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