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Control of sea-water intrusion by salt-water pumping: Coast of Oman

Contrôle des intrusions salines induites par pompage d’eau de mer: Cotes d’Oman

Control de la intrusión marina por bombeo de agua salada: costa de Omán

Controlo da intrusão salina por bombagem de água salgada: Costa de Oman

التحكم في تداخل مياه البحر في الخزانات الجوفية بواسطة ضخ المياه المالحة: شاطىء سلطنة عمان

Управление итрузией морской воды путем откачки из пласта соленой грунтовой воды: Побережье Омана

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Abstract

A shallow alluvial coastal aquifer in the Batinah area of Oman, with sea-water intrusion that extends several kilometres inland, has been studied experimentally, analytically and numerically. The water table is proved to have a trough caused by intensive pumping from a fresh groundwater zone and evaporation from the saline phreatic surface. Resistivity traverses perpendicular to the shoreline indicated no fresh groundwater recharge into the sea. Using an analytical Dupuit-Forchheimer model, developed for the plain part of the catchment, explicit expressions for the water table, sharp interface location and stored volume of fresh water are obtained. It is shown that by the pumping of salt water from the intruded part of the aquifer, this intrusion can be mitigated. Different catchment sizes, intensities of fresh groundwater pumping, evaporation rates, water densities, sea level, incident fresh water level in the mountains and hydraulic conductivity are considered. SUTRA code is applied to a hypothetical case of a leaky aquifer with line sinks modeling fresh water withdrawal and evaporation. The numerical code also shows that pumping of saline water can pull the dispersion zone back to the shoreline.

Résumé

Un aquifère cotier alluvial peu profond dans la region de Barinah en Oman, au sein duquel une intrusion saline s’étend sur plusieurs kilometers à l’intérieur des terres, a été étudié de manière expérimentale, analytique et numérique. Il a été montré que la surface piézométrique présente un creux du à des pompages d’eau douce intensifs en nappe souterraine ainsi que par évaporation depuis une nappe superficielle salée. Des profils de résistivité perpendiculaires à la cote ont indiqué qu’il n’y avait pas de perte d’eau douce de l’aquifère vers la mer. A partir de la formulation analytique de Dupuit-Forchheimer, appliquée sur la plaine au sein du bassin versant, il a été possible de déterminer l’expression explicite de la surface de la nappe, de la position de l’interface abrupte entre l’eau douce et l’eau salée, et de la réserve en eau douce. Il est démontré qu’en pompant dans la partie de l’aquifère envahie par l’eau salée, l’intrusion saline peut être atténuée. Différentes valeurs on été considérées concernant la taille des basins versants, l’intensité de pompage d’eau douce, le taux d’évaporation, la densité de l’eau le niveau de la mer, l’altitude de l’eau douce dans la montagne et la perméabilité des terrains. Le code SUTRA est utilisé pour modéliser l’aquifère semi-captif avec des lignes de puits pour prendre en compte les prélèvements et l’évaporation. Le code numérique montre également que [le pompage de] l’eau salée peut faire reculer la zone de mélange vers la cote.

Resumen

Estudios experimentales, analíticos y numéricos se han llevado a cabo en un acuífero costero somero en el área de Batían (Omán), afectado por intrusión marina que se extiende varios kilómetros hacia el continente. Se conoce que el nivel de agua libre se ha deprimido por bombeos intensivos de la zona que contiene agua dulce y por evaporación de la superficie freática salina. Transectas de resistividad perpendiculares a la línea de la costa indican que no hay descarga de agua subterránea dulce hacia el mar. Usando un modelo analítico de Dupuit-Forchheimer, desarrollado para la región plana de la cuenca, y expresiones explícitas para el nivel de agua libre, se obtiene la localización de una interfase brusca y el volumen almacenado de agua libre. Se muestra que el bombeo de agua salada del sector acuífero afectado por la intrusión salina puede mitigar el problema. Se considera el tamaño diferencial de las cuencas de captación, los caudales de bombeo de agua dulce, las tasas de evaporación, las densidades del agua, el nivel del mar, los niveles de agua dulce en las montañas y la conductividad hidráulica. Se aplica el código SUTRA a un acuífero semiconfinado con sumideros lineales que modelan el bombeo de agua dulce y la evaporación. El código numérico demuestra que el agua salina puede desplazar la zona de dispersión hacia la línea costera.

Resumo

Foi estudado experimental, analítica e numericamente um aquífero costeiro aluvial, pouco profundo, na área de Batinah, em Oman, com intrusão salina que se estende vários quilómetros para o continente. Está provado que o nível da água subterrânea sofreu rebaixamento causado pela bombagem excessiva de uma zona de água subterrânea doce e pela evaporação a partir da superfície freática salina. Perfis de resistividade perpendiculares à linha de costa indicaram que não ocorre descarga de água subterrânea doce para o mar. Com o uso de um modelo analítico Dupuit-Forchheimer, desenvolvido para a parte plana da bacia, foram obtidas informações relativas à localização da interface e ao volume de água doce armazenado. Mostra-se que através de bombagem de água salgada na parte salina do aquífero se pode mitigar a intrusão. São consideradas diferentes dimensões de bacia, intensidades de bombagem de água doce subterrânea, taxas de evaporação, densidades da água, nível do mar, nível da água doce subterrânea nas montanhas e condutividade hidráulica. O código SUTRA é aplicado ao aquífero afectado através da definição de linhas de rebaixamento da água doce subterrânea e de evaporação. O código numérico mostra também que a água salgada pode levar a zona de dispersão de volta para a linha de costa.

التحكم في تداخل مياه البحر في الخزانات الجوفية بواسطة ضخ المياه المالحة: شاطىء سلطنة عمان

تمتم دراسة تداخل مياه البحر في الخزان الجوفي الساحلي في منطقة الباطنة بسلطنة عمان والذي يصل الى عدةآيلوميترات بالإختبارات الحقلية، والطرق التحليلية والعددية. ويوجد انخفاض في مستوى المياه الجوفية الحرةبسبب الضخ الزائد من المياه الجوفية العذبة وآذلك بسبب البخر من السطح الحر للمياه الجوفية المالحة. وقد دلتالقطاعات الجيوآهربائية المتعامدة على خط الشاطىء على عدم وجود تدفق للمياه الجوفية العذبة الى البحر.والذي تم انشاؤه للجزء السهلي من ( Dupuit – Forchheimer ) وبإستخدام النموذج التحليلي ديبو فورشميرالحوض المائي، تم استنتاج معادلات للسطح الحر للمياه الجوفية، محل الحد الفاصل بين المياه العذبة والمياهالمالحة وآذلك حجم المياه العذبة المتوفر بالخزان الجوفي. ودلت النتائج أن ضخ المياه المالحة من منطقة التداخلفي الخزان الجوفي يؤدي إلى تقليل التداخل. وقد تم دراسة تأثير مساحة الأحواض المائية، معدلات ضخ المياهالجوفية والبخر، آثافة المياه، منسوب سطح البحر ومنسوب المياه العذبة في المناطق المرتفعة وآذلك معامللدراسة خزان جوفي شبه محصور معرض لسحب المياه(SUTRA) النفاذية. وبإستخدام النموذج العددي سترالنموذج أيضا أن ضخ المياه المالحة يمكن أن يقهقر منطقة (line sinks) الجوفية و تبخرها من نطاق طوليالتداخل إلى خط الشاطىء.

Резюме

Проведено экспериментальное, аналитическое и численное исследование безнапорного пласта, сложенного из аллювиальной породы, расположенного в регионе Батина Султаната Омана и подверженного интрузии морской воды, распространяющейся по пласту на несколько километров от береговой линии. Доказано, что зеркало грунтовых вод имеет впадину, вызванную интенсивными откачками из зоны пресной воды и испарением с фреатической поверхности в зоне интрузии. Измерения электросопротивления, проведенные перпендикулярно береговой линии, доказали, что разгрузка пресных грунтовых вод в океан остутствует. Были получены аналитические решения в рамках модели Дюпюи-Форгхеймера для равнинной части водосборного бассейна. Эти решения дали явные выражения для уровня грунтовых вод, границы раздела пресные-соленые воды в пласте, а также объема пресной воды. Установлено, что за счет откачки соленой грунтовой воды из пласта интрузия может быть уменьшена. Рассмотрены различные размеры области течения грунтовой воды, интенсивности откачек-испарения, плотности жидкостей, уровни грунтовых вод в горной зоне питания равнинной части пласта, коэффициенты фильтрации. Пакет SUTRA использован для расчета фильтрации-массопереноса в пласте с перетоками и линейными стоками, моделирующими откачки. Численные расчеты также показали, что зона дисперсии может быть сдвинута в сторону моря за счет правильной откачки соленых вод.

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Notes

  1. Aflaj (plural of falaj) is a channel system, which provides water for a community of farmers for domestic/agricultural use

Abbreviations

ds(x):

Depths of the water table counted from the ground surface

DF:

Dupuit-Forchheimer

e :

Dimensionless rate of losses from the water table

e 1 :

Dimensionless rate of losses from the saline water table to the left and to the right of the pumping strip

e 2 :

Dimensionless rate of pumping from the saline water table strip

e f :

Dimensionless rate of losses from the fresh water table

e s :

Dimensionless rate of losses from the saline water table

E :

Dimensional rate of losses from the water table

Go(x,ξ 1,ξ 2):

Strack’s ditch function

h(x):

Dupuit-Forchheimer thickness of the fresh saturated zone counted from horizontal bedrock

hs(x):

Dupuit-Forchheimer thickness of the saline saturated zone counted from horizontal bedrock

hf(x):

Dupuit-Forchheimer elevation of the fresh saturated zone counted from msl

H f :

fresh water depth at the inlet of modeled area counted from horizontal bedrock

H 0 :

Fresh water depth at the leftmost boundary of the pumping zone

H 1 :

Fresh water depth at the cross-section of the tip of the intruded saline water tongue

H 2 :

Saline water depth at the cross-section of the triple point

H s :

Saline water depth at the shoreline

k :

Hydraulic conductivity (m/s)

p 1 :

Width of the left strip of saline water uniform evaporation

p 2 :

Width of the strip of saline water pumping

p 3 :

Width of the right strip of saline water uniform evaporation

pf = s1 + s2:

Width of the fresh water zone with pumping

PK:

Polubarinova-Kochina

Q :

Flow rate per unit length (in the direction normal to a vertical cross-section) related to k (m)

Q f :

Flow rate per unit length (in the direction normal to a vertical cross-section) related to k into the fresh water zone coming from the left = total flow rate from the whole fresh water table (m)

s 0 :

Width of the no-pumping and no-recharge fresh water zone

s 1 :

Width of the fresh water zone with pumping but without subjacent intrusion tongue

s 2 :

Width of the fresh water zone with pumping and subjacent intrusion tongue

s 3 :

Width of the saline intruded zone counted from the shoreline to the triple point

s t :

Total width of the study area

TDEM:

Time domain electromagnetic method

TDR:

Time domain reflectometry

V :

Cross-sectional area of the fresh water zone related to porosity (m)

Φd(x):

Discharge potential (m2)

ρ f :

Density of fresh water (kg/m3)

ρs:

Density of saline water (kg/m3)

δ :

ρf /(ρs – ρf)

References

  • Al-Barwani A, Helmi T (2006) Sea water intrusion in a coastal aquifer: a case study for the area between Seeb abd Suwaiq, Sultanate of Oman. Agric Mar Sci 11:55–69

    Google Scholar 

  • Al-Ghilani N (1996) Saline intrusion and groundwater recharge in the Al-Khoud fan, Sultanate of Oman. MSc Thesis, University of Wales, Wales

    Google Scholar 

  • Al-Ismaily A (1998) Coastal aquifer mapping in Oman based on performance evaluation of DC resistivity and TDEM techniques, and the integration of geophysical methods. MSc Thesis, Delft Technical University, The Netherlands

  • Al-Mushikhi AAM (2002) Formation of subsurface water of the southeast Batinah region (Sultanate of Oman) and perspectives of development (in Russian). PhD Thesis, Moscow State Geoexploration University, Russia

  • Al-Shibli SH (2002) Modeling of saltwater intrusion in Wadi Al-Jizi aquifer. MSc Thesis, Sultan Qaboos University, Muscat, Oman

  • Bakker MA (2003) Dupuit formulation for modeling seawater intrusion in regional aquifer systems. Water Resour Res 39(5), 1131. doi:1029/2002WR001710

    Article  Google Scholar 

  • Bear J (1979) Hydraulics of groundwater. McGraw-Hill, New York

    Google Scholar 

  • Calvache ML, Pulido-Bosch A (1997) Effects of geology and human activity on the dynamics of salt-water intrusion in three coastal aquifers in southern Spain. Environ Geol 30:215–223

    Article  Google Scholar 

  • Delta-T Devices (2007) Delta-T Devices, Cambridge, UK. http://www.delta-t.co.uk/. Cited December 2008

  • Geometrics Inc. (2001) Geometrics OhmMapper operation manual. Geometrics, San Jose, CA, USA

  • Guhl F, Pulido-Bosch A, Pulido-Leboeuf P, Gisbert J, Sanchez-Martos F, Vallejos A (2006) Geometry and dynamics of the freshwater-seawater interface in a coastal aquifer in southeastern Spain. Hydrol Sci J 51:543–555

    Article  Google Scholar 

  • Kacimov AR (2001) Analytical solution to a sharp interface problem in a vortex-generated flow. Water Resour Res 37:3387–3391

    Article  Google Scholar 

  • Kacimov AR (2002) Analytical solutions in a hydraulic model of seepage with sharp interfaces. J Hydrol 258:179–186

    Article  Google Scholar 

  • Kacimov AR (2006) Analytical solution and shape optimisation for groundwater flow through a leaky porous trough subjacent to an aquifer. Proc R Soc Lond A 462:1409–1423

    Article  Google Scholar 

  • Kacimov AR, Obnosov YuV (2001) Analytical solution for a sharp interface problem in sea water intrusion into a coastal aquifer. Proc R Soc Lond A 457:3023–3038

    Article  Google Scholar 

  • Kacimov AR, Youngs EG (2005) Steady-state water-table depressions caused by evaporation in lands overlying a water-bearing substratum. J Hydrol Eng ASCE 10(4):295–301

    Article  Google Scholar 

  • Kacimov AR, Obnosov Yu.V, Perret J (2004) Phreatic surface from a near-reservoir saturated tongue. J Hydrol 296:271–281

    Article  Google Scholar 

  • Kacimov AR, Obnosov Yu.V, Sherif MM, Perret J (2006) Analytical solution to a sea water intrusion problem with a fresh water zone tapering to a triple point. J Eng Math 54(3):197–210. doi:10.1007/s10665-006-9030-9

    Article  Google Scholar 

  • Macumber PG (1998) The cable tool program and groundwater flow in the Eastern Batinah alluvial aquifer. Sultanate of Oman Ministry of Water Resources, Muscat, Oman

  • Ministry of Water Resources (1995) Eastern Batinah resource assessment. Progress Report N1. Sultanate of Oman Ministry of Water Resources, Muscat, Oman

  • Padilla F, Cruz-Sanjulian J (1997) Modeling sea-water intrusion with open boundary condition. Ground Water 35:704–709

    Article  Google Scholar 

  • Philip JR (1991) Upper bounds on evaporation losses from buried sources. Soil Sci Soc Am J 55:1516–1520

    Article  Google Scholar 

  • Polubarinova-Kochina PYa (1977) Theory of ground-water movement (in Russian). Nauka, Moscow

    Google Scholar 

  • Segol G (1994) Classic groundwater simulations: proving and improving numerical models. Prentice Hall, Englewood Cliffs, NJ

    Google Scholar 

  • Shammas M (2002) Seawater intrusion in Salalah aquifer, Oman. In: Sherif MM et al (ed) Environmental and groundwater pollution. Swets and Zeitlinger, Lisse, The Netherlands, pp 323–333

    Google Scholar 

  • Sherif MM, Hamza KI (2001) Mitigation of seawater intrusion by pumping brackish water. Trans Porous Media 43:29–44

    Article  Google Scholar 

  • Sherif MM, Singh VP Amer AM (1988) A two dimensional finite element model for dispersion (2D-FED) in coastal aquifers. J Hydrol 103:11–36

    Article  Google Scholar 

  • Simunek J, Sejna M, van Genuchten M Th (1999) The HYDRUS-2D software package for simulating two-dimensional movement of water, heat, and multiple solutes in variably saturated media. Version 2.0, IGWMC-TPS-53, International Ground Water Modeling Center, Colorado School of Mines, Golden, CO, USA

  • Strack ODL (1989) Groundwater mechanics. Prentice Hall, Englewood Cliffs, NJ

    Google Scholar 

  • Van Dam JC (1999) Exploitation, restoration and management. In: Bear J, Cheng A, Sorek S, Ouazar D, Herrera I (eds) Seawater intrusion in coastal aquifers concepts, methods and practices. Kluwer, Dordrecht, The Netherlands, pp 73–125

  • Van Der Veer P (1977) Analytical solution for steady interface flow in a coastal aquifer involving a phreatic surface with precipitation. J Hydrol 34:1–11

    Article  Google Scholar 

  • Verruijt A (1982) Theory of groundwater flow. Macmillan, London

    Google Scholar 

  • Voss CI (1984) A finite-element simulation model for saturated-unsaturated, fluid-density dependent ground-water flow with energy transport or chemically-reactive single-species solute transport: US Geol Surv Water-Resour Invest Rep 81-4369, (rev. 1990), 409 pp

  • Voss CI (1999) USGS SUTRA code: history, practical use and application in Hawaii. In: Bear J, Cheng AHD, Sorek S, Ouzar D, Herrera I (eds) Seawater intrusion in coastal aquifers: concepts, methods, and practices: Kluwer, Dordrecht, the Netherlands, pp 249–313

  • Voss CI, Provost AM (2002) SUTRA, a model for saturated-unsaturated, variable density ground-water flow with solute or energy transport, US Geol Surv Water-Resour Invest Rept 02-4231, 105 pp

  • Weyhenmeyer CE, Burns SJ, Waber N, Macumber PG, Matter A (2002) Isotope study of moisture sources, recharge areas, and groundwater flow paths within the eastern Batinah coastal plain, Sultanate of Oman. Water Resour Res 38(10):1184, pp 2.1–2.22

    Article  Google Scholar 

  • Winston RB, Voss CI (2004) SutraGUI, a graphical user interface for SUTRA, a model for ground-water flow with solute or energy transport, US Geol Surv Open-File Rep 03-285, 114 pp

  • Wolfram S (1991) Mathematica: a system for doing mathematics by computer. Addison-Wesley, Redwood City, CA, USA

    Google Scholar 

  • Wood WW, Sanford WE (2002) Hydrogeology and solute chemistry of the coastal-sabkha aquifer in the Emirate of Abu Dhabi. In: Barth H, Boer B (eds) Sabkha ecosystems, vol 1: the Arabian Peninsula and adjacent countries, Springer, Heidelberg, pp 173–185

  • Yechieli Y, Wood WW (2002) Hydrogeologic processes in saline systems: playas, sabkhas, and saline lakes. Earth Sci Rev 58:343–365

    Article  Google Scholar 

  • Youngs EG (2002) Maintaining fresh-water aquifers over saline water in coastal aquifers. J Agric Sci (Sultan Qaboos University)7:23–28

    Google Scholar 

Download references

Acknowledgements

This study was supported by the joint Sultan Qaboos University -United Arab Emirates University project CL/SQU-UAEU/0/3/02. Comments of two anonymous reviewers are highly appreciated.

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Kacimov, A.R., Sherif, M.M., Perret, J.S. et al. Control of sea-water intrusion by salt-water pumping: Coast of Oman. Hydrogeol J 17, 541–558 (2009). https://doi.org/10.1007/s10040-008-0425-8

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