Numerical Simulation of Saltwater Intrusion in Coastal Aquifers

Numerical Simulation of Saltwater Intrusion in Coastal Aquifers

Author: Boutaina Bouzouf

Publisher:

Published: 2015

Total Pages: 71

ISBN-13:

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The modeling of groundwater in costal aquifers is an important and difficult issue in water resources. The primary difficulty resides in efficient and accurate simulation of the movement of the saltwater front. This thesis is devoted to the sharp interface numerical study of one and two dimensional of seawater intrusion into coastal aquifers. The Finite Volume method is adopted here to solve the set of simultaneous diffusion differential equations describing the motion of saltwater and freshwater separated by a sharp interface. These diffusion equations are based on the Dupuit approximation and are obtained from integration over the vertical dimension. The one dimensional Finite Volume model is first being validated using academic test case studies with known close from solutions. The second purpose of this study is to compare two dimensional numerical methods, Finite Volume method and Sharp model based on Finite Difference method when applied to a Llobregat aquifer, in Barcelona, Spain. Both methods are using the same mathematical formulation for the sharp interface. The comparison between both methods indicates that Finite Volume method provides predictions closer to the observed results.


Seawater Intrusion in Coastal Aquifers

Seawater Intrusion in Coastal Aquifers

Author: Jacob Bear

Publisher: Springer Science & Business Media

Published: 2013-03-09

Total Pages: 652

ISBN-13: 9401729697

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Coastal aquifers serve as major sources for freshwater supply in many countries around the world, especially in arid and semi-arid zones. Many coastal areas are also heavily urbanized, a fact that makes the need for freshwater even more acute. Coastal aquifers are highly sensitive to disturbances. Inappropriate management of a coastal aquifer may lead to its destruction as a source for freshwater much earlier than other aquifers which are not connected to the sea. The reason is the threat of seawater intrusion. In many coastal aquifers, intrusion of seawater has become one of the major constraints imposed on groundwater utilization. As sea water intrusion progresses, existing pumping wells, especially those close to the coast, become saline and have to be abandoned. Also, the area above the intruding seawater wedge is lost as a source of natural replenishment to the aquifer. Despite the importance of this subject, so far there does not exist a book that integrates our present knowledge of seawater intrusion, its occurrences, physical mechanism, chemistry, exploration by geo physical and geochemical techniques, conceptual and mathematical modeling, analytical and numerical solution methods, engineering measures of combating seawater intrusion, management strategies, and experience learned from case studies. By presenting this fairly comprehensive volume on the state-of-the-art of knowledge and ex perience on saltwater intrusion, we hoped to transfer this body of knowledge to the geologists, hydrologists, hydraulic engineers, water resources planners, managers, and governmental policy makers, who are engaged in the sustainable development of coastal fresh ground water resources.


Numerical Analyses of Potential Losses of Freshwater Resources in Coastal Aquifers Caused by Global Climate Change Using an Appropriate Boundary Condition

Numerical Analyses of Potential Losses of Freshwater Resources in Coastal Aquifers Caused by Global Climate Change Using an Appropriate Boundary Condition

Author: Jun Mizuno

Publisher:

Published: 2008

Total Pages: 98

ISBN-13:

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Abstract: Coastal regions face various hydrological problems including saltwater intrusion in the aquifers. One of the processes affecting saltwater intrusion is sea-level rise caused by global climate change. Sea-level rise could enhance saltwater intrusion and cause a decrease in freshwater resources from aquifers. The boundary condition with variable mass flux and constant pressures, the Dynamic Mass Flux Boundary (DMFB), was examined for the numerical simulation of saltwater intrusion in coastal aquifers. The results showed the DMBF to be more accurate than the typically-used Dirichlet boundary. Using the DMFB, the effects of potential sea-level rise on saltwater intrusion and the freshwater supply in coastal aquifers with heterogeneous permeability fields were investigated. The impact of pumping was also examined in conjunction with the effects of sea-level rise. It is found that heterogeneous permeability fields greatly enhanced the saltwater intrusion process under the combined effects of sea-level rise and pumping.