Land Subsidence In Jakarta Research Articles

Current land subsidence in Jakarta: a multi-track SBAS InSAR analysis during 2017–2022 using C-band SAR data

In Jakarta, Indonesia, rapid urbanization and intensive groundwater extraction have led to significant land subsidence, posing challenges for sustainable urban management. This study utilized Interferometry Synthetic Aperture Radar (InSAR) integrated with multi-track data analysis to generate refined time-series and velocities of 2D displacement across Greater Jakarta. This study reveals notable variation in subsidence rates across different areas, with the most significant subsidence observed in Cikarang and the coastal regions of North Jakarta, which remains linear to this day. Notably, while the 2D approach improved accuracy by up to 53% at some locations, discrepancies at others indicated that simpler descending projections might sometimes yield better results. This underscores the necessity for a nuanced application of geodetic methods based on specific site conditions to effectively monitor and manage land subsidence in complex urban environments. Our findings highlight the critical importance of integrating multiple monitoring approaches to comprehensively address both vertical and horizontal displacement.

Changes in Extreme Rainfall in New Capital of Indonesia (IKN) Based on 20 Years of GPM-IMERG Data

The Indonesian government has decided to relocate the nation’s capital city from Jakarta on Java to the Nusantara Capital (IKN) on Kalimantan for political, socioeconomic, and infrastructure reasons, among others, including the threat of flood, earthquake, and land subsidence in Jakarta. However, IKN remains susceptible to hydro-meteorological disasters due to its equatorial location and high yearly rainfall amounts. In this article, we investigated changes in extreme rainfall in the IKN area over the last 20 years (2001- 2020) based on Integrated Multi-Satellite Retrievals for GPM (IMERG) version 6 data. Overall, extreme rain in the IKN area, especially in the Sepaku and Semboja sub-districts, has slightly declined in the last 2 decades, as shown by negative and positive Sen’s slopes of precipitation amount-based indices and the consecutive dry days (CDD), respectively. A decrease was also observed in RX1 day (annual maximum 1-day precipitation) and SDII (annual total rainfall divided by the number of wet days in the year) indices. This indicates that the IKN area is getting drier and could impact the availability of clean water in the future by increasing the intensity and duration of the drought. While the total amount of precipitation has decreased over the past 2 decades, there has been an increase in the intensity of more extreme precipitation events. This is evident from the rise in precipitation frequency-based indices (annual count of days with rainfall exceeding certain thresholds), such as R20mm and R50mm. The RX5day index (maximum 5-day precipitation) has also shown an increase. These changes increase the risk of flooding, so it is crucial to implement appropriate measures to mitigate the risk of floods in the IKN area. HIGHLIGHTS Extreme rain in the IKN area, especially in Sepaku and Semboja sub-districts, has slightly declined in the last 20 years. Increases were observed in the consecutive dry days (CDD) and some precipitation frequency-based indices. It is important to take appropriate measures to reduce the risk of floods and drought in the IKN areas. GRAPHICAL ABSTRACT

Politicising land subsidence in Jakarta: How land subsidence is the outcome of uneven sociospatial and socionatural processes of capitalist urbanization

Jakarta is sinking dramatically because of land subsidence, which in turn increases its vulnerability to tidal flooding. The explanation of land subsidence’s causes and the design of solutions is led by geoscientists and engineers, who tend to treat it as largely a technical problem. This paper takes issue with this. It sets out to contribute to politicizing land subsidence by analysing it as part of the sociospatial and socionatural transformations that characterize processes of urbanization. We propose an approach that allows showing how subsidence happens through urbanization’s interconnected moments of horizontal concentration, vertical extension, and differentiation – the weight of the built environment, the expansion of deep groundwater wells, and the remaking of the city (and beyond). By investigating the sociospatial correlation between land subsidence and the development of buildings, and the temporal correlation between land subsidence and the increase of groundwater wells we illustrate how land subsidence is intrinsic to (post-) New Order capitalism (1965–1998 and 1998-now). We also show that it proceeds in uneven ways: those who cause subsidence are not the ones who suffer most from it. Through a serious treatment of soil–water dynamics, our socionatural theorization also helps appreciate how urbanization is always co-shaped by interactions between human and non-human processes.

Land subsidence hazard in Indonesia: Present research and challenges ahead

Land subsidence has become a significant silent hazard in the big cities across Indonesia that aggravates future sustainable development. Land subsidence hazards hard-hit Java as the most densely populated island. This paper reviews Indonesia’s land subsidence hazards, particularly subsidence cases across the big cities on Java Island, Jakarta, Semarang, and Bandung. Generally, land subsidence research in Indonesia can be categorized into two broad focuses: monitoring subsidence rate and investigating land subsidence mechanism. This paper aims to present a comprehensive summary of the current status of land subsidence research in Indonesia and discusses the challenging issues encountered in research and mitigation measures. A qualitative literature review was used in this study for reviewed articles in the Google Scholar database published in Indonesian and English up to 2020. Land subsidence in Jakarta, Bandung, and Semarang is still ongoing at a high rate. Its mechanism is highly influenced by excessive groundwater withdrawal, although other natural and anthropogenic factors also play a part. This review proposes recommendations to alleviate the impacts of land subsidence hazards in Indonesia and for further research

Spatial information on the rate of subsidence in North Coastal Area of Java and the estimation of inundation in 2031

North Coastal Java Java is a fast-growing area because many big cities such as Jakarta, Cirebon, Pekalongan, Semarang, and Surabaya exist. This area is experiencing several environmental problems, the biggest of which is the problem of the rate of land subsidence. This problem is due to the geological structure. The Java Coast is located on soft soil, and some groundwater utilization activities are less controlled. This study aimed at (1) Obtaining information on the rate of land subsidence in 5 major cities on the northern coast of Java (Jakarta, Cirebon, Pekalongan, Semarang, and Surabaya) using remote sensing satellite data; (2) Analysing the accuracy of land subsidence using field survey data; (3) Estimating the potential of the region to be below 0 masl in 2031; and (4) Analysing the causes of land subsidence. The method used was Difference Interferometry Synthetic Aperture Radar (DInSAR) to determine the rate of land subsidence and simulate the rate of land subsidence in the future. The results showed that the rate of land subsidence in Jakarta (8/year), Cirebon (2 cm/year), Pekalongan (11.2 cm/year), Semarang (6 cm/year), and Surabaya (4.3 cm/year). The results of the research show that the error rate of the surface subsidence rate with validation results in the City of Jakarta is ± 0.01 m. with the value of Nash Sutcliffe Efficiency (NSE) =. 0.787 with a good category. Simulation results in 2031 from 3 big cities show that the area under 0 masl will increase by 2710 ha (Jakarta), 3565 ha (Pekalongan), and 846 ha (Semarang) from 2021. It seems that Pekalongan needs special attention to deal with the rate of land subsidence compared to other cities.

System Dynamic Simulation to Determine The Effect Of Water Consumption on Land Subsidence During Covid-19 Pandemic in Jakarta

Excessive groundwater extraction is believed to be one of the main factors for land subsidence which may be caused by tidal flooding due to the position of the surface which is lower than sea level. Covid-19 pandemic that has occurred in Indonesia since March 2020 has caused changes in water consumption patterns which derives from piped water and groundwater. There are many offices and industries that implement work from home (WFH) makes many buildings have a declining occupancy rate. With the decrease in the occupancy rate of the WFH policy, there will be a possibility that groundwater consumption from high-rise buildings that draw groundwater from deep aquifers can be reduced. This research is in the form of modelling and simulation that is used to build a level of understanding on a whole system as well as the interrelationships and interactions between its constituent variables. The purpose of this research was to determine the effect of groundwater consumption during Covid-19 pandemic on land subsidence in Jakarta using the dynamic system simulation method. The results showed that the work from home policy reduces groundwater consumption by 64.7%. In addition, the reduction in groundwater consumption during the Covid-19 pandemic caused land subsidence in Jakarta slows down and the rate of land subsidence in Jakarta decreased from 3.7 cm/year to 1 cm/year.

Nature-based solutions for integrating flood and land subsidence: A case study in Jakarta and Semarang

Floods in Jakarta and Semarang are more frequent and impact more expansive areas. So far, flood management has been done mainly by increasing the capacity of drainage channels and draining water into the sea more quickly. This flood management needs to be evaluated because it leads land subsidence in Jakarta and Semarang to deepen. Thus, this research aims to identify the extent to which land subsidence causes the expansion of floods and alternative solutions to deal with floods and land subsidence in an integrative manner, especially in Ciliwung (Jakarta) and Garang (Semarang) watersheds. The method used was a review of various publications concerning findings of land subsidence, flooding, and the experiences of several countries in dealing with these problems. The results showed that land subsidence has occurred in Jakarta and Semarang. As a result of land subsidence, the flooding areas have increased due to the increase in lowlands, and therefore, it is difficult for the existing water to flow into the sea. Handling floods and land subsidence cannot be conducted locally but must be carried out in an integrative manner with a watershed and groundwater basin approach. One of the causes of land subsidence is excessive groundwater extraction. On the other hand, the groundwater must be increased. The increase in groundwater supplies not only reduces land subsidence but also reduces flooding, seawater intrusion and prevents drought in the dry season. A nature-based solution for reducing flood and land subsidence can be achieved by increasing vegetation cover and constructing water conservation buildings in the upstream areas.

Land subsidence in Jakarta and Semarang Bay – The relationship between physical processes, risk perception, and household adaptation

Sea level rise (SLR) is among the most pressing challenges for urban coastal areas. While geocentric (eustatic) SLR receives widespread attention in politics and media, relative SLR at the coast, mainly caused by land subsidence, is still comparatively under-researched despite much higher rates. This paper introduces a combined natural and social science study to bring subsidence more to the forefront of coastal hazard research. We use data from radar altimetry, GNSS controlled tide gauge stations, and InSAR mapping to characterize regional and relative SLR at Jakarta and Semarang Bay, and focus-group discussions and a standardized household survey to analyze risk perceptions and adaptation.Our analysis of InSAR, radar altimetry, and corrected tide gauges clearly identifies subsidence as the major coastal threat in our study areas. The InSAR analysis for Semarang shows stable trends of subsidence up to ~100 mm/a. For Jakarta, our analysis reveals more complex spatial and temporal patterns with rates around 60 mm/a; revealing significant changes to previous studies. Our analysis of radar altimetry data since 1993 shows a moderate regional SLR of 2.1 mm/a off Semarang and 3.2 mm/a off Jakarta.The InSAR data are integrated into our statistical analysis of household responses towards subsidence. We found, that in contrast to fast-onset events, constantly proceeding subsidence becomes normalized in peoples’ perceptions and responses are integrated into day-to-day habits. Thus, risk perception is a far lesser determinant of responses towards subsidence than it is for fast-onset events. Hence, our results relativize former assumptions that risk perception and not actual exposure lead to action. Moreover, we found that local people are not willing to vacate highly exposed areas. Their views need to be included in municipal disaster risk reduction, the urgency of which clearly lies on mitigating subsidence effects rather than on building protection against regionally rising sea levels.

A Review Disaster Mitigation of Jakarta Land Subsidence Areas

The Jakarta Capital Special Region of Jakarta is an area in the Java Island that has the highest level of vulnerability to land subsidence disasters. Land subsidence is caused by several factors such as excessive use of groundwater and natural compression of soil conditions. This study used a review analysis method based on a literature study on mitigation of land subsidence disasters in Jakarta city. The mitigation planning of land subsidence disasters in Jakarta will refer to government regulations on disaster management and Jakarta City spatial planning. Disaster mitigation is necessary to anticipate or reduce disaster risk. Disaster mitigation is a series of efforts to reduce disaster risk through physical development combined with awareness and capacity building in dealing with disaster threats. Education cannot be separated from the active role of the community and local government. High-densely populated areas will lead to more use of groundwater in Jakarta city. The excessive use of groundwater has resulted in more intensive land subsidence in Jakarta’s urban area. The safe zone mapping of subsidence disasters is prominent to reduce and control land subsidence disasters. The government’s efforts to lessen the impacts of land subsidence are by educating the population in disaster areas.

Land Subsidence Susceptibility Mapping in Jakarta Using Functional and Meta-Ensemble Machine Learning Algorithm Based on Time-Series InSAR Data

Areas at risk of land subsidence in Jakarta can be identified using a land subsidence susceptibility map. This study evaluates the quality of a susceptibility map made using functional (logistic regression and multilayer perceptron) and meta-ensemble (AdaBoost and LogitBoost) machine learning algorithms based on a land subsidence inventory map generated using the Sentinel-1 synthetic aperture radar (SAR) dataset from 2017 to 2020. The land subsidence locations were assessed using the time-series interferometry synthetic aperture radar (InSAR) method based on the Stanford Method for Persistent Scatterers (StaMPS) algorithm. The mean vertical deformation maps from ascending and descending tracks were compared and showed a good correlation between displacement patterns. Persistent scatterer points with mean vertical deformation value were randomly divided into two datasets: 50% for training the susceptibility model and 50% for validating the model in terms of accuracy and reliability. Additionally, 14 land subsidence conditioning factors correlated with subsidence occurrence were used to generate land subsidence susceptibility maps from the four algorithms. The receiver operating characteristic (ROC) curve analysis showed that the AdaBoost algorithm has higher subsidence susceptibility prediction accuracy (81.1%) than the multilayer perceptron (80%), logistic regression (79.4%), and LogitBoost (79.1%) algorithms. The land subsidence susceptibility map can be used to mitigate disasters caused by land subsidence in Jakarta, and our method can be applied to other study areas.

Land subsidence rate analysis of Jakarta Metropolitan Region based on D-InSAR processing of Sentinel data C-Band frequency

Land subsidence in Jakarta has been reported by many studies using various geodetic techniques. High exploitation of groundwater is the main factor of increasing land subsidence rate in Jakarta. The impact of land subsidence can be seen in several forms such as the damage on buildings and infrastuctures and the change of surface water pattern flow. This paper presents the update status and analysis of land subsidence of Jakarta Metropolitan Region (Jabodetabek) based on Differential Interferometric Synthetic Aperture Radar (D-InSAR) technique. D-InSAR technique based on interferogram that developed from a coherence technology of active radar imaging. Two images acquired with the same nominal geometry is required to develop interferometry SAR by using phase as a fraction of the wave, and change to distance. The displacement map is the final result of interferometry SAR and external Digital Elevation Model (DEM) required to remove topographic phase. Displacement map using pair of Sentinel data that acquired on March 18, 2017 and March 13, 2018 was successfully developed. The highest rate of land subsidence with 6 cm/year occurred in eastern part and western part of north area of Jakarta, some part in West Jakarta, Central Jakarta, and South Jakarta. The similar rate also occurred in Bekasi City, Bekasi Regency, Depok City, and Tangerang Regency. The moderate rate of land subsidence occurred in Tangerang City and South Tangerang City with 2-3 cm/year. Jakarta Metropolitan Region is a susceptible area of flooding. In this study, land subsidence has a similar pattern with the emergence of flood inundation. Therefore, the increasing of areas with flood inundation is affected by land subsidence. Monitoring of land subsidence rate in Jakarta Metropolitan Region by using D-InSAR Sentinel data is highly required due to high temporal resolution and accurate data especially for flood management and other urban development management, and free access of the data.

The investigation on high-rise building tilting from the issue of land subsidence in Jakarta City

One of the issues from land subsidence consequences is tilting on building. At the places where differential subsidence is existed we might literally see the building tilted. Jakarta is a mega city in Indonesia where significant land subsidence (e.g. 1-26 centimeter per year) is happening today. Issue of tilting on buildings due to land subsidence in Jakarta has been raisin. There is one high-rise building namely Menara Saidah which is judging to be tilting. As consequences the building has been abandoned. The building in the office of House of Representative is also being rumored to be tilting. Judging and rumored are not scientific, we need real measurements. There are more than two hundreds of high-rise buildings established in Jakarta city. We use the Terrestrial Laser Scanner survey to investigate the issue of high-rise building. This technology has capability to create 3D object with milimeter accuracy. Tilting on the building can be seen simply by their verticality. We have chosen several high-rise buildings to accurately measure, especially where large subsidence is there. This paper is a highlight on the investigation. As the conclusion we found the verticality of investigated buildings are still within the tolerance.

Insight look the subsidence impact to infrastructures in Jakarta and Semarang area; Key for adaptation and mitigation

Land subsidence is not a new phenomenon for Jakarta and Semarang areas. According to some publications, the value of Jakarta’s subsidence may reach 2-4 meter in certain place. Meanwhile, more than 2 meter of subsidence is taking place in northern part of Semarang. Some techniques are being used to derive land subsidence information in these areas such as repeated leveling measurements, GPS surveys, and InSAR measurements. The impact of land subsidence in Jakarta and Semarang could be seen in several ways, such as sea inundation (“Rob” in Javanese), problem on infrastructures, the wider expansion of flooding areas, etc. Cracking on housing, street, “sinking” on the bridges and dyke, problems on drainage are examples of infrastructures problems due to the land subsidence. Huge costs have already been spent to fixing those infrastructures problems both in Jakarta and Semarang. Since mostly liniear pattern of land subsidence are recognized in both area today and probably in the next years to come, in this case the impact especially on infrastructures are probably will getting worse. Insight look the subsidence impact to the infrastuctures in Jakarta and Semarang area would raisen the concern, and become key for adaptation and mitigation.

Mapping of Land Subsidence Induced by Groundwater Extraction in Urban Areas as Basic Data for Sustainability Countermeasures

Estimation of land subsidence induced by groundwater extraction has been observed by some researchers using field instrumentation as well as a spatial mapping technique. Among six Asian cities previously studied (Bangkok, Jakarta, Manila, Osaka, Seoul, Taipei, and Tokyo), the rate of land subsidence in Jakarta is the highest in the period from 1900–2010. In order to improve the applicable monitoring system and obtain comprehensive results for subsidence measurement, tools for raising the government’s and society’s awareness of subsidence are needed. This paper aimed to determine a benchmark and perform an analysis of sustainable counter measures for land subsidence induced by groundwater extraction in the urban areas of Jakarta city, using a continuous monitoring system and integrated data management system. Land subsidence was measured using field monitoring techniques, such as an extensometer, a leveling survey (global positioning system,GPS; geodetic measurements), and observation wells; this was conducted in some locations in north Jakarta from 1990–2016. The results from the visual observation identified an average land subsidence rate of 1.65 cm/year, while the GPS geodetic measurements ranged from 0–12 cm/year. Monitoring from seven extensometer sensors installed in different borehole elevations revealed subsidence of 0.66 cm on average. Meanwhile, the groundwater surface level ranged from 0.6 m to 44 m from the surface, with the deepest being in the area of Bintaro, South Tangerang. Data analysis was conducted using a computer simulation to investigate the inter-connection between land subsidence and groundwater extraction. Consequently, land subsidence was found to have a strong association with groundwater extraction. Integrated data management systems, including data sharing, are needed to improve the appropriate monitoring system of land subsidence in Jakarta.

Study on the risk and impacts of land subsidence in Jakarta

Abstract. Jakarta is the capital city of Indonesia located in the west-northern coast of Java island, within a deltaic plain and passes by 13 natural and artificial rivers. This megapolitan has a population of about 10.2 million people inhabiting an area of about 660 km2, with relatively rapid urban development. It has been reported for many years that several places in Jakarta are subsiding at different rates. The main causative factors of land subsidence in Jakarta are most probably excessive groundwater extraction, load of constructions (i.e., settlement of high compressibility soil), and natural consolidation of alluvial soil. Land subsidence in Jakarta has been studied using leveling surveys, GPS surveys, InSAR and Geometric-Historic techniques. The results obtained from leveling surveys, GPS surveys and InSAR technique over the period between 1974 and 2010 show that land subsidence in Jakarta has spatial and temporal variations with typical rates of about 3–10 cm year−1. Rapid urban development, relatively young alluvium soil, and relatively weak mitigation and adapatation initiatives, are risk increasing factors of land subsidence in Jakarta. The subsidence impacts can be seen already in the field in forms of cracking and damage of housing, buildings and infrastructure; wider expansion of (riverine and coastal) flooding areas, malfunction of drainage system, changes in river canal and drain flow systems and increased inland sea water intrusion. These impacts can be categorized into infrastructural, environmental, economic and social impacts. The risk and impacts of land subsidence in Jakarta and their related aspects are discussed in this paper.

On correlation between urban development, land subsidence and flooding phenomena in Jakarta

Abstract. Jakarta is the capital city of Indonesia with a population of about 10.2 million people, inhabiting an area of about 660 square-km. It is located within a deltaic plain and passes by 13 natural and artificial rivers. In the last three decades, urban development of Jakarta has grown very rapidly in the sectors of industry, trade, transportation, real estate and many others, which has caused several negative environmental impacts. In turns Jakarta is then prone toward a few natural hazards mainly land subsidence and flooding. In general, based on geodetic measurement methods (e.g. Leveling, GPS surveys, and InSAR), conducted since 1982 up to 2014, it is obtained that land subsidence in Jakarta exhibits spatial and temporal variations, with the typical rates of about 3 to 10 cm year−1. In general, the impacts of land subsidence in Jakarta can be seen in the forms of cracking of permanent constructions and roads, changes in river canal and drain flow systems, wider expansion of coastal and/or inland flooding areas, and malfunction of drainage system. Several areas along the coast of Jakarta already have experienced tidal flooding during high tide periods. These coastal flooding usually occurs in the areas with relatively large subsidence rates. Subsidence in the areas along the rivers which are flowing throughout Jakarta will also worsen the impacts of riverine flooding. The changes in river canal and drain flow systems and malfunction of drainage system due to land subsidence will also aggravate the flooding. Land subsidence will have direct and indirect affects with the flooding in Jakarta, both in coastal or inland areas.

TERRASAR-X DINSAR FOR LAND DEFORMATION DETECTION IN JAKARTA URBAN AREA, INDONESIA

The X-band synthetic aperture radar (SAR) onboard the TerraSAR-X satellite is useful for land subsidence detection and monitoring, since the sensor provides high spatial resolution data with a relatively short repetition cycle of 11 days. Jakarta is one of the largest cities in the world with population more 10 million as of 2011. The area has been suffering from significant effects of land subsidence that causes damages to public facilities, buildings, and other public and private properties. In this work, we exploit the capability of TerraSAR-X for detecting land subsidence in Jakarta during a four year period between 2010 and 2013 using differential interferometry SAR (DInSAR) technique. Our analysis reveals that two northern areas in the city exhibit clear indications of land subsidence varying from 8.5 to 17.5 cm/year, mostly caused by intensive human activities in addition to the vulnerability due to geological structures of these areas.

TERRASAR-X DINSAR FOR LAND DEFORMATION DETECTION IN JAKARTA URBAN AREA, INDONESIA

The X-band synthetic aperture radar (SAR) onboard the TerraSAR-X satellite is useful for land subsidence detection and monitoring, since the sensor provides high spatial resolution data with a relatively short repetition cycle of 11 days. Jakarta is one of the largest cities in the world with population more 10 million as of 2011. The area has been suffering from significant effects of land subsidence that causes damages to public facilities, buildings, and other public and private properties. In this work, we exploit the capability of TerraSAR-X for detecting land subsidence in Jakarta during a four year period between 2010 and 2013 using differential interferometry SAR (DInSAR) technique. Our analysis reveals that two northern areas in the city exhibit clear indications of land subsidence varying from 8.5 to 17.5 cm/year, mostly caused by intensive human activities in addition to the vulnerability due to geological structures of these areas.

Mapping land subsidence in Jakarta, Indonesia using persistent scatterer interferometry (PSI) technique with ALOS PALSAR

Jakarta is the capital of Indonesia. It is one of the largest cities with an around 10 million population as for 2010, covering an area of about 661 square kilometers. The land subsidence phenomena in several areas of Jakarta are well known for many years. Land subsidence does damage infrastructures in the city; therefore, it has to be closely monitored and analysed. In this paper, the authors have demonstrated the capability of the PALSAR sensor aboard the Japanese ALOS satellite for large-scale mapping of land subsidence in Jakarta. Mapping results were produced from 17 ALOS PALSAR L-band radar images using persistent scatterer radar interferometry (PSI). The GEOS-PSI software, developed by the Geodesy and Earth Observing Systems group at UNSW for PSI analysis, was used to detect and map those land subsidence. The results showed that the land in the area of Jakarta was deforming at different rates across several zones. The land subsidence measured from ALOS PALSAR imagery were cross-examined with the subsidence values obtained from 4 GPS campaign surveys by the authors at 19 stations between 2007 and 2010. The magnitudes and trends of the deformation obtained from both techniques agreed well in general for those pinpoints of GPS. After the removal of 2 suspected outliers in GPS measurements, the subsidence rate difference between the two techniques range from −29 to 6mm/year, with a standard deviation of 9mm/year and an average absolute difference of 8mm/year. This research has suggested that PSI with L-band ALOS PALSAR data can be a promising technique to complement the GPS surveying for monitoring land subsidence in super large cities like Jakarta.

Land subsidence of Jakarta (Indonesia) and its relation with urban development

Jakarta is the capital city of Indonesia with a population of about 9.6 million people, inhabiting an area of about 660 square-km. In the last three decades, urban development of Jakarta has grown very rapidly in the sectors of industry, trade, transportation, real estate, and many others. This exponentially increased urban development introduces several environmental problems. Land subsidence is one of them. The resulted land subsidence will also then affect the urban development plan and process. It has been reported for many years that several places in Jakarta are subsiding at different rates. The leveling surveys, GPS survey methods, and InSAR measurements have been used to study land subsidence in Jakarta, over the period of 1982–2010. In general, it was found that the land subsidence exhibits spatial and temporal variations, with the rates of about 1–15 cm/year. A few locations can have the subsidence rates up to about 20–28 cm/year. There are four different types of land subsidence that can be expected to occur in the Jakarta basin, namely: subsidence due to groundwater extraction, subsidence induced by the load of constructions (i.e., settlement of high compressibility soil), subsidence caused by natural consolidation of alluvial soil, and tectonic subsidence. It was found that the spatial and temporal variations of land subsidence depend on the corresponding variations of groundwater extraction, coupled with the characteristics of sedimentary layers and building loads above it. In general, there is strong relation between land subsidence and urban development activities in Jakarta.