Semarang City is densely inhabited and one of Indonesia's metropolitan cities, as well as the provincial capital of Central Java. Semarang, like the majority of the north coast of Java, has a long and complex history of land subsidence and coastal flooding (in the local language, rob). Northern Semarang, which lies immediately close to the Java Sea, has suffered hundreds of years of sedimentation as a result of coastal processes, resulting in the advancement of the shoreline. The soil layer in the northern portion of Semarang City is formed of Holocene alluvial material that is inherently susceptible to compaction due to the sedimentation process. As a result of changes in land use into residential, industrial, and service districts, alluvial soil originating from the sedimentation process experiences land subsidence due to the weight of buildings, infrastructure, and excessive water pumping. At the same time, due to the tides, locations affected by land subsidence eventually experience coastal flooding. Coastal flooding that occurs along the shore of Semarang is exacerbated by the presence of sea level rise, causing severe damage to local residents. Massive losses ensued from the region's situation, which was marked by coastal flooding and sea level rise.

The purpose of this study was to investigate the long-term impact of excessive water pumping on land subsidence and coastal flooding in Semarang coastal area. Numerous groundwater abstraction scenarios in northern Semarang that resulted in land subsidence were simulated using a numerical model, followed by simulations of several coastal flooding scenarios resulting from land subsidence and sea level rise. This study was carried out by numerically modeling groundwater and land subsidence with MODFLOW and coastal flooding with HEC RAS 2D.

Several boundary conditions and data were used to simulate groundwater, land subsidence, and coastal flooding, after previously making a conceptual model with a grid size of 100 m x 100 m in MODFLOW. In the groundwater and land subsidence model, there are three boundary conditions, i.e. no-flow boundaries, groundwater separation boundaries, and constant head boundaries, whereas the boundary conditions for the coastal flooding model are stage hydrographs derived from tidal data along the coastline and flow hydrographs as upstream boundary conditions for the river. The groundwater and land subsidence model uses rainfall data as recharge, soil characteristics, well placement, and pump discharge, whereas the coastal flooding model uses topographic data derived from the Digital Elevation Model (DEM).

Several simulations of groundwater abstraction were run on the numerical model. The initial simulation is a steady-state groundwater simulation, which will be used to check that the hydrogeological input data is reasonable after the simulation results are verified using recorded groundwater data from six observation wells. Furthermore, groundwater abstraction and land subsidence numerical simulations were performed for transient flow and coastal floods, where groundwater abstraction is scenariod following the trend of the number of registered deep wells in Semarang City and their output capacity that reported from 1900 to 2000. Groundwater level and land subsidence contours will be derived through simulation of groundwater scenarios and used for verification and validation using recorded groundwater data from six observation wells and soil subsidence data from land subsidence monitoring tools. In this study, several sources of land subsidence monitoring data were used, i.e. GPS, and InSAR, where the monitoring data was used as a verifier for the land subsidence simulation. Today, InSAR is one of the trends in the field of geomatics to monitor land subsidence. In contrast to leveling and GPS which must be carried out in the field every year so that it will incur high costs, InSAR is considered a monitoring tool that is cheap, easy, and does not require a long time to get the data.

The next numerical simulations are TS1, TS2, TS3, and TS4, which project land subsidence until 2050. Simulation TS1 is a prediction of land subsidence if the scenario from the initial simulation is executed until 2050. Meanwhile, TS2, TS3, and TS4, are predictions of land subsidence carried out to determine the optimal groundwater management method in reducing land subsidence. Contours of land subsidence due to groundwater abstraction for each scenario are obtained from land subsidence simulation using MODFLOW.

The HEC-RAS 2D coastal flood simulation was performed based on the contours of the previous settlement simulation results. The scenarios used to perform the numerical simulation of coastal flooding are EXT, S1, S3 and S4. The EXT simulation is a numerical simulation of coastal flooding using topographic DEM data published by DEMNAS Indonesia at a resolution of 0.27 arcsec ≈ 8.325 m, with boundary conditions derived from a 25-year return period hydrograph and no SLR tides exist. The EXT scenario is performed by calibrating the estimated land-use roughness coefficient in the study area. While the S1, S3 and S4 simulations are simulations performed on topographic data from the TS1, TS3 and TS4 scenarios respectively by adding a sea level rise scenario by 2050.

The findings revealed that coastal flooding and land subsidence caused by groundwater pumping poses a major hazard to the northern part of Semarang City. Using DEM from DEMNAS in EXT scenario, it can be seen that the area experiencing inundation due to coastal flooding is 76.22 km2. Meanwhile, under the TS1 scenario, the area experiencing land subsidence is 18.76 km2 and the inundated area is 78.65 km2. By implementing a groundwater management scenario that includes a 5% (TS3) and 10% (TS4) reduction in the growth of deep wells and their production capacity between 2035 and 2050, it is possible to control and even restore groundwater in several locations, until the inundation area can be reduced by 21.21% in TS3, and 24.98% in TS4. Therefore, it is possible to lessen land subsidence and coastal flooding, but not eliminate coastal flooding entirely.

Keywords: groundwater abstraction, land subsidence, coastal flooding, numerical model, MODFLOW, HEC-RAS 2D.

Reference
Abidin, H. Z., Andreas, H., Gumilar, I., Sidiq, T. P., &Fukuda, Y. (2013). Land subsidence in coastal city of Semarang (Indonesia): Characteristics, impacts and causes. Geomatics, Natural Hazards and Risk, 4(3), 226–240. https://doi.org/10.1080/19475705.2012.692336
Abidin, H. Z., Andreas, H., Gumilar, I., Sidiq, T. P., Gamal, M., Murdohardono, D., SUpriyadi, S., &Fukuda, Y. (2010). Studying land subsidence in Semarang (Indonesia) using geodetic methods. FIG Congress 2010: Facing the Challenges - Building the Capacity, April 2010, 11–16. https://doi.org/10.1016/j.ssi.2014.10.025
Aditiya, A., Takeuchi, W., &Aoki, Y. (2017). Land Subsidence Monitoring by InSAR Time Series Technique Derived from ALOS-2 PALSAR-2 over Surabaya City, Indonesia. IOP Conference Series: Earth and Environmental Science, 98(1). https://doi.org/10.1088/1755-1315/98/1/012010
Akossou, A. Y. J. (2013). Impact of data structure on the estimators R-square and adjusted R-square in linear regression. International Journal of Mathematics and Computation, January 2013.
Al-Sittawy, M., Gad, S., Fouad, R., &Nofal, E. (2019). Assessment of soil subsidence due to long-term dewatering , Esna city , Egypt. Water Science, 33(1), 40–53. https://doi.org/10.1080/11104929.2019.1630058
Andreas, H., Zainal Abidin, H., Anggreni Sarsito, D., Meilano, I., &Susilo, S. (2019). Investigating the tectonic influence to the anthropogenic subsidence along northern coast of Java Island Indonesia using GNSS data sets. E3S Web of Conferences, 94. https://doi.org/10.1051/e3sconf/20199404005
Avia, L. Q. (2019). Change in rainfall per-decades over Java Island, Indonesia. IOP Conference Series: Earth and Environmental Science, 374(1). https://doi.org/10.1088/1755-1315/374/1/012037
Badan Standardisasi Nasional. (2002). SNI 03-6870: How to test water passing in the laboratory for fine-grained soils with high pressure drops (in Bahasa Indonesia). Badan Standarisasi Nasional.
Badan Standardisasi Nasional. (2008). SNI 3423: How to test soil grain size analysis (in Bahasa Indonesia). Sni, 1–27.
Badan Standardisasi Nasional. (2011). SNI 2812: One-dimensional soil consolidation test method (in Bahasa Indonesia).
Batelaan, O., DeSmedt, F., &Triest, L. (2003). Regional groundwater discharge: Phreatophyte mapping, groundwater modelling and impact analysis of land-use change. Journal of Hydrology, 275(1–2), 86–108. https://doi.org/10.1016/S0022-1694(03)00018-0
Berardino, P., Fornaro, G., Lanari, R., &Sansosti, E. (2002). A new algorithm for surface deformation monitoring based on small baseline differential SAR interferograms. IEEE Transactions on Geoscience and Remote Sensing, 40(11), 2375–2383. https://doi.org/10.1109/TGRS.2002.803792
Betancur, T., Palacio T., C. A., &Escobar M., J. F. (2012). Conceptual Models in Hydrogeology, Methodology and Results. In Hydrogeology - A Global Perspective (Issue July 2014). https://doi.org/10.5772/28155
Bonì, R., Cigna, F., Bricker, S., Meisina, C., &McCormack, H. (2016). Characterisation of hydraulic head changes and aquifer properties in the London Basin using Persistent Scatterer Interferometry ground motion data. Journal of Hydrology, 540, 835–849. https://doi.org/10.1016/j.jhydrol.2016.06.068
Boufekane, A., Saibi, H., Benlaoukli, B., &Saighi, O. (2019). Scenario modeling of the groundwater in a coastal aquifer (Jijel plain area, Algeria). Arabian Journal of Geosciences, 12(24). https://doi.org/10.1007/s12517-019-4965-0
BPBD. (2019). Flood Risk Map.
Bradley, R. M., Weeraratne, S., &Mediwake, T. M. M. (2002). Water use projections in developing countries. Journal American Water Works Association, 94(8), 52–63. https://doi.org/10.1002/j.1551-8833.2002.tb09525.x
Braga, A. C. R., Serrao-Neumann, S., &deOliveira Galvão, C. (2020). Groundwater Management in Coastal Areas through Landscape Scale Planning: A Systematic Literature Review. Environmental Management, 65(3), 321–333. https://doi.org/10.1007/s00267-019-01244-w
Brunner, G. W. (2016). HEC-RAS 5.0 Hydraulic Reference Manual (Issue February, p. 538). https://doi.org/CPD-68
Brunner, G. W., &CEIWR-HEC. (2016). HEC-RAS River Analysis System, 2D Modelling User’s Manual. February, 1442.
Buchori, I., Pramitasari, A., Sugiri, A., Maryono, M., Basuki, Y., &Sejati, A. W. (2018). Adaptation to coastal flooding and inundation: Mitigations and migration pattern in Semarang City, Indonesia. In Ocean and Coastal Management (Vol. 163, pp. 445–455). https://doi.org/10.1016/j.ocecoaman.2018.07.017
Cao, Y., Wei, Y. N., Fan, W., Peng, M., &Bao, L. (2020). Experimental study of land subsidence in response to groundwater withdrawal and recharge in Changping District of Beijing. PLoS ONE, 15(5), 1–17. https://doi.org/10.1371/journal.pone.0232828
Carminati, E., &DiDonato, G. (1999). Separating natural and anthropogenic vertical movements in fast subsiding areas: The Po plain (N. Italy) case. Geophysical Research Letters, 26(15), 2291–2294. https://doi.org/10.1029/1999GL900518
Casulli, V. (2008). A high‐resolution wetting and drying algorithm for free‐surface hydrodynamics. International Journal for Numerical Methods in Fluids, 60, 236–253. https://doi.org/10.1002/fld.1896
Catalão, J., Nico, G., Lollino, P., Conde, V., Lorusso, G., &Silva, C. (2016). Integration of InSAR Analysis and Numerical Modeling for the Assessment of Ground Subsidence in the City of Lisbon, Portugal. IEEE Journal of Selected Topics in Applied Earth Observations and Remote Sensing, 9(4), 1663–1673. https://doi.org/10.1109/JSTARS.2015.2428615
Chen, J., Knight, R., Zebker, H. A., &Schreuder, W. A. (2016). Confined aquifer head measurements and storage properties in the San Luis Valley, Colorado, from spaceborn InSAR observation. Water Resources Research, 52, 3623–3636. https://doi.org/10.1002/2015WR018466
Chen, Y., Xie, W., &Xu, X. (2019). Changes of Population, Built-up Land, and Cropland Exposure to Natural Hazards in China from 1995 to 2015. International Journal of Disaster Risk Science, 10(4), 557–572. https://doi.org/10.1007/s13753-019-00242-0
CTI Engineering International Co., L. & A. (2016). Final Report on Land Subsidence Survey: Part II River Improvement Works, Water Resources Development & Land Subsidence Survey under JICA Loan IP-534.
Custodio, E., Albiac, J., Cermerón, M., Hernández, M., Llamas, M. R., &Sahuquillo, A. (2017). Groundwater mining: benefits, problems and consequences in Spain. Sustainable Water Resources Management, 3(3), 213–226. https://doi.org/10.1007/s40899-017-0099-2
Dawoud, M. A., Darwish, M. M., &El-Kady, M. M. (2005). GIS-based groundwater management model for Western Nile Delta. Water Resources Management, 19(5), 585–604. https://doi.org/10.1007/s11269-005-5603-z
Drias, T., Khedidja, A., Belloula, M., Badraddine, S., &Saibi, H. (2020). Groundwater modelling of the Tebessa-Morsott alluvial aquifer (northeastern Algeria): A geostatistical approach. Groundwater for Sustainable Development, 11, 100444. https://doi.org/10.1016/j.gsd.2020.100444
ElAlfy, M. (2014). Numerical groundwater modelling as an effective tool for management of water resources in arid areas. Hydrological Sciences Journal, 59(6), 1259–1274. https://doi.org/10.1080/02626667.2013.836278
Erkens, G., Bucx, T., Dam, R., DeLange, G., &Lambert, J. (2015). Sinking coastal cities. Proceedings of the International Association of Hydrological Sciences, 372(November), 189–198. https://doi.org/10.5194/piahs-372-189-2015
Galloway, D. L., &Sneed, M. (2013). Analysis and simulation of regional subsidence accompanying groundwater abstraction and compaction of susceptible aquifer systems in the USA. Boletin de La Sociedad Geologica Mexicana, 65(1), 123–136. https://doi.org/10.18268/BSGM2013v65n1a10
Gambolati, G., Teatini, P., Tomasi, L., &Gonella, M. (1999). Coastline regression of the Romagna region, Italy, due to natural and anthropogenic land subsidence and sea level rise. Water Resources Research, 35(1), 163–184. https://doi.org/10.1029/1998WR900031
Ghifari, I. A. (2021). Design of Extreme Rain Value by Considering Climate Change in Java Island (Undergraduate Thesis, in Bahasa Indonesia). Universitas Jenderal Soedirman.
Gogu, R. C., Carabin, G., Hallet, V., Peters, V., &Dassargues, A. (2001). GIS-based hydrogeological databases and groundwater modelling. Hydrogeology Journal, 9(6), 555–569. https://doi.org/10.1007/s10040-001-0167-3
Gonçalves, R. D., Teramoto, E. H., &Chang, H. K. (2020). Regional groundwater modeling of the guarani aquifer system. Water (Switzerland), 12(9), 1–12. https://doi.org/10.3390/W12092323
Gong, X., Geng, J., Sun, Q., Gu, C., &Zhang, W. (2020). Experimental study on pumping-induced land subsidence and earth fissures: a case study in the Su-Xi-Chang region, China. Bulletin of Engineering Geology and the Environment, 79(9), 4515–4525. https://doi.org/10.1007/s10064-020-01864-1
Gorelick, S. M., &Zheng, C. (2015). Global change and the groundwater management challenge. Water Resources Research, 51, 3031–3051. https://doi.org/10.1002/2014WR016825
Gumilar, I., Abidin, H. Z., Sidiq, T. P., Andreas, H., Maiyudi, R., &Gamal, M. (2013). Mapping And Evaluating The Impact Of Land Subsidence In Semarang (Indonesia). Indonesian Journal of Geospatial, 2(2), 26-41–41.
Handayani, W., Chigbu, U. E., Rudiarto, I., &Surya Putri, I. H. (2020). Urbanization and increasing flood risk in the Northern Coast of Central Java-Indonesia: An assessment towards better land use policy and flood management. Land, 9(10). https://doi.org/10.3390/LAND9100343
Hanson, S., Nicholls, R., Ranger, N., Hallegatte, S., Corfee-Morlot, J., Herweijer, C., &Chateau, J. (2011). A global ranking of port cities with high exposure to climate extremes. Climatic Change, 104(1), 89–111. https://doi.org/10.1007/s10584-010-9977-4
Harwitasari, D. (2009). Adaptation Responses to Tidal Flooding in Semarang, Indonesia. October 2008. http://thesis.eur.nl/pub/12145/(1)33555.pdf
Harwitasari, D., &vanAst, J. A. (2011). Climate change adaptation in practice: People’s responses to tidal flooding in Semarang, Indonesia. Journal of Flood Risk Management, 4(3), 216–233. https://doi.org/10.1111/j.1753-318X.2011.01104.x
Holzer, T. L., &Galloway, D. L. (2005). Impacts of land subsidence caused by withdrawal of underground fluids in the United States. In REVIEWS IN ENGINEERING GEOLOGY: Humans as Geologic Agents: Vol. XVI (Issue 08, pp. 87–99). https://doi.org/10.1130/2005.4016(08)
Hooper, A., Zebker, H., Segall, P., &Kampes, B. (2004). A new method for measuring deformation on volcanoes and other natural terrains using InSAR persistent scatterers. Geophysical Research Letters, 31(23), 1–5. https://doi.org/10.1029/2004GL021737
https://semarangkota.bps.go.id/. (2021). Semarang City’s Central Statistics Agency.
Hu, J., Li, Z. W., Ding, X. L., Zhu, J. J., Zhang, L., &Sun, Q. (2014). Resolving three-dimensional surface displacements from InSAR measurements: A review. Earth-Science Reviews, 133, 1–17. https://doi.org/10.1016/j.earscirev.2014.02.005
Hu, R. L., Yue, Z. Q., Wang, L. C., &Wang, S. J. (2004). Review on current status and challenging issues of land subsidence in China. Engineering Geology, 76(1–2), 65–77. https://doi.org/10.1016/j.enggeo.2004.06.006
Hung, W. C., Hwang, C., Liou, J. C., Lin, Y. S., &Yang, H. L. (2012). Modeling aquifer-system compaction and predicting land subsidence in central Taiwan. Engineering Geology, 147–148, 78–90. https://doi.org/10.1016/j.enggeo.2012.07.018
ICCSR. (2010). Indonesia Climate Change Sectoral Roadmap (ICCSR).
IPCC. (2021). Summary for Policymakers. In: Climate Change 2021: The Physical Science Basis. Contribution of Working Group I to the Sixth Assessment Report of the Intergovernmental Panel on Climate Change. In Energy and Environment (Vol. 18, Issues 3–4). IPCC. https://doi.org/10.1260/095830507781076194
Jia, H., &Liu, L. (2016). A technical review on persistent scatterer interferometry. Journal of Modern Transportation, 24(2), 153–158. https://doi.org/10.1007/s40534-016-0108-4
Johnston, J., Cassalho, F., Miesse, T., &Ferreira, C. M. (2021). Projecting the effects of land subsidence and sea level rise on storm surge flooding in Coastal North Carolina. Scientific Reports, 11(1), 1–13. https://doi.org/10.1038/s41598-021-01096-7
Kalyanapu, A. J., Burian, S. J., &McPherson, T. N. (2009). Effect of land use-based surface roughness on hydrologic model output. Journal of Spatial Hydrology, 9(2), 51–71.
Kasuya, E. (2019). On the use of r and r squared in correlation and regression. Ecological Research, 34(1), 235–236. https://doi.org/10.1111/1440-1703.1011
Kirezci, E., Young, I. R., Ranasinghe, R., Muis, S., Nicholls, R. J., Lincke, D., &Hinkel, J. (2020). Projections of global-scale extreme sea levels and resulting episodic coastal flooding over the 21st Century. Scientific Reports, 10(1), 1–12. https://doi.org/10.1038/s41598-020-67736-6
Kuehn, F., Albiol, D., Cooksley, G., Duro, J., Granda, J., Haas, S., Hoffmann-Rothe, A., &Murdohardono, D. (2010). Detection of land subsidence in Semarang, Indonesia, using stable points network (SPN) technique. Environmental Earth Sciences, 60(5), 909–921. https://doi.org/10.1007/s12665-009-0227-x
Kulp, S. A., &Strauss, B. H. (2019). New elevation data triple estimates of global vulnerability to sea-level rise and coastal flooding. Nature Communications, 10(1). https://doi.org/10.1038/s41467-019-12808-z
Lanari, R., Casu, F., Manzo, M., &Lundgren, P. (2007). Application of the SBAS-DInSAR technique to fault creep: A case study of the Hayward fault, California. Remote Sensing of Environment, 109(1), 20–28. https://doi.org/10.1016/j.rse.2006.12.003
Lea, D., Yeonsu, K., &Hyunuk, A. (2019). Case study of HEC-RAS 1D-2D coupling simulation: 2002 Baeksan flood event in Korea. Water (Switzerland), 11(10), 1–14. https://doi.org/10.3390/w11102048
Lo, W. C., Borja, R. I., Deng, J. H., &Lee, J. W. (2020). Analytical solution of soil deformation and fluid pressure change for a two-layer system with an upper unsaturated soil and a lower saturated soil under external loading. In J. Hydrol (Vol. 588). https://doi.org/10.1016/j.jhydrol.2020.124997
Lo, W. C., Borja, R. I., Deng, J. H., &Lee, J. W. (2021). Poroelastic theory of consolidation for a two-layer system with an upper unsaturated soil and a lower saturated soil under fully permeable boundary conditions. J. Hydrol, 596(October 2020), 125700. https://doi.org/10.1016/j.jhydrol.2020.125700
Lo, W. C., Chao, N. C., Chen, C. H., &Lee, J. W. (2017). Poroelastic theory of consolidation in unsaturated soils incorporating gravitational body forces. Advances in Water Resources, 106, 121–131. https://doi.org/10.1016/j.advwatres.2017.03.006
Lo, W. C., &Lee, J. W. (2015). Effect of water content and soil texture on consolidation in unsaturated soils. In Advances in Water Resources (Vol. 82, pp. 51–69). https://doi.org/10.1016/j.advwatres.2015.04.004
Lo, W. C., Purnomo, S. N., Dewanto, B. G., &Sarah, D. (2022). Integration of Numerical Models and InSAR Techniques to Assess Land Subsidence Due to Excessive Groundwater Abstraction in the Coastal and Lowland Regions of Semarang City. Water, 14(2), 201.
Lo, W. C., Purnomo, S. N., Sarah, D., Aghnia, S., &Hardini, P. (2021). Groundwater Modelling in Urban Development to Achieve Sustainability of Groundwater Resources: A Case Study of Semarang City, Indonesia. Water, 13(10), 1395. https://doi.org/10.3390/w13101395
Lo, W. C., Sposito, G., Lee, J. W., &Chu, H. (2016). One-dimensional consolidation in unsaturated soils under cyclic loading. Advances in Water Resources, 91, 122–137. https://doi.org/10.1016/j.advwatres.2016.03.001
Loáiciga, H. A. (2013). Consolidation Settlement in Aquifers Caused by Pumping. Journal of Geotechnical and Geoenvironmental Engineering, 139(7), 1191–1204. https://doi.org/10.1061/(asce)gt.1943-5606.0000836
Lubis, A. M., Sato, T., Tomiyama, N., Isezaki, N., &Yamanokuchi, T. (2011). Ground subsidence in Semarang-Indonesia investigated by ALOS-PALSAR satellite SAR interferometry. Journal of Asian Earth Sciences, 40(5), 1079–1088. https://doi.org/10.1016/j.jseaes.2010.12.001
Luo, Q., Perissin, D., Lin, H., Zhang, Y., &Wang, W. (2014). Subsidence monitoring of tianjin suburbs by TerraSAR-X persistent scatterers interferometry. IEEE Journal of Selected Topics in Applied Earth Observations and Remote Sensing, 7(5), 1642–1650. https://doi.org/10.1109/JSTARS.2013.2271501
Mahmoudpour, M., &Khamehchiyan, M. (2018). Numerical simulation and prediction of regional land subsidence caused by groundwater exploitation in the southwest plain of Tehran , Iran. Engineering Geology, 201(2016), 6–28. https://doi.org/10.1016/j.enggeo.2015.12.004
Marfai, M. A., &King, L. (2007). Monitoring land subsidence in Semarang , Indonesia. Environmental Geology, 53, 651–659. https://doi.org/10.1007/s00254-007-0680-3
Marfai, M. A., &King, L. (2008). Coastal flood management in Semarang , Indonesia. Enironmental Geology, 55, 1507–1518. https://doi.org/10.1007/s00254-007-1101-3
Margat, J., &Jac van der Gun. (2013). Groundwater around the World: A Geographic Synopsis. CRC Press, Taylor & Francis Group.
Marsudi. (2000). Prediction of Land Subsidence Rate in Semarang Alluvial Plain, Central Java Province (In Bahasa Indonesia). Institut Teknologi Bandung.
Mateos, R. M., Ezquerro, P., Luque-Espinar, J. A., Béjar-Pizarro, M., Notti, D., Azañón, J. M., Montserrat, O., Herrera, G., Fernández-Chacón, F., Peinado, T., Galve, J. P., Pérez-Peña, V., Fernández-Merodo, J. A., &Jiménez, J. (2017). Multiband PSInSAR and long-period monitoring of land subsidence in a strategic detrital aquifer (Vega de Granada, SE Spain): An approach to support management decisions. Journal of Hydrology, 553, 71–87. https://doi.org/10.1016/j.jhydrol.2017.07.056
McDonald, M. G., &Harbaugh, A. W. (1984). A modular three-dimensional finite-difference groundwater flow model. https://doi.org/10.1016/0022-1694(86)90106-x
McDonald, R. I., Green, P., Balk, D., Fekete, B. M., Revenga, C., Todd, M., &Montgomery, M. (2011). Urban growth, climate change, and freshwater availability. Proceedings of the National Academy of Sciences of the United States of America, 108(15), 6312–6317. https://doi.org/10.1073/pnas.1011615108
McDonald, R. I., Weber, K., Padowski, J., Flörke, M., Schneider, C., Green, P. A., Gleeson, T., Eckman, S., Lehner, B., Balk, D., Boucher, T., Grill, G., &Montgomery, M. (2014). Water on an urban planet: Urbanization and the reach of urban water infrastructure. Global Environmental Change, 27(1), 96–105. https://doi.org/10.1016/j.gloenvcha.2014.04.022
McGrane, S. J. (2016). Impacts of urbanisation on hydrological and water quality dynamics, and urban water management: a review. Hydrological Sciences Journal, 61(13), 2295–2311. https://doi.org/10.1080/02626667.2015.1128084
Milne, G. A., Gehrels, W. R., Hughes, C. W., &Tamisiea, M. E. (2009). Identifying the causes of sea-level change. Nature Geoscience, 2(7), 471–478. https://doi.org/10.1038/ngeo544
Mining and Energy Agency Central Java Province (DESDM Provinsi Jawa Tengah). (2012). Recapitulation of water calculation and water acquisition value 2001 - 2010. Internal report (unpublished) in Bahasa Indonesia.
Mining and Energy Agency of Central Java Province and Directorate of Geological Environment and Mining Areas. (2003). Overview of Groundwater System Configuration (in Bahasa Indonesia). In Final Report: Study on the Configuration and Zoning of Underground Water in the Semarang - Demak, Subah, and Karanganyar - Boyolali, Central Java Province. Mining and Energy Agency of Central Java Province.
Molle, F., López-Gunn, E., &vanSteenbergen, F. (2018). The local and national politics of groundwater overexploitation. Water Alternatives, 11(3), 445–457.
Moraes, D. (2012). The Coefficient of Determination : What. Investigative Ophtalmology & Visual Science, 53(11), 6830–6832.
Morishita, Y., Lazecky, M., Wright, T. J., Weiss, J. R., Elliott, J. R., &Hooper, A. (2020). LiCSBAS: An open-source insar time series analysis package integrated with the LiCSAR automated sentinel-1 InSAR processor. Remote Sensing, 12(3), 5–8. https://doi.org/10.3390/rs12030424
Morris, B. L., Lawrence, A. R. L., Chilton, P. J. C., Adams, B., Calow R C, &Klinck, B. A. (2003). Groundwater and its Susceptibility to Degradation: A Global Assessment of the Problem and Options for Management. Early Warning and Assessment Report Series, RS. 03-3.
Motagh, M., Djamour, Y., Walter, T. R., Wetzel, H. U., Zschau, J., &Arabi, S. (2007). Land subsidence in Mashhad Valley, northeast Iran: Results from InSAR, levelling and GPS. Geophysical Journal International, 168(2), 518–526. https://doi.org/10.1111/j.1365-246X.2006.03246.x
Mulyana, W., Setiono, I., Selzer, A. K., Zhang, S., Dodman, D., &Schensul, D. (2013). UNFPA Urbanization and Emerging Population Issues: Urbanisation, Demographics and Adaptation to Climate Change in Semarang, Indonesia (Issue September 2013). http://www.iied.org/pubs/display.php?o=10632IIED
National Oceanic and Atmospheric Administration (NOAA). (2022). NOAA Tsunami Program. https://www.tsunami.noaa.gov/
Neill, S. P., &Hashemi, M. R. (2018). Ocean Modelling for Resource Characterization. In Fundamentals of Ocean Renewable Energy. https://doi.org/10.1016/b978-0-12-810448-4.00008-2
NOAA. (2022a). Change in mean sea level in Indonesia.
NOAA. (2022b). Global Mean Sea Level.
Othman, A., &Abotalib, A. Z. (2019). Land subsidence triggered by groundwater withdrawal under hyper ‑ arid conditions : case study from Central Saudi Arabia. Environmental Earth Sciences, 78(243), 1–8. https://doi.org/10.1007/s12665-019-8254-8
Pastore, N., Claudia Cherubini, &Angelo Doglioni. (2020). Modelling of the Complex Groundwater Level Dynamics during Episodic Rainfall Events of a Surficial Aquifer in Southern Italy. 1–21.
Poland, J. F. (1984). Guidebook to studies of land subsidence due to ground-water withdrawal (J. F.Poland (ed.)). United Nations Educational, Scientific and Cultural Organization.
Purnomo, S. N., &Lo, W. C. (2020). Estimation of Groundwater Recharge in Semarang City, Indonesia. IOP Conference Series: Materials Science and Engineering, 982(1). https://doi.org/10.1088/1757-899X/982/1/012035
Purnomo, S. N., &Widiyanto, W. (2014). Effect of Rainfall Distribution Pattern on Water Level Profile in Opak River. Forum Teknik Sipil, 2.
PUSGEN, (Pusat Studi Gempa Nasional) Pusat Litbang Perumahan dan Permukiman. (2017). Peta Sumber Dan Bahaya Gempa Indonesia Tahun 2017 (Map of Indonesia Earthquake Sources and Hazards in 2017). In Pusat Penelitian dan Pengembangan Perumahan Pemukiman, Badan Penelitian dan Pengembangan Kementerian Pekerjaan Umum dan Perumahan Rakyat.
Rezaei, A., Mousavi, Z., Khorrami, F., &Nankali, H. (2020). Inelastic and elastic storage properties and daily hydraulic head estimates from continuous global positioning system (GPS) measurements in northern Iran. Hydrogeology Journal, 28(2), 657–672. https://doi.org/10.1007/s10040-019-02092-y
Rojas, R., Kahunde, S., Peeters, L., Batelaan, O., Feyen, L., &Dassargues, A. (2010). Application of a multimodel approach to account for conceptual model and scenario uncertainties in groundwater modelling. Journal of Hydrology, 394(3–4), 416–435. https://doi.org/10.1016/j.jhydrol.2010.09.016
Rukayah, R. S., &Abdullah, M. (2019). The Glory of Semarang Coastal City in the Past, Multi-Ethnic Merchants and Dutch Commerce. Journal of Southwest Jiaotong University, 54(6). https://doi.org/10.35741/issn.0258-2724.54.6.42
Saha, G. C., &Quinn, M. (2020). Numerical modelling of the impacts of water abstraction for hydraulic fracturing on groundwater–surface water interaction: a case study from northwestern Alberta, Canada. Hydrological Sciences Journal, 65(12), 2142–2158. https://doi.org/10.1080/02626667.2020.1797044
Samsonov, S., d’Oreye, N., &Smets, B. (2013). Ground deformation associated with post-mining activity at the French-German border revealed by novel InSAR time series method. In International Journal of Applied Earth Observation and Geoinformation (Vol. 23, Issue 1, pp. 142–154). https://doi.org/10.1016/j.jag.2012.12.008
Sarah, D. (2019). Natural Compaction of Semarang Demak Alluvial Deposit. (Unpublished). Institut Teknologi Bandung.
Sarah, D., Hutasoit, L. ., Delinom, R. ., &Sadisun, I. . (2020a). Natural Compaction of Semarang Demak Alluvial Plain and Its Relationship to the Present Land Subsidence. Indonesian Journal on Geoscience, 7(3), 273–289. https://doi.org/10.17014/ijog.7.3.273-289
Sarah, D., Hutasoit, L. M., Delinom, R. M., &Sadisun, I. A. (2020b). Natural Compaction of Semarang-Demak Alluvial Plain and Its Relationship to the Present Land Subsidence. Indonesian Journal on Geoscience, 7(3), 273–289. https://doi.org/10.17014/ijog.7.3.273-289
Satyaji Rao, Y. R., &Siva Prasad, Y. (2020). Groundwater flow modeling - A tool for water resources management in the khondalite and sandstone formations. Groundwater for Sustainable Development, 11(April), 100454. https://doi.org/10.1016/j.gsd.2020.100454
Semarang Central Bureau of Statistic. (2021). Semarang municipalty in figures 2021. Badan Pusat Statistik Jawa Tengah.
Spatial Plans of Semarang City 2011-2031 (in Bahasa Indonesia), Peraturan Daerah Kota Semarang 1 (2010).
Semarang City Government. (2011). Urban Planning of Semarang City 2011 - 2031.
Shen, S. L., Xu, Y. S., &Hong, Z. S. (2006). Estimation of land subsidence based on groundwater flow model. Marine Georesources and Geotechnology, 24(2), 149–167. https://doi.org/10.1080/10641190600704848
Shen, S., &Xu, Y. (2011). Numerical evaluation of land subsidence induced by groundwater pumping in Shanghai. 1392(July), 1378–1392. https://doi.org/10.1139/T11-049
Singh, A. (2013). Groundwater modelling for the assessment of water management alternatives. Journal of Hydrology, 481, 220–229. https://doi.org/10.1016/j.jhydrol.2012.12.042
Siswanto, S., &Supari, S. (2015). Rainfall Changes over Java Island, Indonesia. Journal of Environment and Earth Science, 5(14), 1–10. www.iiste.org
Sri Harto. (1985). Study of The Unit Hydrograph Basic Characteristics of Rivers on the Island of Jawa for Flood Estimation. Universitas Gadjah Muda, Yogyakarta.
Sri Harto. (2000). Hydrology-Theory, Problem, Solution (in Bahasa Indonesia). Nafiri Offset.
Sri Harto. (2016). Review of Rainfall Hourly Distribution on the Island of Java. Journal of the Civil Engineering Forum, 2(1), 145. https://doi.org/10.22146/jcef.26479
Sukoso, E. (2004). Comparison of the Accuracy of Rainfall Hourly Distribution on the Design Hydrograph (in Bahasa Indonesia). Universitas Gadjah Mada, Yogyakarta, Indonesia.
Suryanti, E. D., &Marfai, M. A. (2008). Adaptation of the coastal area of Semarang to the danger of tidal flooding (Rob). Jurnal Kebencanaan Indonesia, 1(5), 335–346.
Susanti, B. T., Dewi, D. Y. T. N., &Sunarimahingsih, I. Y. T. (2018). Developing a Disaster Risk Reduction Strategy for Semarang Old Town. 56.
Taherkhani, M., Vitousek, S., Barnard, P. L., Frazer, N., Anderson, T. R., &Fletcher, C. H. (2020). Sea-level rise exponentially increases coastal flood frequency. Scientific Reports, 10(1), 1–17. https://doi.org/10.1038/s41598-020-62188-4
Tanimoto, T. (1969). Revised and Enlarge Edition of the Hourly Rainfall Analysis in Java. Institut Teknologi Bandung.
Teatini, P., Tosi, L., &Strozzi, T. (2011). Quantitative evidence that compaction of Holocene sediments drives the present land subsidence of the Po Delta, Italy. Journal of Geophysical Research: Solid Earth, 116(8), 1–10. https://doi.org/10.1029/2010JB008122
Thaden, R. E., Sumardirdja, H., &Richards, P. W. (1996). Geological map of Semarang- Magelang Quadrangle, Java, scale 1:100.000.
Thu, T. M., &Fredlund, D. G. (2000). Modelling subsidence in the Hanoi City area, Vietnam. Canadian Geotechnical Journal, 37(3), 621–637. https://doi.org/10.1139/t99-126
Tirtomihardjo, H. (2011). Groundwater Resource Potential in Indonesia and Their Management.
Tobing, M. H. L., Syarief, E. A., &Murdohardono, D. (2000). Engineering geological investigation of subsidence in Semarang and its surroundings, Central Java Province (in Bahasa Indonesia).
Tran, D. H., &Wang, S. J. (2020). Land subsidence due to groundwater extraction and tectonic activity in Pingtung Plain, Taiwan. Proceedings of the International Association of Hydrological Sciences, 382, 361–365. https://doi.org/10.5194/piahs-382-361-2020
Triatmodjo, B. (2008). Applied Hydrology (in Bahasa Indonesia) (1st ed.). Beta Offset.
Turner, S. W. D., Hejazi, M., Yonkofski, C., Kim, S. H., &Kyle, P. (2019). Influence of Groundwater Extraction Costs and Resource Depletion Limits on Simulated Global Nonrenewable Water Withdrawals Over the Twenty-First Century. Earth’s Future, 7(2), 123–135. https://doi.org/10.1029/2018EF001105
U.S. Army Corps of Engineers. (2021). Creating Land Cover, Manning’s n Values, and Impervious Layers. In U.S. Army Corps of Engineers (Ed.), HEC-RAS 2D User’s Manual (6th ed.). U.S. Army Corps of Engineers.
United Nations. (2018). https://www.un.org/en/development/desa/population/theme/urbanization/index.asp.
USGS. (1999). Land Subsidence in the United States (D.Galloway, D. R.David R. Jones, &S. E.Ingebritsen (eds.)). USGS Circular.
USGS. (2019). National Land Cover Database Class Legend and Description.
VanBemmelen, R. W. (1949). The Geology of Indonesia. General Geology of Indonesia and Adjacent Archipelagoes. In Government Printing Office, The Hague (pp. 545–547; 561–562).
Wang, Q., Yu, W., Xu, B., &Wei, G. (2019). Assessing the use of gacos products for sbas-insar deformation monitoring: A case in southern california. Sensors (Switzerland), 19(18). https://doi.org/10.3390/s19183894
Yan, S., Liu, G., Deng, K., Wang, Y., Zhang, S., &Zhao, F. (2016). Large deformation monitoring over a coal mining region using pixel-tracking method with high-resolution Radarsat-2 imagery. Remote Sensing Letters, 7(3), 219–228. https://doi.org/10.1080/2150704X.2015.1126683
Yang, Q., &Ke, Y. (2017). Relationship between urban construction and land subsidence in Beijing region. Proceedings - 22nd International Congress on Modelling and Simulation, MODSIM 2017, December, 1020–1026. https://doi.org/10.36334/modsim.2017.h4.yang
Yi, S., Wang, Q., &Sun, W. (2014). Predictability of hydraulic head changes and characterization of aquifer system and fault properties from InSAR derived ground deformation. Journal of Geophysical Research: Solid Earth, 119, 6572–6590. https://doi.org/10.1002/2014JB011266
Zeitoun, D. G., &Wakshal, E. (2013). Land Subsidence Analysis in Urban Areas. Springer.
Zhang, Y., Liu, Y., Jin, M., Jing, Y., Liu, Y., Liu, Y., Sun, W., Wei, J., &Chen, Y. (2019). Monitoring land subsidence in wuhan city (China) using the SBAS-INSAR method with radarsat-2 imagery data. Sensors (Switzerland), 19(3). https://doi.org/10.3390/s19030743
Zhang, Y., Xue, Y., Wu, J., Wang, H., &He, J. (2012). Mechanical modeling of aquifer sands under long-term groundwater withdrawal. Engineering Geology, 125, 74–80. https://doi.org/10.1016/j.enggeo.2011.11.006
Zoccarato, C., Minderhoud, P. S. J., &Teatini, P. (2018). The role of sedimentation and natural compaction in a prograding delta: insights from the mega Mekong delta, Vietnam. Scientific Reports, 8(1). https://doi.org/10.1038/s41598-018-29734-7
Zope, P. E., Eldho, T. I., &Jothiprakash, V. (2016). Impacts of land use-land cover change and urbanization on flooding: A case study of Oshiwara River Basin in Mumbai, India. Catena, 145, 142–154. https://doi.org/10.1016/j.catena.2016.06.009