Bear and others published seawater intrusion in coastal aquifers find, read and cite all the research you need on. Finally, combining expressions 3 and 4 with 6 allows for the determination of the. Freshwater stored in coastal aquifers is particularly susceptible to. Smith abstract the most productive aquifers of the virginia coastal plain are in the potomac formation. The intrusion occurs as a result of the induced flow of seawater into freshwater aquifers originally caused by groundwater development around the coast al barwani and helmi, 2006. Saltwater intrusion into the coastal aquifer has long been recognised as a major concern around the world. Water supplies in the potomac aquifers are impaired, however, by saltwater in some areas. Pdf seawater intrusion in coastal aquifers researchgate. This study simulated the effect of sealevel rise on two coastal aquifers of california. It makes the water from wells salty and undrinkable but some practices are able to prevent this. Saltwater intrusion can naturally occur in coastal aquifers, owing to the hydraulic connection between groundwater and seawater. When you pump out fresh water rapidly, you lower the height of the freshwater in the aquifer forming a cone of depression.
Long distance seawater intrusion through a karst conduit. Saltwater intrusion vulnerability to coastal topography and inland boundary were topics in studies of. Seawater intrusion is often the consequence of freshwater aquifers overexploitation. Sumioka abstract the extent and severity of seawater intrusion was determined using chloride data from 1,289 wells in 14 counties of coastal washington in 1978. March, 2017 stanford scientists map seawater threat to california central coast aquifers. Assessment of seawater mixing in a coastal aquifer by high.
Management of aquifer recharge in lebanon by removing. Tidal influence on seawater intrusion in unconfined coastal aquifers woei keong kuan,1,2 guangqiu jin,3 pei xin,1 clare robinson,4 badin gibbes,5 and ling li1,3 received 16 march 2011. Saltwater intrusion is defined as the inland movement of seawater into aquifers previously occupied by freshwater. Unplanned prolonged overpumping of groundwater is the most important factor in swi that could result in severe deterioration of groundwater quality. Seawater intrusion occurs in some aquifers that are exposed to the ocean offshore. Optimal control of seawater intrusion in coastal aquifers. Abstract studies of seawater intrusionin coastal aquifers have assumed greater importance in recent decades because of t he increased. Three dimensional simulation of seawater intrusion in a regional. Combining genetic algorithms and boundary elements to optimize. Seawater intrusion swi is a widespread environmental problem, particularly in arid and semiarid coastal areas. Coastal aquifers serve as major sources for freshwater supply in many countries. Conduit systems serve to facilitate the rapid transport of seawater many miles inland, and longdistance seawater intrusion has been observed in the karst coastal aquifers in the yucatan peninsula, where a welldeveloped conduit network connects inland sinkholes, fractures, and springs directly to the gulf of mexico,17,18. The seawater contamination of freshwater limits groundwater pumping in coastal areas lacombe and carleton, 1992, werner et al.
The possibility of combining this temporary management approach with other. The exploitation of coastal aquifers always produces a lowering of the water table levels which are protected by the effects in the coastal strip of the sea level. In between these two zones, there occurs a transition zone. Alluvial and coastal quaternary sediments and triassic marbles constitute this complex aquifer. Seawater intrusion and associated processes in a small. Simulation of seawater intrusion in coastal aquifers. Seawater intrusion into coastal aquifers a case study. Seawater intrusion swi occurs when seawater encroaches into the freshwater region of a coastal aquifer, and has long been considered a global issue bear et al.
Seawater intrusion in coastal aquifers concepts, methods. In this project, the focus is on salt water intrusion in coastal groundwater systems, as groundwater is the main resource of. Water supply bulletin 56 1984 describes an investigation of the extent, severity, and longterm trends of seawater intrusion in 14 counties of coastal washington, by comparing chloride data collected in 1978 to chloride concentrations 19661968 and in 1978. Assessment of seawater intrusion potential from sea level. One of ways for prevention of seawater intrusion in coastal aquifer is construction of underground dam. Department of civil, building and environmental engineering dicea, sapienza university of rome, rome, italy. Groundwater from coastal aquifers is a better source for desalination than seawater. The induced gradients usually cause migration of salt water from the sea toward a. Integrative management of saltwater intrusion in poorly. Seawater intrusion in coastal aquifers concepts, methods and. Concepts, methods and practices theory and applications of transport in porous media. In many coastal aquifers, intrusion of seawater has become one of the major. This study was carried out with the objective of assessing the zone of mixing between seawater and groundwater in the coastal aquifer in south of chennai, tamil nadu, india using high.
Assessment of saltwater intrusion along coastal areas of. American associates, bengurion university of the negev. This proposed strategy can be considered as a powerful tool for costeffective management of seawater intrusion in coastal aquifers. This is a pdf file of an unedited manuscript that has been accepted for. Most attention is concentrated on the marine water intrusion into aquifers. Management of seawater intrusion in coastal aquifers. This is a very common and serious phenomenon all over the mediterranean basin, as.
Saltwater intrusion is a major concern in coastal aquifers, particularly in arid and semiarid regions, where. Seawater intrusion into coastal aquifers in washington, 1978. Recent achievements in the field of modeling seawater intrusion into coastal. A costeffective method to control seawater intrusion in. Numerical simulation and effective management of saltwater.
Dynamics of saltwater intrusion processes in saturated. The increasing demand for fresh water in coastal regions is being met by the coastal aquifers. The hydrological, hydrophysical, and hydrochemical aspects of the interaction between marine waters and groundwater in the adjacent land territory as a manifestation of the general process of interaction between surface and subsurface waters. Seawater intrusion is the first cause of contamination of. Effect of groundwater pumping on seawater intrusion in. Seawater intrusion into coastal aquifers in washington, 1978 by n. Seawater intrusion and how to prevent it saltwater intrusion is the induced flow of saltwater into freshwater aquifers due to overdeployment of groundwater. Saltwater intrusion due to groundwater over withdrawal in coastal areas is the only mechanism that causes salination of freshwater. Seawater intrusion is a major problem in urbanized coastal regions of india which is due to over exploitation of groundwater for various purposes. Therefore, appropriate management strategies should be implemented in. The seawater intrusion mechanism in coastal aquifers generally causes the occurrence of a freshwater zone over a seawater zone. As sea water intrusion progresses, existing pumping wells, especially those close. Glover relation of salt water to fresh ground water geological survey watersupply paper 16c a group of short papers, by the individual authors, on the circulation of sea water.
Saltwater intrusion occurs naturally to some degree in most coastal aquifers, owing to the hydraulic. In coastal regions, the groundwater as a primary or sole source of fresh water is. The potential for saltwater intrusion in the potomac. When the extracted volumes are greater than the recharge, even on a local basis, a salinisation process begins in the aquifer as the. Extent of saltwater intrusion sand islands because so little use is made of groundwater from the sand. The development and management of fresh groundwater resources in coastal aquifers are seriously constrained by the presence of seawater intrusion.
The potential for saltwater intrusion in the potomac aquifers of the yorkjames peninsula, virginia by barry s. Similarly by combining the flux equation of the solute with its mass balance. In the first phase of this study we hypothesize that a natural mechanism, identified here as the lifting process, has the potential to mitigate, or in some cases completely reverse, the adverse intrusion effects induced by sealevel rise. Seawater or saltwater intrusion swi is a major environmental threat and management challenge, particularly in areas where there is a history of overexploitation of coastal aquifers. Intrusion of seawater into coastal aquifers is considered one of the most important processes that degrade waterquality by raising the salinity to levels exceeding acceptable drinking standards. As sea water intrusion progresses, existing pumping wells, especially those close to the coast, become saline and have to be abandoned. Origin and dynamics of saltwater intrusion in a regional aquifer. Assessment of seawater intrusion potential from sealevel. Saltwater intrusion is the movement of saline water into freshwater aquifers, which can lead to contamination of drinking water sources and other consequences. Seawater intrusion into coastal aquifers is a major problem in almost all parts of the world.
Assessment of the impact of sealevel rise on seawater. Seawater intrusion due to sea level rise and climate change could significantly contaminate coastal groundwater resources, particularly in florida, the flat lowland state in the united states. Three dimensional simulation of seawater intrusion in a. Groundwater from coastal aquifers is a better source for. Seawater intrusion and salinization processes assesment in a multistrata coastal aquifer in italy. K august 2016 identify saltwater intrusion in coastal aquifer 2. The most important longterm effect of coastal floods is saltwater intrusion swi into coastal aquifers induced by the vertical infiltration of the salt water behind the overtopped andor. Saltwater intrusion has occurred to some degree in many of the coastal aquifers of the united states. In addition, comparisons were made of chloride concentrations in 680 wells sampled both in. Introduction almost all cases of seawater intrusion are recorded were caused by human activities because of intensive water pumping in coastal area.
Depending upon the relative thickness of this transition zone, two approaches are used to model the phenomenon of seawater intrusion in coastal aquifers. Assessment of saltwater intrusion along coastal areas of nellore district, a. Forward rate and extent of saltwater transition zone depends on several factors including. Seawater intrusion sgma usgs ca water science center. Different scenarios are made to investigate the effects of pumping activities on the seawater intrusion problem. Therefore saltwater intrusion should be prevented or at least controlled to protect groundwater resources. Seawater intrusion can have major impacts on water quality in aquifers, rivers and estuaries, and can impact significantly on floodplain and wetland ecosystems. Seawater intrusion and how to prevent it the water. The simulations were carried out with a stateofart, finiteelement, variable. I ncluded in this table are details of the coastal sand dune deposits, although the large resources of groundwater in these are mostly underdevel oped. Tidal influence on seawater intrusion in unconfined. Seawater intrusion into coastal aquifers springerlink.
How significant is the slope of the seaside boundary for. False scientists predict that the worlds water and water cycles will be profoundly affected by climate change. Seawater intrusion processes, investigation and management. The major coastal aquifer systems are shown in figure 1 and are set out in table 1. Continual degradation of groundwater quality in coastal aquifers has become an increasing concern in heavily urbanized regions across the world. The approach presented in this report for the relatively assessment of groundwater extraction and sealevel rise effects on seawater intrusion into coastal aquifers holds potential for wideranging applicability in a variety of hydrogeologic settings. The problem is simulated in the horizontal view of the nile delta aquifer of egypt. Seawater intrusion is the movement of seawater into fresh water aquifers due to natural processes or human activities. Concepts, methods and practices theory and applications of transport in porous media jacob bear, a. One important aspect is mathematical and numerical modelling of salt and fresh water motion. Since saltwater cannot be used to irrigate crops or be consumed by people, saltwater intrusion can be very problematic to coastal communities that rely on fresh groundwater supplies for the livelihood. Introduction over 70% of the worlds populations live in coastal areas.
Seawater intrusion is caused by decreases in groundwater levels or by rises in seawater levels. Because saline water has a higher mineral content than freshwater, it is denser. Investigation of underground dam in coastal aquifers for. Causes global scale rising of sea water level caused by global warming, resulting in increase in the quantity of salt water putting pressure on fresh water aquifers change in precipitation slower recharge rate to replenish the amount of fresh water in the aquifer, making it more susceptible to the inland movement of salt. Seawater intrusion swi is one of the most challenging and widespread environmental problems that threaten the quality and sustainability of fresh groundwater resources in coastal aquifers. Geological survey usgs uses data collection, modeling tools, and scientific analysis to help water managers plan for, and assess, hydrologic issues that can cause undesirable results associated with groundwater use. Management of saltwater intrusion in coastal aquifers in. Pdf saltwater intrusion in coastal aquifers researchgate. Saltwater intrusion is the movement of saline water into freshwater aquifers, which can lead to groundwater quality degradation, including drinking water sources, and other consequences. Seawater intrusion and salinization processes assesment in. Pdf management of seawater intrusion in coastal aquifers.
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