TH) range from (186 to 567) mg/l , Sulfate (SO4 2-) range from (8.6 to 133.5) mg/l , Nitrate (NO3-) range from (o.6 to 8.1) mg/l and total alkalinity (TA) range from (84 to 398 mg/l,). The results of analysis showed difference among the wells water quality in the measured parameters, well water quality of Ninevah plain have high dissolved ions due to the dissolved rocks of study area. Total dissolved solids of more than 1000 mg/l, made the Bedara well need to be treated to made taste palatable, the water quality of only in site Bedara well were find hard water more than 500 mg/l .The sulfate, nitrate and chloride concentration were below the guideline for (WHO). The results are compared with standards of World Health Organization (WHO). It was find that some of the water quality parameters were above the permissible limit and some were not. From the results was found that the most of the parameters of Ninevah plain well water are within the permissible limit of World Health Organization (WHO). Keywords: wells, water quality, Physical and chemical parameters, Ninevah plain.

Heavy metals (Pb, Cu, Zn Cd, and Ni) contamination in wheat plants (Triticum aestivum L.) And agricultural soils adjacent to the national highway-with in Zakho district, Iraq has been studied by the analysis of plant and soil sample. Wheat plants were sampled during maturity at 12 locations in July 2017. The result observed that content of five toxic metals was found significantly higher in roots than in the stem parts of wheat plants. On the other hand, the winter wheat transported five toxic metals very weakly from root to stems in the various agricultural soils. The general order for the accumulation of studied metals in wheat plants was found to be Zn > Cu > Ni >Pb >Cd. The mean concentration and standard deviation of toxic metals in the roots and stem of wheat plants varied between (0.1317 ±0.1677) (1.744 ±0.979) (2.857± 1.301) (0.02329 ±0.02149) (1.114 ±0.291) (0.03143 ±0.01952) (0.909 ± 0.854) (0.951±0.769) (0.006 ±0.001718)(0.2957±0.2411) mg/kg,respectively. The results observed that the study sites pollution is mostly due to vehicular emissions. On the other hand, the results observed that vehicular emissions can contribute to accumulation of toxic metals in roadside soil and wheat plants. However concentrations of all the heavy metals obtained were below the maximum permissible limit of toxic metals in plants set by WHO. Keywords: Roadside soil, national high ways, winter wheat, roadside wheat.

Background: Occupational exposures represent complex mixture of genotoxic agents. Benzene is one of the major organic product, people with chronic exposure to this organic product are exposed to many malignant disorders. People who work in Petrol station are consistently exposed to the dangerous components of petroleum through inhalation or direct contact with their skin. Objective: The aim of this study was to evaluate the potential cytogenetic damage and micronuclei frequency associated with occupational exposure to benzene among petrol station workers by using Micronucleus assay. Materials and Methods: The study groups included twenty five occupationally exposed petrol station workers and twenty five age matched controls were recruited and evaluated for genetic damage. Exfoliated Buccal cells were collected from both groups by using the sterile brush. Slides fixed in ethanol and stained with Giemsa stain and 1000 cells were studied by using a light microscope. Statistical analysis for data interpretation performed by Student’s t‑test, and P < 0.05 was considered statistically significant. Results: As compared to control subjects, significant high level of micronuclei frequency was found in the workers exposed to benzene (4.65±2 and 1.22±7 respectively). Period of exposure also showed considerable effects (P<0.05) on micronuclei frequency, while effect of age was non-significant (P>0.05). In this study, both Control and workers with history of Tobacco smoking and alcohol were excluded. Conclusions: The results of our study concluded that benzene have the potential to increase micronuclei frequency in the exposed subjects. The study also suggested that protective strategies should be implemented by the concerned authorities to minimize exposure to fuel. Keywords: Benzene, micronuclei frequency, genotoxic agents, carcinogenic.

Water samples from twenty wells and twenty springs were assessed to determine whether samples from springs and wells have similar concentrations of selected characteristics, including electrical conductivity (EC), total alkalinity (TA), total dissolved solids (TDS), pH, Sulphate (SO4 2-) Nitrate (NO3-), total hardness (TH), magnesium (Mg2+) and Calcium (Ca2+). Comparisons were made between concentrations of chemical and Physical characteristics in water samples from springs and wells within the same aquifer. Samples were collected monthly from the wells and springs during March 2017 to February 2018. The samples were tested for chemical and Physical characteristics according to the standard methods of American Public Health Association. There were significant differences between all data selected from springs and wells except Mg and DO. In addition, no significant difference was found between the mean pH values. The results indicated that the water samples lie within the permissible limits as compared with WHO (World Health Organization) for drinking uses, however some samples of water are without the permissible limit such as EC, TDS, and TH. The spring water samples were found to be better than well water samples. The results showed that eight wells and four springs’ water samples requires treatment for drinking uses. Keywords: Spring water, well water, Soran Mountain District, Kurdistan region, Iraq.

Spring water is the common source of public water supply in most village communities of developing countries such as Duhok city. The water samples were taken from the main water sources where maximum peoples were using them for drinking purpose. The objective of this research is to assess the suitability of spring water quality for drinking purpose at selected sites around Duhok city. Spring water samples were collected from Duske District and have been analyzed for physical and chemical parameters such as, Temperature, total alkalinity, total hardness (TH), total dissolved solids (TDS), electrical conductivity (EC),, pH, Chlorides (Cl-), Nitrite( NO3 -), Dissolved Oxygen (DO), Ca2+, Mg2+ and SO4 2- using American Public Health Association standard methods . The obtained values of each parameter were compared with the standard values set by World Health Organization. Monthly samples were collected from the springs during the period from April to October 2017. The statistical analysis of the experimentally estimated water quality parameters on water samples yielded the range of the variation, mean, standard deviation, co-efficient of variation, The results of analysis carried out showed that the following mean values of, Temperature ranges from(18.900± 1.575) °C to (19.95± 2.02)°C, dissolved oxygen ranges from (6.375±0.330)( 7.725±0.435)mg/l, ( NO3 -), from (1.175± 0.275) to (2.875 ± 1.506)mg/l, sulfate from ( 25.57±2.35) to (69.45±7.07)mg/l, magnesium from (75.00±16.87) to (124.50±15.00)mg/l, Ca2+, from (243.0 ±55.6) to (341.8±48.7)mg/l, total hardness from (300.8±65.1)to( 454.0 ±48.4)mg/l, chloride from( 51.40 ±2.12)to (126.43 ±11.26)mg/l, (TDS), from (359.8 ±34.1) to (822.0 ±87.0) mg/l, (EC) from (562.8±53.3) to (1284.8±135.9) μs/cm and pH from (7.3750 ±0.1500) to (8.1500 ±0.1291). About the total hardness it was found that all of the water quality characteristics were above the permissible limit but within the maximum permissible limit values. Calcium and magnesium were above the permissible limit. The results show that the concentrations of TDS are above the permissible limits at 6 locations. About sulfate, dissolved oxygen and (NO3 -),it was found that all of the water quality parameters were within the permissible limit. The study recommends that most of the spring water needs treatment to protect the households from drinking water. Keywords: spring water, statistical analysis, water quality, Duhok city, Kurdistan region.

In order to characterize the waste water in Duhok valley in Duhok governorate, during 25km, seven sites were selected in Duhok valley, to represent their water quality. Monthly samples were collected from the Duhok valley for the period from, April to September, 2015. The qualitative study of Duhok valley water tested, as considered one of the main sources of water pollution for Musol Lake. The physical and chemical test for water samples are taken from different locations in Duhok valley. To know the degree of pollution, and the impact of self-purification processes to improve water quality before arriving to the Mosul Lake, and the indicated results of the study a lack of dissolved oxygen in the water (DO). And high organic load values, (BOD) and most of the bad qualities during water passage within the city of Duhok, while meat a significant improvement in the quality of water downstream before arriving at the dam Lake, is attributed to the effect of operations of self- purification ability of water. In spite of salinity problems and toxicity, the quality of water is suitable for irrigation crops on both sides of the valley .The all samples were tested for conductivity, TDS, pH, total hardness, chloride, alkalinity, sulfate, BOD, and phosphate, according to the standard methods.