GIS-Based Study of Land Subsidence in the City of Bologna

In this study, we monitor pavement and land subsidence in Tabriz city in NW Iran using X-band synthetic aperture radar (SAR) sensor of Cosmo-SkyMed (CSK) satellites (2017–2018). Fifteen CSK images with a revisit interval of ~30 days have been used. Because of traffic jams, usually cars on streets do not allow pure backscattering measurements of pavements. Thus, the major paved areas (e.g., streets, etc.) of the city are extracted from a minimum-based stacking model of high resolution (HR) SAR images. The technique can be used profitably to reduce the negative impacts of the presence of traffic jams and estimate the possible quality of pavement in the HR SAR images in which the results can be compared by in-situ road roughness measurements. In addition, a time series small baseline subset (SBAS) interferometric SAR (InSAR) analysis is applied for the acquired HR CSK images. The SBAS InSAR results show land subsidence in some parts of the city. The mean rate of line-of-sight (LOS) subsidence is 20 mm/year in district two of the city, which was confirmed by field surveying and mean vertical velocity of Sentinel-1 dataset. The SBAS InSAR results also show that 1.4 km2 of buildings and 65 km of pavement are at an immediate risk of land subsidence.

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Subsidence and Flooding in Bangkok

The Physical Geography of Southeast Asia ◽

10.1093/oso/9780199248025.003.0033 ◽

2005 ◽

Author(s):

Noppadol Phienwej ◽

Prinya Nutalaya

Keyword(s):

Land Subsidence ◽

Flood Risk ◽

Land Surface ◽

Road Construction ◽

Central Plains ◽

Central Plain ◽

The North ◽

Chao Phraya River ◽

The 1960S ◽

The City

Bangkok, the capital of Thailand, is situated on flat, low land in the southern part of the Central Plain, one of the main physical units of the country. Through the heart of the city, the Chao Phraya flows from the north and discharges into the Gulf of Thailand, 25 km south of the city centre. The city was founded in 1782, and in its early years numerous klongs (canals) were dug for transportation and defence uses. These canals became corridors of early development, and banks were lined with houses, shop-houses, and temples, etc. With the beauty of its waterway landscape, Bangkok was once dubbed the Venice of the East. Unfortunately, such a resemblance no longer exists as most of the canals have been backfilled to make room for road construction in recent urbanization. The Bangkok metropolis, which at present has a population in excess of 10 million, has expanded rapidly on both banks of the river since 1950. It has encroached into surrounding provinces, covering an area of approximately 60 × 70 km. Owing to its flat topography and close proximity to the sea, flooding threatens the city annually. Modern urbanization has resulted in the drastic destruction or blockage of natural drainage paths, increasing the flood risk to the city. Severe land subsidence from excessive groundwater extraction since the 1960s has intensified the flood risk, as well as creating numerous foundation problems. At present the land surface in some areas is already below mean sea level. The city now has to rely on a flood protection system to prevent inundation. However, its effectiveness is only temporary because land subsidence has not yet ceased. The Central Plain is formed by the Chao Phraya River, the largest in the country. The river basin stretches from the Northern Highland to the Central Plain and covers about one-third of the country (514 000 km2). The Central Plain can be divided into the Upper and Lower Central Plains. The former extends from Tak to Nakhon Sawan Provinces. Four main rivers, namely, the Ping, the Wang, the Yom, and the Nan, which originate in the Northern Highland, traverse the plain and join together at Nakhon Sawan, 240 km north of Bangkok, to form the Chao Phraya River.

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Detection of silent subsidence over extensive area by SBAS DInSAR: a case study of Southern Bali, Indonesia

E3S Web of Conferences ◽

10.1051/e3sconf/202015302003 ◽

2020 ◽

Vol 153 ◽

pp. 02003

Author(s):

Putu Edi Yastika ◽

Norikazu Shimizu ◽

Ni Nyoman Pujianiki ◽

I Gede Rai Maya Temaja ◽

I Nyoman Gede Antara ◽

...

Keyword(s):

Land Subsidence ◽

Groundwater Extraction ◽

Severe Damage ◽

Human Needs ◽

Points Of Interest ◽

Linear Behavior ◽

The World ◽

Spatio Temporal ◽

The City

Numerous cities around the world are facing the problem of land subsidence. In many cases, it is the excessive groundwater extraction to meet human needs that leads to this subsidence. Since land subsidence rates are very slow (a few centimeters per year), the subsidence usually remains unnoticed until it has progressed to the point of causing severe damage to buildings, houses, and/or other infrastructures. Therefore, it is very important to detect the presence of subsidence in advance. In this study, screening for the presence of land subsidence in the city of Denpasar, Bali, Indonesia is conducted. The Sentinel-1A/B SAR dataset, taken from October 2014 to June 2019, is processed using the SBAS DInSAR method. Subsidence is found in the districts of Denpasar Selatan, Denpasar Barat, and Kuta, which falls in the range of -100 mm to -200 mm in an area of about 93.03 ha. All the extracted points of interest show the subsidence having linear behavior. The spatio-temporal behavior of the subsidence in Denpasar is presented clearly. However, the mechanism and the deriving factors of the subsidence remain unclear. Therefore, further studies are needed.

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The effect of land subsidence on the selection of raw water sources in hotel and apartment buildings in Semarang city

IOP Conference Series Earth and Environmental Science ◽

10.1088/1755-1315/896/1/012033 ◽

2021 ◽

Vol 896 (1) ◽

pp. 012033

Author(s):

B Syahputra ◽

B F T Kiono ◽

Sudarno

Keyword(s):

Land Subsidence ◽

Water Sources ◽

City Government ◽

Raw Water ◽

Apartment Buildings ◽

Deep Wells ◽

Level Ii ◽

Expert Team ◽

The City ◽

Selection Of

Abstract The Semarang City Government prohibits groundwater/deep wells in hotel and apartment buildings because the use of groundwater or deep wells in locations that have experienced subsidence will further aggravate the subsidence. The method used in this research is to purposively select hotel and apartment buildings in Semarang that have received an assessment by the Semarang City Building Expert Team and have received a certificate of serviceability. Furthermore, compare the map of land subsidence in some areas of the city of Semarang with the natural water sources used by the hotel and apartment buildings. The research results showed that from 10 hotel and apartment buildings, there were 7 that used deep wells in zone level II, namely subsidence between 2.1 to 4 cm/year. Meanwhile, 3 other hotel and apartment buildings use water from the Municipal Drinking Water Company of Semarang. The existence of hotel and apartment buildings that use groundwater/deep wells in zone level II will increase and trigger the more significant subsidence in the area, thereby increasing the level of subsidence to level III.

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

Journal of Urban and Environmental Engineering ◽

10.4090/juee.2013.v7n2.195205 ◽

2013 ◽

pp. 195-205 ◽

Cited By ~ 5

Author(s):

Ratih Fitria Putri ◽

Luhur Bayuaji ◽

Josaphat Tetuko Sri Sumantyo ◽

Hiroaki Kuze

Keyword(s):

Land Subsidence ◽

High Spatial Resolution ◽

Geological Structures ◽

Public And Private ◽

Public Facilities ◽

Differential Interferometry ◽

Northern Areas ◽

X Band ◽

Land Deformation ◽

The City

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.

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Regional and local land subsidence at the Venice coastland by TerraSAR-X PSI

Proceedings of the International Association of Hydrological Sciences ◽

10.5194/piahs-372-199-2015 ◽

2015 ◽

Vol 372 ◽

pp. 199-205 ◽

Cited By ~ 8

Author(s):

L. Tosi ◽

T. Strozzi ◽

C. Da Lio ◽

P. Teatini

Keyword(s):

Land Subsidence ◽

Regional Scale ◽

Image Resolution ◽

Persistent Scatterer Interferometry ◽

Large Structures ◽

Persistent Scatterer ◽

X Band ◽

High Image Resolution ◽

Under Construction ◽

The City

Abstract. Land subsidence occurred at the Venice coastland over the 2008–2011 period has been investigated by Persistent Scatterer Interferometry (PSI) using a stack of 90 TerraSAR-X stripmap images with a 3 m resolution and a 11-day revisiting time. The regular X-band SAR acquisitions over more than three years coupled with the very-high image resolution has significantly improved the monitoring of ground displacements at regional and local scales, e.g., the entire lagoon, especially the historical palaces, the MoSE large structures under construction at the lagoon inlets to disconnect the lagoon from the Adriatic Sea during high tides, and single small structures scattered within the lagoon environments. Our results show that subsidence is characterized by a certain variability at the regional scale with superimposed important local displacements. The movements range from a gentle uplift to subsidence rates of up to 35 mm yr−1. For instance, settlements of 30–35 mm yr−1 have been detected at the three lagoon inlets in correspondence of the MoSE works, and local sinking bowls up to 10 mm yr−1 connected with the construction of new large buildings or restoration works have been measured in the Venice and Chioggia historical centers. Focusing on the city of Venice, the mean subsidence of 1.1 ± 1.0 mm yr−1 confirms the general stability of the historical center.

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Analyzing Indonesia’s NCICD Project to Stop the Capital City Sinking

Otoritas Jurnal Ilmu Pemerintahan ◽

10.26618/ojip.v7i2.769 ◽

2017 ◽

Vol 7 (2) ◽

Author(s):

Aris Widodo

Keyword(s):

Climate Change ◽

Land Subsidence ◽

City Planning ◽

Land Reclamation ◽

Active Role ◽

Capital City ◽

Indonesian Government ◽

Combat Climate Change ◽

Sea Wall ◽

The City

Jakarta is hit by a tidal flood every year and cause some loss for the city. Beside that flood caused by sea level rise, the city risk on sinking is higher because of land subsidence problem. Without any significant action, it is predicted that Jakarta will face USD 521 million loss risks on 2050 caused by flood. To overcome the sinking problem, Indonesian government plays an active role on the international action to combat climate change. In addition, Indonesian government also implements NCICD project, in which create giant sea wall and land reclamation on the Jakarta Bay. However, the land reclamation raises an argument that it would create an environment disaster for the city. Because of that, it is suggested that Jakarta should only create a sea wall without land reclamation. Moreover, Jakarta government also should ensure that Spatial City Planning and New Rule on ground water extraction are well implemented so the land subsidence in the city is stopped.

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Results of land subsidence measurement using GPS method in the Jakarta groundwater basin in 2015-2019

IOP Conference Series Earth and Environmental Science ◽

10.1088/1755-1315/873/1/012034 ◽

2021 ◽

Vol 873 (1) ◽

pp. 012034

Author(s):

F M Abdullah ◽

H Andriyanto ◽

J R Nababan ◽

F Abdillah ◽

R I H Sulistyawan

Keyword(s):

Ground Water ◽

Land Subsidence ◽

Sea Water ◽

Negative Impact ◽

Average Rate ◽

Soft Soil ◽

Groundwater Basin ◽

Surrounding Areas ◽

Tectonic Forces ◽

The City

Abstract The development of population and development activities in big cities in Indonesia, especially in the city of Jakarta and surrounding areas is very rapid. From several land subsidence studies, several factors have been identified that cause land subsidence, namely: excessive groundwater extraction, reduction due to building/infrastructure loads, subsidence due to natural consolidation of soft soil layers, and subsidence due to tectonic forces. At present the exploitation of ground water for industrial and residential needs is at a level that needs attention. Excessive pumping of groundwater will cause a decrease in the quantity of ground water, entry of seawater into the land (sea water intrusion) and land subsidence. Symptoms of the negative impact of land subsidence have been felt in several areas, especially in industrial areas located in the northern part of Jakarta. This land subsidence can be measured by GPS or satellite geodetic method, which have begun to develop in Indonesia in the past two decades. Measurements were made using the radial method at 53 GPS points in 2015 up to 100 measurement points in 2019 in Jakarta Groundwater Basin. The result of these campaign GPS surveys that is northern part of Jakarta relatively had higher subsidence rate than the southern. The largest subsidence almost reached 6.2 cm/year in Muara Baru in northern area which is southern area only suffered an average rate of 1.16 cm/year.

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Land Subsidence risk maps and InSAR based angular distortion structural vulnerability assessment: an example in Mexico City

Proceedings of the International Association of Hydrological Sciences ◽

10.5194/piahs-382-583-2020 ◽

2020 ◽

Vol 382 ◽

pp. 583-587 ◽

Cited By ~ 2

Author(s):

Enrique Fernández-Torres ◽

Enrique Cabral-Cano ◽

Dario Solano-Rojas ◽

Emre Havazli ◽

Luis Salazar-Tlaczani

Keyword(s):

Mexico City ◽

Land Subsidence ◽

Time Window ◽

Groundwater Resources ◽

Economic Cost ◽

Ground Subsidence ◽

Angular Distortion ◽

Structural Vulnerability ◽

Civil Structures ◽

The City

Abstract. Land subsidence is a phenomenon present in several cities in central Mexico, and results from a combination of groundwater resources' overexploitation and the local stratigraphic nature. Furthermore, subsidence occurs inhomogeneously in space, producing differential vertical displacements, which affect both the natural media, as well as human-built structures. Subsidence associated structural-vulnerability assessments usually rely on direct field measurements to determine parameters such as angular distortion. However, the large areas in which land subsidence occurs (city-scale) in Mexico City hinders a direct quantification of differential displacements for all buildings and structures present in it. A Sentinel-1 based subsidence analysis shows that the highest velocities are located on the eastern sector of the city. This velocity map was used as the basis for a population density weighted land subsidence correlation analysis. Our Land Subsidence Risk assessment indicates that 15.43 % of the population of Mexico City live in intermediate, high and very-high risk zones which corresponds to 1 358 873 inhabitants. Therefore, a significant percentage of Mexico City's population is vulnerable to suffering damage in their housing structures due to land subsidence. Furthermore, the lower income inhabitants share a proportionally greater economic cost due to land subsidence and associated shallow faulting. The structural vulnerability analysis of the civil structures in the city was performed using angular distortion maps derived from the subsidence velocity gradient between October 2014–October 2017 period. These maps indicate that within this time window, ∼12 % of the total urbanized area in Mexico City had already exceeded a 0.002 radian angular distortion threshold; above which damage in civil structures is more likely to occur. In fact, more than 1 million people have already suffered damages in their houses due to the differential ground subsidence and the resulting structural angular distortion. With these results, we can evaluate correspondence between angular distortion map and critical infrastructure of the city, as a result, we found that between 0 % and 12.84 % of these buildings have undergone over 0.002 radian angular distortion.

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Studying Land Subsidence around the City of Shiraz

Scientia Iranica ◽

10.24200/sci.2016.2167 ◽

2016 ◽

Vol 23 (3) ◽

pp. 882-895

Author(s):

H. Rahnema ◽

S. Mirassi

Keyword(s):

Land Subsidence ◽

The City

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