Studies of Al Asfar and Al Uyoun Evaporation Lakes Water Quality and the Potential of Its Reuse in Agriculture Activities, Al Hassa Area, KSA

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1 JKAU: Met., Env. & Arid Land Agric. Sci., Vol. 22, No. 3, pp: (2011 A.D. /1432 A.H.) DOI: / Met Studies of Al Asfar and Al Uyoun Evaporation Lakes Water Quality and the Potential of Its Reuse in Agriculture Activities, Al Hassa Area, KSA A.S. El Mahmoudi, M.A. Massoud, Y.Y. Al-Dakheel and A.H.A. Hussein Water Studies Center, King Faisal University, Al Hofuf, Saudi Arabia Abstract. There is a growing concern in the Kingdom of Saudi Arabia to exploit water resources of acceptable quality to meet demands in domestic, industrial, and agricultural sectors. The agricultural water need constitutes approximately 85% of the total demand. Various alternative supplies to meet these demands are considered: Surface water, renewable groundwater resources, treated wastewater, desalinated water, and nonrenewable groundwater. Al Hassa Oasis is one of the main and old agricultural centers in Saudi Arabia. An irrigation network of 1, 450 km of concrete canals and drainage network were put into operation in The project delivers 328 million m 3 of spring water for about 22, 000 farms. The excess drainage water is collected by earthen drainage network and discharged into two evaporation lakes, which are Al Asfar and Al Uyoun. Such evaporation lakes (wet lands) are important link between water and land ecosystems. They provide habitats and refuges for wildlife, flood protection and contribute to abatement of impact of pollution and promoting groundwater recharge. The aim of this study is to investigate the water quality of these two evaporation lakes of Al Asfar and Al Uyoun and to study the potential of its reuse in agriculture activities at Al Hassa Oasis. Remote sensing, hydrogeological, chemical studies and Geographical Information Systems (GIS) are implemented to achieve the objectives of this study. For Al Asfar Lake, fourteen samples from surface water and the isolated water ponds and twenty samples of soil water from the area characterized by shallow water table ( 20 cm depth) have been collected in May to June, For Al Uyoun Lake, thirty five samples from surface water and the isolated water ponds and eight samples of soil water have been collected in March to April, Through chemical analyses, the major and minor ions content of soil pore water, surface water and sabkha soil samples were assessed. ArcGIS software and 67

2 68 Studies of Al Asfar and Al Uyoun Evaporation Lakes satellite image processing software (ERDAS Imagine) were used for the integration of the output parameters of this study and for visualization of their spatial distribution. The results indicate that surface water of Al Asfar and Al Uyoun lakes are characterized by relatively low salinity and then encourage to re-treat this considerable quantity of water and to reuse it in agricultural purposes. This will lead to minimization of the sabkha extension, mitigation of its impact on the nearby farms of Al Hassa oasis and mitigation of aquifer recharge with high saline water and optimization of water use of this surface water body in this arid environment. The results of this study are important in any future development of the Al Asfar and Al Uyoun areas in planning. 1. Introduction Water resources are essential and play a significant role in the development processes. The Kingdom of Saudi Arabia (KSA) is known by its arid conditions and limited renewable freshwater resources. Surface water in KSA is very limited and of a little significance in the water budget. To meet the increasing water demands in domestic, industrial, and agricultural sectors, various alternative supplies are considered: Surface water, renewable groundwater resources, treated wastewater, desalinated water, and non-renewable groundwater. Fresh water supply in arid regions is limited due to scarce precipitation and high evapotranspiration. When the limited supply is coupled with increasing demand for fresh water in these regions due to rapid population growth, it necessitates optimal development and management of water resources. Al Hassa Oasis is one of the main and old agricultural centers in Saudi Arabia. Al Hassa oasis with an area of 20,000 hectares is located 70 km west of the Arabian Gulf (Fig. 1). An irrigation network of 1,450 km of concrete canals and drainage network were put into operation in 1971 (Abderrhman and Bader, 1992). This irrigation project delivers 328 million m 3 of groundwater for about 22, 000 farms. Nowadays this amount of water is increased due to the discharge of treated wastewater from Al Hofuf sewage station into the irrigation network.

3 A.S. El Mahmoudi, et al. 69 Al Asfar Study area Fig. 1. Base map of Al Hassa Region and the location of the study area. Al Hassa drainage water is collected by 1641 earthen lateral open canals having depths of about 1 m. The collected drainage water in the eastern sector of the project flows from the laterals to three sub main drainage canals which are connected to main drainage canal D2 (Fig. 2). The collected water in this drainage flows towards Al Asfar Evaporation Lake at 13 km to the east of Al Hassa Oasis. The drainage water in the northern sector flows from the laterals to six sub main drainage canals, which are connected to main drainage canal D1. Drainage water in D1 flows towards Al Uyoun Evaporation Lake outside Al Hassa Oasis, 52 km north of Al Hofuf. The water remains in the evaporation lakes during winter season to be used to supply cattle with drinking water and for aquifer recharge. From December until April each year, the agricultural drainage water overflows from the northern lake through small waterways into the Arabian Gulf, (Abderrhman and Bader, 1992).

4 70 Studies of Al Asfar and Al Uyoun Evaporation Lakes Fig. 2. Main drainage system of Al Hassa irrigation and drainage project. The main salient morphologic features of Al Asfar and Al Uyoun Lakes are wet lands (Fig. 3), sabkhas and sand dunes. Salt tolerant vegetation (halophyte) is found in some of the less salt affected sabkha areas. The area is characterized by widespread growth of halophyte shrubs associated with a very thin salt crust on the sabkha surface. Al Asfar Lake Al Uyoun Lake Fig. 3. Parts wet lands of Al Asfar and Al Uyoun lakes.

5 A.S. El Mahmoudi, et al. 71 Hydrogeology and hydrochemistry of groundwater of Al Hassa area have been reported in many studies (Etewy, et al., 1983; Al- Mahmoud, 1987; Abderrahman, 1988; Edgell, 1989; Al Dakheel and Al Safarjalani, 2005; Al Safarjalani and Almadini 2007; Al-Zarah, 2007 and 2008; and Al Dakheel, 2009). The aim of this study is to investigate the water quality of these two evaporation lakes of Al Asfar and Al Uyoun, and to study the potential of its reuse in agriculture activities at Al Hassa Oasis, Al Hassa area, KSA. 2. Materials and Methods Multi-date landsat-5 TM imageries of years 1987, 1993, 1998 and 2000 and SPOT imageries of 2007 of the study area have been processed and analyzed to investigate the dynamics of both water ponds and the associated sabkha with time at Al Asfar and Al Uyoun lakes areas. For Al Asfar Lake, fourteen samples from surface water and the isolated water ponds and twenty samples of soil water from the area characterized by shallow water table ( 20 cm depth) have been collected in May to June, For Al Uyoun Lake, thirty five samples from surface water and the isolated water ponds and eight samples of soil water have been collected in March to April, 2008, (Fig. 4 (a and b)). The latitude and longitude of the soil and water samples coordinates were measured by using high accuracy differential GPS. The ph and the electrical conductivity (EC) were measured for the collected water samples. Sodium and potassium were determined by flame photometry according to Jackson (1973). Calcium and magnesium were determined by atomic absorption spectrophotometer according to Carter (1993). Soluble carbonates and bicarbonates were determined volumetrically in the soil paste extract by titration against 0.01 N hydrochloric acid using phenolphthalein and methyl orange as indicators according to Jackson (1967). Soluble chlorides were determined by titration with 0.01 N silver nitrate solution and potassium chromate as indicator according to Richards (1954). Sulphate was determined turbidimetrically with barium chloride as described by Jackson (1973). The concentrations of NO 3 - were determined in water samples according to Norman, et al. (1985) method. ArcGIS software and satellite image processing software (ERDAS Imagine) were used for the integration of the output parameters of this study and for visualizes their spatial distribution.

6 72 Studies of Al Asfar and Al Uyoun Evaporation Lakes Al01 Surface water sample Location & No. Als1 Soil water sample Location & No Wet Land ALS12 ALS ALS AL01 AL02 ALS2 ALS8 AL06 AL05 ALS9 ALS6 AL AL03 ALS3 ALS4 ALS10 AL07 AL08 AL04 ALS7 ALS14 ALS13 ALS D2 ALS5 ALS1 AL014 AL013 ALS20 ALS15 AL09 AL010 AL012 ALS Fig. 4(a). Base map of the surface and soil water samples, Al Asfar lake area, Al Hassa, KSA U03 US1 U02 D1 U05 U04 US2US3 U01 U06 US4 U07 U035U034 US5 U033 U08 U032 U031 Aramco Road U09 U030 U011 U012 U010 U029 U013 U028 U021 U015 U014 U025 US6 U023 U024 U022 US8 U027 U026 U016 U017 Al Uqair Road U018 U019 U020 US7 U01 Surface water sample Location & No. US1 Soil water sample Location & No. Wet Land Fig. 4(b). Base map of the surface water and soil water samples of Al Uyoun evaporation lake, Al Hassa area, KSA. 3.1 Remote sensing Investigations 3. Results and Discussion In this study, Landsat -5 TM imageries with seven bands of years 1987, 1993, 1998 and 2000 beside SPOT imageries of 2007 of the study area have been geo-referenced, visually interpreted and analyzed to identify different geomorphic units of Al Asfar and Al Uyoun Lakes

7 A.S. El Mahmoudi, et al. 73 environments. The digital elevation models (DEM) of the study areas were also processed and analyzed. The Elevation Data collected using the GPS system have been used for constructing Digital Elevation Models (DEM) for Al Asfar and Al Uyoun Lakes (Fig. 5 (a and b)). These maps facilitated the interpretation of the chemical analysis as discussed below. From the map shown in Fig. 5 (a), it is noticed that the elevation of Al Asfar area is decreasing toward east and ranges from 112 m above mean sea level in the southwest to 92m above mean sea level in the northeast. While, from the map shown in Fig. 5 (b), it is noticed that the elevation of Al Uyoun area is decreasing as well toward east and ranges from 80m above mean sea level in the west to 55m above mean sea level in the east. The processed landsat-5 TM and SPOT Imageries for Al Asfar Lake area (Fig. 6 a) indicated that there is a general increment in both the sabkha and wet land areas extent with the passage of time (sabkha and wetlands in 1987 vs. sabkha and wetlands in 2000), (Fig. 6 a) Elevation (m) D2 Wet Land Fig. 5(a). Digital elevation model map of Al Asfar area, Al Hassa, KSA.

8 74 Studies of Al Asfar and Al Uyoun Evaporation Lakes Elevation (m) D Aramco Road Al Uqair Road Sample Location & No. Wet Land Fig. 5(b). Digital elevation model map of Al Uyoun evaporation lake area, Al Hassa, KSA. The direction of increment is related to relief where increased sabkha areas have taken place in low relief areas where groundwater rose and pushed salt to the surface. On the other hand, the processed landsat-5 TM and SPOT Imageries of Al Uyoun area (Fig. 6 b) indicated that there is a general decrease in both the sabkha and wet land areas extent with the passage of time (sabkha and wetlands in 1987 vs. sabkha and wetlands in 2000 and in 2007). The reason behind that is due to Hassa Irrigation and Drainage Authority (HIDA) which is recently retreating water of Drain one (D1) and reusing the treated water for irrigation purposes at Al Hassa Oasis. Fig. 6(a). The processed landsat-5 TM Imageries (in years of 1987 and 2000) and SPOT (in year 2007) for Al Asfar area.

9 A.S. El Mahmoudi, et al. 75 Fig. 6 (b). The processed landsat-5 TM Imageries (in years of 1987 and 2000) and SPOT (in year 2007) for Al Asfar area. 3.2 Chemical and Hydrochemical Investigations The water samples were analyzed for their chemical properties; hydrogen ion concentration (ph), electrical conductivity (EC), and then total dissolved salts (T.D.S.) was calculated and for major constituents (Na +, Ca ++, K +, Mg ++, Cl -, SO 4 --, HCO 3 - and NO 3 - ). Table 1 summarizes

10 76 Studies of Al Asfar and Al Uyoun Evaporation Lakes the statistical analysis of chemical properties and for major constituents of the collected surface water and pore water samples for both Al Asfar and Al Uyoun areas. From this table, it could be noticed that, for Al Asfar samples the major cations are in order Na +, Mg ++, Ca ++ and K +, while for Al Uyoun samples the major cations are in order Na +, K +, Ca ++ and Mg ++. The major anions for both Al Asfar and Al Uyoun samples are in order: Cl -, SO 4 --, HCO 3 - and NO 3. The carbonate content is so small that it was undetected as the maximum value of ph is not more than 8.3 which is the threshold at which these ions start to form for both soil and water samples (Stumm and Morgan, 1981). ph was measured for water samples. Figure 7 (a and b) shows the spatial distribution map of ph values for water samples of Al Asfar and Al Uyoun lakes. The ph values of Al Asfar water samples varied between 7 and 8.3. While the water samples of Al Uyoun had ph values ranging between 6.85 and It could noticed that ph values of Al Uyoun area (Fig. 7 b) are increasing northward and the samples located to the northeast corner have the maximum ph values. Also, the area around the mouth of Drain One (D1) is characterized by high ph values. Generally, all the water samples of both Al Asfar and Al Uyoun areas indicate a slightly alkaline character with very narrow ph ranges. Table 1. Statistical analysis for chemical analysis for the major cations and anions for Al Asfar and Al Uyoun surface water and for pore water samples. Area Al Asfar Samples Analysis Values ph EC (ds/m) TDS (ppm) Major Cations (ppm) Na + Ca ++ K + Mg ++ Cl - SO 4 -- Major Anions (ppm) HCO 3 - Minimum Maximum Mean SD* N O3 - Minimum Al Uyoun Samples Maximum Mean SD* *Standard Deviation

11 A.S. El Mahmoudi, et al U03 US1 U02 D1 U05 U04 US2US3 U01 U06 US4 U07 US5 U035U034 U033 U08 U032 U031 Aramco Road U09 U030 U011 U012 U010 U029 U013 U028 U021 U015 U014 U025 US6 U023 U024 U022 US8 U027 U026 U016 U017 U018 Al Uqair Road U019 U020 US a) Al Asfar b) Al Uyoun Fig. 7. Distribution map of the ph content for the water of Al Asfar and Al Uyoun Lakes, Al Hassa area, KSA. The total salinity of surface water and pore water samples of Al Asfar area ranged from 7,624 to 81,840 ppm with a mean value of 32,383.5 ppm (Table 1).The relatively low values of total salinity are belonging to the surface water samples from the main lake of Al Asfar (Fig. 8 a and Fig. 9 a), where the irrigation drainage water of low salinity is discharged to the lake through drainage canal D2), while the high values are belonging to surface waters samples collected from isolated ponds around the main lake (where high evaporation and more salt is concentrated). For Al Uyoun Lake, the total salinity of surface water and pore water samples ranged from 5992 to 79,664 ppm with mean value of 32,903 ppm, (Table 1). The relatively low values of total salinity are belonging to the surface water samples from the main lake of Al Uyoun (Fig. 8 b). This relatively low salinity values of the surface water of Al Asfar and Al Uyoun Lakes encourage to re-treat these water and to reuse it in agricultural purposes, this will lead to minimize the sabkha extension, to mitigate its impact on the nearby farms of Al Hassa oasis and to mitigate aquifer recharge with high saline water and to optimize the water use of this surface water body in this arid environment. The salt content of soil water for the collected samples depends on the distance from the main water body of Al Asfar lake, i.e. the nearest to the lake, the less of salt content. The soil water salinity at the margins of Al Uyoun Lake ranges from 26,312 ppm to 71,400 (Fig. 8 b). The salt content of soil water for the collected samples as well depends on the distance from the main water body of Al Uyoun lake, i.e. the nearest to the lake, the less of salt content. The soil water salinity at the margins of Al Asfar Lake ranges

12 78 Studies of Al Asfar and Al Uyoun Evaporation Lakes from less than 10,000 ppm (see for example salinity of samples Nos. Als1, Als5 and Als7) to about 80,000 ppm (see for example salinity of samples Nos. Als 6, Als11 and Als19), (Fig. 8 a &9 b) TDS (ppm) TDS (ppm) U03 US1 U02 U05 U06 U04 US2US3 US4 U07US5 U033 U08 U032 U031 Aramco Road U013 U015 U014 U025 US6 U023 U024 U026 U011 U022 US8 U012 U027 U010 U028 U021 U029 U09 U030 U016 U017 U018 U020 U019 US AL01 AL02 ALS2 ALS8 AL06 AL05 ALS9 ALS3 ALS4 ALS10 AL07 AL03 ALS12 ALS11 ALS6 AL04 ALS7 AL08 ALS14 ALS13 AL011 ALS19 ALS Al01 Surface water sample D1 U01 U035 U034 Al Uqair Road 5000 U01 Surface wate Us1 Soil water sa D2 ALS5 ALS1 AL013 AL014 ALS20 ALS15 AL09 AL010 AL012 ALS17 Als1 Soil water sample Lo Wet Land W b) Al Uyoun a) Al Asfar Fig. 8. Spatial Distribution map of the total salinity or the water of Al Asfar and Al Uyoun Lakes, Al Hassa area, KSA TDS (ppm) AL01 AL02 AL03 AL04 AL05 AL06 AL07 AL08 AL09 AL010 AL011 AL012 AL013 AL014 Sample No. Fig. 9(a). Total Dissolved Salinity of surface water samples of Al Asfar Lake, Al Hassa area, KSA TDS (ppm) ALS1 ALS2 ALS3 ALS4 ALS5 ALS6 ALS7 ALS8 ALS9 ALS10 ALS11 ALS12 ALS13 ALS14 ALS15 ALS16 ALS17 ALS18 ALS19 ALS20 Sample No. Fig. 9(b). Total Dissolved Salinity of soil water samples of Al Asfar Lake, Al Hassa area, KSA.

13 A.S. El Mahmoudi, et al. 79 The soil water under this sabkha is more saline than the normal sea water in these so arid environments. It is worthy to mention that the contour pattern of the constructed spatial distribution maps for the major cations of water samples for Al Asfar and Al Uyoun (Fig. 10 (a and b)) are similar to that of TDS shown in Fig. 8 (a and b). However, in case of anions the contour pattern for chloride and sulphate have the similar pattern of TDS while for both Bicarbonate and Nitrate have a different pattern (Fig. 11(a and b)). The bicarbonate in this water is thought to be derived partly from the outcrops of Neogene carbonate ridges originated under marine conditions Na (ppm) Ca (ppm) ALS12 ALS ALS12 ALS ALS ALS AL01 AL02 ALS2 ALS8 AL06 AL05 ALS9 ALS3 ALS4 ALS10 AL07 AL03 ALS6 AL08 AL04 ALS7 ALS14 ALS13 AL011 ALS Al Surface water sample Location AL01 AL02 ALS2 ALS8 AL06 AL05 ALS9 ALS3 ALS4 ALS10 AL07 AL03 ALS6 AL08 AL04 ALS7 ALS14 ALS13 AL011 ALS D2 ALS5 ALS1 AL014 AL013 ALS20 ALS15 AL09 AL010 AL012 ALS17 Als1 Soil water sample Location & No Wet Land D2 ALS5 ALS1 AL014 AL013 ALS20 ALS15 AL09 AL010 AL012 ALS17 Al01 Surface water sample Location & No Als1 Soil water sample Location & No. Wet Land Na Ca ++ K + Mg ++ Fig. 10(a). Distribution maps of the major cations concentration for the surface water and soil water of Al Asfar area, Al Hassa, KSA.

14 80 Studies of Al Asfar and Al Uyoun Evaporation Lakes Ca ++ Na + Mg ++ Fig. 10(b). Distribution maps of the major cations concentration for the surface water and soil water of Al Uyoun area, Al Hassa, KSA. K + SO 4 -- Cl NO 3 HCO 3 Fig. 11 (a). Distribution maps of the major anions concentration for the surface water and soil water of Al Asfar area, Al Hassa, KSA.

15 A.S. El Mahmoudi, et al. 81 SO 4 -- Cl NO 3 HCO 3 Fig. 11(b). Distribution maps of the major anions concentration for the surface water and soil water of Al Uyoun area, Al Hassa, KSA. 4. Conclusions Integration of the processed Landsat TM imagery and chemical analysis contributes to a better understanding of the environment of Al Asfar and Al Uyoun Lakes, Al Hassa area. The processed landsat-5 TM and SPOT imageries indicated there is a general increment in both sabkha and wet land areas extent with the passage of time at Al Asfar Lake area. While, for Al Uyoun lake, there is a general decrease in both the sabkha and wet land areas extent with the passage of time and this is attributed to the recycling of Drain one (D1) water by Hassa Irrigation and Drainage Authority (HIDA) and is used for irrigation purposes at Al Hassa Oasis. The hydrochemical analysis revealed that the surface water of Al Asfar and Al Uyoun are characterized by a relatively low salinity and then re-treating and reusing of this water in agricultural purposes will lead to minimize the sabkha extension, to mitigate its impact on the nearby farms of Al Hassa oasis, to mitigate aquifer recharge with high

16 82 Studies of Al Asfar and Al Uyoun Evaporation Lakes saline water and to optimize the water use of this available surface water body in this arid environment. The evaporation condition prevailing in the present study and the absence of continuous recharge from the main drainage (D1 and D2) led to the concentration of highly saline lagoon water. A monitoring system for water levels and quality at Al Asfar and Al Uyoun Lakes should be established, maintained and updated. Acknowledgments The authors would like to express their sincere appreciation to Deanship of Scientific Research, King Faisal University for the financial support of this study under fund grant No Special thanks go to Mohamed Al Kulaib and Mohamed Al Farij for their assistance in the field activities and in the laboratory measurements of this study. References Abderrahman, W.A. and Bader, T.A. (1992) Remote-sensing application to the management of agricultural drainage water in severely arid region - A case study, J. Remote Sensing of Environment, 42: Abderrahman, W.A. (1988) Water management plan for the Al-Hassa Irrigation and Drainage Project in Saudi Arabia, Agric. Water Manage, 13: Al Dakheel, Y.Y. and A.M. Al Safarjalani (2005) Study of the historical pattern of changes in water quality of Al Hassa Oasis springs, Egypt. J. of Productivity and Development, 10 (2): (in Arabic). Al Dakheel, Y.Y. (2009) Spatial modeling for groundwater salinity: Neogene aquifer, Al-Hassa, Saudi Arabia, J. Environmental Hydrogeology, 17: 1-9. Al Safarjalani, A.M. and A.M. Almadini, (2007) Effect of spatial variations in chemical properties of irrigation groundwater at Al-Hassa Oasis, Kingdom of Saudi Arabia, J. for Agricultural and Scientific Research, Damascus University, 23(1): Al-Mahmoud, M.J. (1987) Hydrogeology of Al Hassa Oasis, M. Sc. Thesis, King Fahad University of Petroleum and Minerals, Dhahran, Saudi Arabia. Al-Zarah, A. I. (2007) Hydrogeochemical processes of Alkhobar aquifer in Eastern Region, Saudi Arabia, J. Applied Sciences, 7 (23): Al-Zarah, A. I. (2008) Chemistry of groundwater of Al-Ahsa Oasis Eastern Region Saudi Arabia and its predictive effects on soil properties, Pakistan J. of Biological Sciences, 11(3): Carter, M.R. (1993) Soil Sampling and Methods of Analysis. Canada Society of Soil Science, Lewis Publishers. Edgell, H.S. (1989) Geological framework of Saudi Arabia groundwater resources, J. of King Abdulaziz University: Earth Sciences, 3: Etewy, H., Assed, M., Al-Barrak, S. and Turjoman, A. M. (1983) Water quality and soil characteristics as related to irrigation and drainage in Al-Hassa area, In: The Sixth Conference on the Biological Aspects of Saudi Arabia, King Abdulaziz University, Jeddah, KSA, March 1-3, 1983, pp: Jackson, M.L. (1973) Soil Chemical Analysis, Prentice-Hall, Inc. India.

17 A.S. El Mahmoudi, et al. 83 Jackson, M.L. (1967) Soil Chemical Analysis, Prentice Hall, Inc., Engle Wood Cliff., USA. Norman, R.J., Edberg, J. C. and Stucki, J. W. (1985) Determination of nitrate and nitrite in soil extracts by ultraviolet spectrophotometry, Am. J. Soil Sci. Soc., 49: Richards, L.A. (1954) Diagnosis and Improvement of Saline and Alkali Soils, Agriculture Handbook no. 60, United States Department of Agriculture, Washington. Stumm, W. and Morgan, J.J. (1981) Aquatic Chemistry: An Introduction Emphasizing Chemical Equilibria in Natural Waters, Join Willey, New York.

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19 A.S. El Mahmoudi, et al. 85 ) ( ) (