Numerical Modeling of Salinity Intrusion in Balikpapan Bay: Assessing the Impact of Upstream River Discharge Scenarios
DOI:
https://doi.org/10.30872/1ntqk236Keywords:
Balikpapan Bay, HAMSOM, Saltwater Surface Intrusion, River Discharge Scenarios, Nusantara Capital CityAbstract
Balikpapan Bay, situated in the rapidly evolving Nusantara Capital Region, is significantly susceptible to alterations in freshwater influx resulting from dam construction and the reduction of river discharge. This study utilizes the three-dimensional baroclinic Hamburg Shelf Ocean Model (HAMSOM) to simulate hydrodynamics, temperature, and salinity across various river discharge scenarios. Model validation shows that the model is good enough at capturing the bay's physical processes. The RMSE values are 0.1 m for sea level, 0.1 m/s for current speed, 0.67 psu for salinity, and 1.41°C for temperature. The correlation coefficients are between 0.85 and 0.99. Then, the 50% decrease in discharge raises salinity levels throughout the estuaries. Then a 95% decrease of river discharge leads to long-lasting saline intrusion levels of 34–36 psu. This effect was observed even in areas that are typically dominated by freshwater. The spatial analysis shows that when there is less flow, the system changes to a state where tides are more dominated and marine intrusion is more common. As a result, the influence of freshwater diminishes. These results show how important it is to keep the river discharge at the right level to keep the estuarine balance. They also show how important it is to manage water resources in a way that considers rapid regional growth for environmental sustainability.
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[1]. Hermansyah, H., Sari Ningsih, N., Nabil, N., Tarya, A. and Syahruddin, S. (2020), Numerical Modeling of Tidal Current Patterns Using 3 Dimensional MOHID in Balikpapan Bay, Indonesia, Jurnal Ilmiah Perikanan dan Kelautan, 12(1), 9–20. https://doi.org/10.20473/jipk.v12i1.16257
[2]. Nur, A. A., Mandang, I., Mubarrok, S. and Riza, M. (2018), The Changes of Water Mass Characteristics Using 3 Dimensional Regional Ocean Modeling System (ROMS) in Balikpapan Bay, Indonesia, IOP Conference Series: Earth and Environmental Science, 162, 012006. https://doi.org/10.1088/1755-1315/162/1/012006
[3]. Putri, M. R., Anwar, I. P., Sihotang, Z., Bernawis, L. I., Setiawan, A., Riza, M., Mandang, I. and Tatipatta, W. M. (2021), Observation and Numerical Modeling of Physical Oceanography in the Balikpapan Bay, East Kalimantan: Preliminary Results, Depik, 10(2), 130–135. https://doi.org/10.13170/depik.10.2.19259
[4]. Gade, M., Mayer, B., Meier, C., Pohlmann, T., Putri, M. and Setiawan, A. (2017), Oil Pollution in Indonesian Waters: Combining Statistical Analyses of Envisat ASAR and Sentinel 1A C SAR Data with Numerical Tracer Modelling, ISPRS Archives, XLII-3/W2, 71–77. https://doi.org/10.5194/isprs-archives-XLII-3-W2-71-2017
[5]. Septiardi, M. E. and Natalisanto, A. I. (2019), Studi Pemanfaatan Air Tanah dan Potensi Intrusi Air Laut di Daerah Pesisir Kota Balikpapan, Jurnal Teknik Lingkungan, 7, 1–12.
[6]. RILIS PUPR (2019), Bendungan Sepaku Semoi Mulai Dibangun Tahun 2020 Untuk Dukung Kebutuhan Air Baku IKN, SP. BIRKOM/XII/2019/587, p. 5.
[7]. PUSHIDROS AL (2018), Naval Chart of Balikpapan Bay.
[8]. Putri, M. R. (2005), Study of Ocean Climate Variability (1959–2002) in the Eastern Indian Ocean, Java Sea and Sunda Strait Using the HAMburg Shelf Ocean Model, Dissertation, Staats und Universitätsbibliothek Hamburg Carl von Ossietzky. https://ediss.sub.uni-hamburg.de/handle/ediss/911
[9]. Anwar, I. P., Putri, M. R. and Setiawan, A. (2018), Ocean Numerical Model Experiment on Estimating the Variation of Volume and Heat Transport in Karimova Strait, IOP Conference Series: Earth and Environmental Science, 162, 012001. https://doi.org/10.1088/1755-1315/162/1/012001.
[10]. Mayer, B. and Damm, P. E. (2012), The Makassar Strait Throughflow and Its Jet, Journal of Geophysical Research: Oceans, 117(C7). https://doi.org/10.1029/2011JC007809
[11]. Putri, M. R., Setiawan, A., Sari, T., Mayer, B. and Pohlmann, T. (2018), Trajectory Model for Identification of Oil Spill Around the Coast of Pari Island, Seribu Islands, North Jakarta, Jurnal Ilmu dan Teknologi Kelautan Tropis, 9(2), 657–664. https://doi.org/10.29244/jitkt.v9i2.19299
[12]. Nurfitri, S., Basit, A., Putri, M. R., Pätsch, J. and Pohlmann, T. (2020), A Lagrangian Study of Upwelled Waters in the Northern Arafura Sea, IOP Conference Series: Earth and Environmental Science, 618(1), 012022. https://doi.org/10.1088/1755-1315/618/1/012022.
[13]. Egbert, G. D. and Erofeeva, S. Y. (2002), Efficient Inverse Modeling of Barotropic Ocean Tides, Journal of Atmospheric and Oceanic Technology, 19(2), 183–204. https://doi.org/10.1175/1520-0426(2002)019<0183:EIMOBO>2.0.CO;2
[14]. Kanamitsu, M., Ebisuzaki, W., Woollen, J., Yang, S.-K., Hnilo, J. J., Fiorino, M. and Potter, G. L. (2002), NCEP–DOE AMIP II Reanalysis (R 2), Bulletin of the American Meteorological Society, 83(11), 1631–1644. https://doi.org/10.1175/BAMS-83-11-1631.
[15]. Mishonov, A. (2018), NOAA Atlas NESDIS 61.
[16]. Nurjaya, I. W., Surbakti, H., Hartanto, M. T., Jonson, L. G. and Sulardi, A. (2018), Water Mass Dynamics in Balikpapan Bay, Eastern Kalimantan Indonesia, IOP Conference Series: Earth and Environmental Science, 176, 012019. https://doi.org/10.1088/1755-1315/176/1/012019.
[17]. Anwar, I. P., Putri, M. R., Tarya, A., Mandang, I., Setiawan, A. and Tatipatta, W. M. (2021), Analysis of Current Dynamics in Indonesian Estuaries, IOP Conference Series: Earth and Environmental Science, 925, 012013. https://doi.org/10.1088/1755-1315/925/1/012013.
[18]. Valle-Levinson, A. (2010), Contemporary Issues in Estuarine Physics, Cambridge University Press.
[19]. Pugh, D. T. and Woodworth, P. (2014), Sea-Level Science, Cambridge University Press.
[20]. Putri, M. R., Sari, T., Anwar, I. P., Mandang, I., Setiawan, A. and Tatipatta, W. M. (2021), Analysis of Sea Level Changes in Balikpapan Bay as Basic Data for Strategic Planning the New Capital City of Republic of Indonesia, Journal of Physics: Conference Series, 1763(1), 012043. https://doi.org/10.1088/1742-6596/1763/1/012043
[21]. Anwar, I. P., Putri, M. R., Setiawan, A., Tarya, A., Mandang, I., Nurfitri, S. and Tatipatta, W. M. (2023), Detecting Chlorophyll a Concentration and Bloom Patterns in the Coastal Area Around Indonesia's New Capital City (Nusantara) Using Ocean Color Reanalysis Data, Aquaculture, Aquarium, Conservation & Legislation (AACL) Bioflux, 16(4), 2349–2368.
[22]. Anwar, I. P., Putri, M. R., Setiawan, A., Tarya, A., Mandang, I., Nurfitri, S. and Purnaningtyas, D. W. (2024), Assessment of Phytoplankton Community and Diversity Dynamics on the Neap Tide in Balikpapan Bay, East Kalimantan, Indonesia, Polish Journal of Environmental Studies, 33(1), 77–88. https://doi.org/10.15244/pjoes/168107
[23]. Anwar, I. P., Herho, S. H. S., Khadami, F., Putri, M. R. and Syahrial, S. C. (2026), Towards Statistical Modeling of Chlorophyll a Concentrations in Balikpapan Bay, Indonesia: Implications for Algal Bloom Detection, Environmental Research Communications, 8(2), 025027. https://doi.org/10.1088/2515-7620/ae4680.
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