Prediction Of Seawater Intrusion Research Articles

Assessment of groundwater salinization impact in coastal aquifers based on the shared socioeconomic pathways: An integrated modeling approach

Seawater intrusion (SWI) has become a significant threat to human health and sustainable economic development in coastal areas with the rapid pace of climate change. Therefore, it is crucial to determine the response of SWI to climate change. However, most studies cannot reflect the direct impact of future climate change on groundwater salinity. This study first established the SWAT-MODFLOW coupled model after unifying both spatiotemporal computational units. Streamflow, groundwater level observation data, etc., were used to calibrate and validate the coupled model. And then SEAWAT model was loaded into the coupled model to form a new integrated model. Finally, precipitation of six Global Climate Models (GCMs) under two shared socioeconomic pathways (1–2.6 and 5–8.5 scenarios) was imported into the above calibrated integrated model separately to make SWI prediction from December 30, 2020, to December 30, 2030. The results show that this integrated model accurately reflected the study area's current flow and concentration field distribution. Precipitation under different ssps had little effect on future SWI, while the uncertainty of SWI prediction was mainly derived from different GCMs. This study provides important implications for exploring the occurrence and the prediction of SWI in the coastal aquifer. It has specific reference significance for the optimal management of water resources in coastal areas and the effective mitigation of SWI.

Relationship between Time Lapse Microgravity Anomaly with Na and Cl Content for prediction of Sea Water Intrusion in Tourism Area Kota Lama Semarang Indonesia

This research is motivated by changes in infrastructure that occur in the old city, the changes in question are the frequent occurrence of flooding in this region. The flooding that occurred was estimated to be caused by subsidence. In addition, subsidence that has other effects, for example seawater intrusion in the Old City, which is located close to the north coast of Java, is also relatively close to about 3 km. The purpose of this study was to find a relationship between seawater intrusion and micro-gravity anomalies between times. The methods carried out are as follows: (1) choose Gravimeter with micro precision. For this study using the Autograv CG5 type, (2) determining the location of the measurement point, which is not expected to experience physical damage due to natural or human behavior for a certain interval, (3) measuring gravity for two different periods in September 2017 and March 2018 at the same point, (4) processing data with initial corrections, namely tidal correction to reduce tidal effects, float correction, and correction of the dynamics of groundwater levels associated with rainfall, and (5) conduct chemical tests of water samples taken from residents’ wells at the Research site. The results showed that the negative time-weight gravity anomaly correlated with an average groundwater level decrease of 15,468 cm. This is in accordance with the fact that during this range rainfall trends tend to decline from September 2017 to March 2018. This decrease in ground water causes maximum subsidence and occurs in the south-southwest 2.3 cm. This zone experiences sea water intrusion which is characterized by the content of Na (60-100%) and Cl (100-160%).

Numerical investigation on seawater intrusion and water leakage in different types of stratified coastal aquifers

Prediction of seawater intrusion (SWI) will increase the proper planning for withdrawal of groundwater, and it will help the freshwater management in the future. Since heterogeneous aquifers are more widespread than homogeneous one, this study aims to use the density-dependent SEAWAT code to investigate the influence of different combinations of hydraulic conductivity (K) on SWI. The effects of numbers and arrangement of layers with different K are examined on (a) toe position, (b) freshwater–seawater mixing zone thickness (Wt) and (c) leakage from adjacent layers in a steady-state condition. For this purpose, numerous scenarios with different K were simulated and analyzed. The results of horizontally layered aquifers showed that the streamlines are broken on boundary of layers. It was observed that when K is decreased, especially at the middle layer, the refraction angle is increased and consequently Wt is increased. The Wt in vertically layered cases was less than horizontally layered aquifers because of less streamline breakage. Also, random arrangement of K directs the saline flow to higher permeability zones. Thus, the SWI extent in this type of aquifer was more tangible than other types. Because of the difference in hydraulic head at layer borders, the seepage rate significantly increases nearby toe position and the dominant direction is upward. However, in the steady-state condition, the type of flow did not differ significantly for boundary cells of layers at the vicinity of toe position.

CORRELATION ANALYSIS BETWEEN SEAWATER INTRUSION AND MANGROVE GREENBELT

Seawater intrusion is an entry process of seawater to land. Many factors have caused seawater intrusion from freshwater exploitation until mangrove degradation. Mangrove ecosystem is a type of forest ecosystem which has an ability to reduce seawater intrusion. This paper analyzes the estimation and prediction of seawater intrusion and correlation between widths of mangrove with seawater intrusion. The relation analysis between the width of mangrove greenbelt with seawater intrusion used an equation model to predict seawater intrusion. The research method used sampling technique, system analysis with powersim software, correlation analysis and mathematical method with trend line analysis. Results show that (1) the mangrove density in the coastal area is approximately 50 – 109 trees/ha. (2) Simulation results showed seawater intrusion rate was about 0.20 km year (with mangrove as a component system), but reached 0.3 – 0.4 km/year (without mangrove as a component system). (3) The simulation result also showed that freshwater salinity was estimated to increase from 1.92 ppt to 4.86 ppt. (4) The relation model between seawater intrusion and mangrove greenbelt showed that correlation coefficient was 0.97 with the equation seawater intrusion (m) = 2264.9 * exp (-0.009 * the width of mangrove greenbelt (m)), the correlation of mangrove width with seawater intrusion was 0.97. (5) Avicennia marina , Avicennia alba , Rhizophora styllosa , Sonneratia alba and Sonneratia caseolaris were the mangrove species that had the best ability to reduce seawater intrusion.

CORRELATION ANALYSIS BETWEEN SEAWATER INTRUSION AND MANGROVE GREENBELT

Seawater intrusion is an entry process of seawater to land. Many factors have caused seawater intrusion from freshwater exploitation until mangrove degradation. Mangrove ecosystem is a type of forest ecosystem which has an ability to reduce seawater intrusion. This paper analyzes the estimation and prediction of seawater intrusion and correlation between widths of mangrove with seawater intrusion. The relation analysis between the width of mangrove greenbelt with seawater intrusion used an equation model to predict seawater intrusion. The research method used sampling technique, system analysis with powersim software, correlation analysis and mathematical method with trend line analysis. Results show that (1) the mangrove density in the coastal area is approximately 50 – 109 trees/ha. (2) Simulation results showed seawater intrusion rate was about 0.20 km year (with mangrove as a component system), but reached 0.3 – 0.4 km/year (without mangrove as a component system). (3) The simulation result also showed that freshwater salinity was estimated to increase from 1.92 ppt to 4.86 ppt. (4) The relation model between seawater intrusion and mangrove greenbelt showed that correlation coefficient was 0.97 with the equation seawater intrusion (m) = 2264.9 * exp (-0.009 * the width of mangrove greenbelt (m)), the correlation of mangrove width with seawater intrusion was 0.97. (5) Avicennia marina, Avicennia alba, Rhizophora styllosa, Sonneratia alba and Sonneratia caseolaris were the mangrove species that had the best ability to reduce seawater intrusion.

KAJIAN DAERAH TERINTRUSI AIR LAUT DI WILAYAH PESISIR KECAMATAN KUTA UTARA, KABUPATEN BADUNG

The total population of District Kuta Utara 2014 recorded 68.422 people with an average population density of 2,021 people/km2 while the number of tourism accommodation facilities (hotels, villas, restaurants) recorded 399 pieces. The rapid of population growth and the development of tourism accommodation facilities require ground water more increasing. Intake of large amounts of ground water potential to cause pollution/ sea water intrusion. This study aims to determine the quality of the groundwater, knowing distribution maps sea water intrusion and to predict the level of sea water intrusion coming years. This research method uses descriptive quantitative method. Furthermore, to determine the quantity and quality of ground water was measured groundwater levels and analysis of the parameters of temperature, total dissolved solid, pH, chloride, hardness and electrical conductivity of the 60 sample wells. Results of analysis of each of the key parameters that can be mapped and known overlay distribution maps sea water intruded area. The observation of the quantity and quality of groundwater in coastal areas of Kuta Utara subdistrict shows the range of the depth of the ground water level between -5.15 meters to -22.16 meters. Results of the analysis of ground water quality of the 60 groundwater samples showed that there has been a decline in the quality of ground water is as much as 14 samples total dissolved solid (TDS) the highest reaches 1,122 mg/ l, the highest electrical conductivity reached 1,677 ìMhos / cm and the highest chloride reached 532, 5 mg/l. Distribution maps sea water intruded area shows that in coastal areas troubled district of Kuta Utara indicated seawater intrusion, especially in the area of Petitenget and Batubelig, Kerobokan Kelod Village area of 78.44 Ha. Prediction of sea water intrusion in 2022 was highest in the area of tourism accommodation caused by ground water extraction enough much, kind of gray-brown soil regosol has a rough texture and high permeability characteristics so it is easy to pass groundwater.

Prediction of sea water intrusion for mining activity in close precincts of sea shore

The mining lease area of Surka [District Bhavnagar, Gujarat (India)] is located within 6–12 km horizontal distance of sea shore of Gulf of Cambay. Whenever, there will be onset of lignite extraction, there will be always a threat of sea water intrusion into the mining lease area due to its close proximity to seashore. This article describes the prediction of sea water intrusion into the lease area of whole mining block using Ghyben-Herzberg relation between fresh and saline water, Remote Sensing, Ground Truth verification, Electrical Resistivity Survey and groundwater table monitored during the year 2004. As per the Ghyben-Herzberg relation, results show that there will not be sea water intrusion. If there is excess pumping of water then also the basement rock below the lignite seam will put hindrance to any possible upconing of saline water interface.

Finite element simulation of a saltwater/freshwater interface with indirect toe tracking

The porous media two‐layer flow problem involving fluids of different density separated by an immiscible interface is solved using the Galerkin finite element method in one dimension. Each layer is present only over a portion of the domain. The transition from two layers to one constitutes a moving boundary which must be calculated as part of the solution. An indirect numerical procedure using a fixed grid is proposed to track the boundary. The procedure uses the Gaussian quadrature points, a nonlinear variation of layer saturation across those elements containing a moving boundary and an imaginary ‘extra thickness’ of the absent layer. It is illustrated with an application to the gravity segregation problem. In this example the model performs as accurately as and is considerably less expensive than equivalent grid regeneration or moving grid schemes. The primary area of application is to the prediction of sea water intrusion in groundwater aquifers using regional, essentially horizontal flow models.