Seawater intrusion is the first cause of contamination of. Saltwater intrusion is the induced flow of seawater into freshwater aquifers primarily caused by groundwater development near the coast. In this study, abstraction, desalination and recharge method and seawat numerical model are used to investigate seawater intrusion repulsion in a hypothetical twodimensional coastal aquifer to understand the relation of seawater intrusion with abstraction, desalination and recharge parameters i. The cartoon below illustrates the interaction between fresh and sea water in coastal aquifers. The pattern of flow described in this paper is based on the assump tion that the salt water is essentially static. Assessment of seawater intrusion potential from sea level. About 60 percent of coastal aquifers are contaminated by. The rapid growth of the population and economy in the coastal regions has been consuming a tremendous amount of groundwater resources and has increased the extent of seawater intrusion.
In many coastal aquifers, intrusion of seawater has become one of the major constraints imposed on groundwater utilization. Experimental saltwater intrusion in coastal aquifers using. 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. Abstract studies of seawater intrusionin coastal aquifers have assumed greater importance in recent decades because of t he increased. Seawater intrusion can have major impacts on water quality in aquifers, rivers and estuaries, and can impact significantly on floodplain and wetland ecosystems. Experimental saltwater intrusion in coastal aquifers using automated image analysis.
Dec 12, 2009 these developed methodologies are tested for an illustrative coastal aquifer study area. Proceedings of the first international conference on saltwater intrusion and coastal aquifers monitoring, modeling and. Mapping saline water intrusion into the coastal aquifer with. Recent achievements in the field of modeling seawater intrusion into coastal. Groundwater from coastal aquifers is a better source for. Department of civil, building and environmental engineering dicea, sapienza university of rome, rome, italy. Some of these impacts are already being felt today climate change is projected to cause longer more severe droughts and shorter more intense periods of rain.
Aug 04, 2014 in the central coast has caused groundwater levels to decline, allowing seawater to move into the coastal aquifers. Saltwater intrusion in agricultural fields in eastern. In addition, comparisons were made of chloride concentrations in 680 wells sampled both in. Abstract 1 studies of seawater intrusion in unconfined coastal aquifers typically neglect oceanic oscillations such as tides and assume a static seaward boundary condition defined by the mean sea level. 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. Freshwater stored in coastal aquifers is particularly susceptible to degradation. One of the biggest challenges facing southern californias groundwater supply is overdraftwithdrawing more. Jul 06, 2016 with time, seawater is introduced into the aquifer, reaching its wells and affecting water quality. Coastal aquifers serve as major sources for freshwater supply in many countries. Thus, once established, the fresh water does not quickly waste away. A multidisciplinary approach to studying the nature and occurrence of saline groundwater in the gulf islands, british columbia, canada. Analytical models of contaminant transport in coastal aquifers. Dausman chapter 46 of section a, groundwater book 6, modeling techniques groundwater resources program techniques and methods 6a46 u. Simulation of seawater intrusion in coastal aquifers.
When the extracted volumes are greater than the recharge, even on a local basis, a salinisation process begins in the aquifer as the. Hamill school of planning, architecture, and ivil engineering, queens university elfast, david keir building, stranmillis road, belfast bt95ag, uk. Seawater intrusion into coastal aquifers a case study. Seawater intrusion can be caused by overpumping in sensitive portions of coastal aquifers. 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. Saltwater can contaminate freshwater aquifers when one or more of the following mechanisms occur.
Review and integration, journal of hydrology, 535, 235255. A modelling study of seawater intrusion in the liao dong bay coastal plain published in journal of marine science and technology china. These deltas contain fertile land suitable for intense agricultural development with associated. It is a natural process that can be made worse by human activities. Laboratory experiments and numerical simulations were conducted to investigate the influence of tidal oscillations on the behavior of the saltwater wedge. Documentation of the seawater intrusion swi2 package for. Modelling actual and future seawater intrusion in the. In times of drought, the freshwater body is conserved because the seaward flow is diminished. The spatial discrepancy of water resource distribution has caused the studies of seawater intrusion into. The increasing demand for fresh water in coastal regions is being met by the coastal aquifers. Pdf saltwater intrusion in coastal aquifers researchgate. Seawater intrusion into coastal aquifers in washington, 1978 by n. 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.
Pdf variations in groundwater density, resulting from variations in salinity, can have an important effect on groundwater flow. Coastal aquifers, seawat, climate change, sea level rise. Documentation of the seawater intrusion swi2 package for modflow by mark bakker, frans schaars, joseph d. Tidal influence on seawater intrusion in unconfined. Many queensland rivers have extensive deltas, which have large reserves of groundwater. Epa, 1990, andor to identify areas requiring additional research. In coastal regions, the quality of groundwater can be compromised due to saltwater intrusion swi caused by natural sea level rise slr and storm surge and anthropogenic pumping hazards. Techniques of waterresources investigations book 6, chapter a7, 77 p.
Assessment of saltwater intrusion along coastal areas of. Saltwater intrusion in coastal regions of north america. Seawater intrusion and salinization processes assesment in. As sea water intrusion progresses, existing pumping wells, especially those close to the coast, become saline and have to be abandoned. It shows an unconfined aquifer extending seaward and a watertable merging with the. Management of saltwater intrusion in coastal aquifers in. Tidal influence on seawater intrusion in unconfined coastal. Saltwater intrusion is the process by which saltwater infiltrates a coastal aquifer, leading to contamination of fresh groundwater. 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. Monitoring of seawater intrusion in coastal aquifers. Seawater intrusion associated with lowering of groundwater levels is an important issue in many of californias coastal groundwater basins. 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 in coastal aquifers concepts, methods. Seawater intrusion into coastal aquifers is a major problem in almost all parts of the world.
The spatial discrepancy of water resource distribution has caused the studies of seawater intrusion into china to. With time, seawater is introduced into the aquifer, reaching its wells and affecting water quality. Pdf seawater intrusion in coastal aquifers researchgate. Seawater intrusion and salinization processes assesment in a multistrata coastal aquifer in italy. Virtually all coastal aquifers around the world experience seawater intrusion to some degree due to the density differences between salt water. Seawater intrusion in coastal aquifers concepts, methods and. Seawater intrusion and coastal aquifer management in china. In this project, the focus is on salt water intrusion in coastal groundwater systems. Concepts, methods and practices ebook written by jacob bear, a.
Nile delta aquifer in egypt is one of these aquifers which subject to sever seawater intrusion from mediterranean sea. The induced gradients usually cause migration of salt water from the sea toward a. As a part of this effort, we have also investigated the impacts of various climatechange impacted variables such as average sea level and regional. Mar 20, 2014 seawater intrusion has been an important topic in hydrogeology in china in recent decades. 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. Seawater intrusion is the movement of ocean water into fresh groundwater, causing contamination of the groundwater by salt. Three dimensional simulation of seawater intrusion in a regional. Saltwater intrusion and climate change prince edward. Proceedings of the first international conference on saltwater intrusion and coastal aquifers monitoring, modeling and management, essaouira, morocco, april 2325, 2001. Different methods have been used to control swi in the coastal aquifers in.
Assessment of seawater intrusion potential from sealevel. A tecprobe temperature electrical conductivity is suitable for manual 1d. Numerical simulation of seawater intrusion in response to climate change impacts in north gaza coastal aquifer using seawat. 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. Mapping saline water intrusion into the coastal aquifer. Ecology, and social implications of coastal saltwater intrusion, bioscience. The numerical simulations of seawater intrusion indicate that one meter of sealevel rise would contribute an additional 10 to 15 meters of inland spread of the 1,000 mgl saline front and 20 to 30 meters of the 10,000 mgl saline front. Assessment of saltwater intrusion along coastal areas of nellore district, a. In many coastal aquifers, intrusion of seawater has become one of the major. Management of saltwater intrusion in coastal aquifers in queensland, australia j.
Seawater intrusion sgma usgs ca water science center. Most attention is concentrated on the marine water intrusion into aquifers. The effect of sealevel rise on seawater intrusion, therefore. This report on modelling of a coastal aquifer using feflow is a part of the research activities of ground water hydrology division of the institute. Analytical models of contaminant transport in coastal aquifers diogo t. In coastal regions, the groundwater as a primary or sole source of fresh water is. Saltwater intrusion has occurred to some degree in many of the coastal aquifers of the united states.
Groundwater from coastal aquifers is a better source for desalination than seawater. The simulation results presented in this paper are based on the densitydependent miscible. Download for offline reading, highlight, bookmark or take notes while you read seawater intrusion in coastal aquifers. May 25, 2008 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. Abstraction, desalination and recharge method to control. As sea water intrusion progresses, existing pumping wells, especially those close. Virtually all coastal aquifers around the world experience seawater intrusion to some degree due to the density differences between salt water and fresh.
The user has requested enhancement of the downloaded file. The development and management of fresh groundwater resources in coastal aquifers are seriously constrained by the presence of seawater intrusion. The goal of this research was to develop and test an approach for assessing the risk of swi in coastal aquifers. It also occurs when saltwater infiltrates freshwater aquifers and raises the groundwater table below. Plans are simple documents easy to access and to be used by communities. 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.
Seawater intrusion directly threatens the entral oasts economy, where many highvalue, saltsensitive crops, such as strawberries, are grown. Assessing the risk of saltwater intrusion in coastal aquifers. Dynamics of saltwater intrusion processes in saturated. Bear and others published seawater intrusion in coastal aquifers find, read and cite all the research you need on. The data obtained may help to pinpoint discrepancies between aquifer water quality and evectiveness of existing seawater control measures, in order to take appropriate management and legal steps u. 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. Seawater intrusion into coastal aquifers springerlink. Jul 31, 2007 seawater intrusion is the first cause of contamination of coastal aquifers date.
Consequently, seawater intrusion increases inland and wells become contamin ated. This report presents the hydrological aspects of salt water intrusion in coastal aquifers, salient features of saturatedunsaturated transport sutra model, and simulation of sea water intrusion. The purpose of this study is to simulate the seawater intrusion in a part of the coastal area in goa and. Saltwater intrusion can naturally occur in coastal aquifers, owing to the hydraulic connection between groundwater and seawater. A computer program for simulation of threedimensional variabledensity groundwater flow.
This tutorial shows the impact of intense groundwater exploitation of 50 wells in a simulation. Geological sciences 10 windinduced tides in ditches and canals ditch agricultural field agricultural field. Seawater intrusion is the first cause of contamination of coastal aquifers date. These developed methodologies are tested for an illustrative coastal aquifer study area. Geological sciences 9 subsidence and relative sealevel rise. Saltwater intrusion into the coastal aquifer has long been recognised as a major concern around the world. 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. Seawater intrusion processes, investigation and management vliz. Some of these impacts are already being felt today. 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. Lateral or horizontal intrusion occurs when excessive water withdrawals from an aquifer cause saline water from the coast to move inland vertical movement or upconing of saltwater can occur near a discharge.
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