Correlation between household connections and influent domestic wastewater characteristics: Evidence from a small island WWTP on Tidung Besar Island, Indonesia: Hubungan antara jumlah sambungan rumah tangga dan karakteristik air limbah domestik yang masuk: Bukti dari IPAL di Pulau Tidung Besar, Indonesia

Gatot Prayoga; Rizki Moch Rijaldi; Rizqi Fahma Sidik; Hefni Effendi; Gatot Yulianto

doi:10.29244/HAJ.7.2.120

Authors

Gatot Prayoga 1) Coastal and Marine Resources Management Study Program, Faculty of Fisheries and Marine Sciences, IPB University, Bogor, Indonesia; 2) Department of Aquatic Resources Management, Faculty of Fisheries and Marine Sciences, IPB University, Bogor, Indonesia; 3) Center for Environmental Research, IPB University, Bogor, Indonesia https://orcid.org/0000-0002-7825-2895
Rizki Moch Rijaldi Center for Environmental Research, IPB University, Bogor, Indonesia
Rizqi Fahma Sidik Center for Environmental Research, IPB University, Bogor, Indonesia
Hefni Effendi Department of Aquatic Resources Management, Faculty of Fisheries and Marine Sciences, IPB University, Bogor, Indonesia
Gatot Yulianto Department of Aquatic Resources Management, Faculty of Fisheries and Marine Sciences, IPB University, Bogor, Indonesia

DOI:

https://doi.org/10.29244/HAJ.7.2.120

Keywords:

correlation analysis, decentralized WWTP, household connections, influent domestic wastewater, small island

Abstract

This study examined whether the number of household connections (SR) is associated with influent domestic wastewater characteristics at decentralized WWTPs on Tidung Besar Island, Indonesia. The dataset covered four service zones (North, West, East, and South) observed annually from 2022 to 2025. SR was treated as the independent variable, while pH, BOD5, COD, TSS, oil and grease, ammonia, surfactant anionic (MBAS), free chlorine, total coliform, fecal coliform, and discharge were treated as dependent variables according to data availability. Although monitoring was conducted at both WWTP inlets and outlets, this study used inlet data only to represent untreated wastewater entering the system and to avoid confounding from treatment processes. Exploratory simple linear regression and Pearson correlation were applied to pooled zone-year observations, supplemented by leave-one-out cross-validation (LOOCV) as a predictive robustness check. Total household connections increased from 729 in 2022 to 831 in 2025. Across the pooled 2022-2025 dataset, the highest positive correlations among the main parameters were observed for BOD5 (r = 0.362) and COD (r = 0.346), while pH (r = 0.061), TSS (r = -0.135), oil and grease (r = 0.216), and ammonia (r = -0.083) showed negligible relationships. Discharge showed a low positive correlation with higher value (r = 0.446) but should be interpreted cautiously because of possible flow-meter problems. Parameters introduced or discontinued after regulatory changes were treated as exploratory only. None of the pooled relationships were statistically significant (p > 0.05), and LOOCV yielded negative predicted R² values, indicating poor predictive stability. Overall, SR alone was not a reliable predictor of influent wastewater characteristics.

Downloads

Download data is not yet available.

References

Adrianto, L., Kurniawan, F., Romadhon, A., Bengen, D. G., Sjafrie, N. D. M., Damar, A., & Kleinertz, S. (2021). Assessing social-ecological system carrying capacity for urban small island tourism: The case of Tidung Islands, Jakarta Capital Province, Indonesia. Ocean & Coastal Management, 212, 105844. https://doi.org/10.1016/J.OCECOAMAN.2021.105844

Arijuddin, B. I. (2024). Water Carrying Capacity on Small Islands Tourism: Case Study of the Tidung Islands, Jakarta. Jurnal Syntax Admiration, 5(6), 2350–2358. https://doi.org/10.46799/JSA.V5I6.1214

Bugajski, P., Mucha, Z., Kois, B., Zakład, M., Agów I Kanalizacji, W. ˛, & Targu, N. (2025). The Influence of Rainwater and Snowmelt (Inflow and Infiltration) on the Performance of Wastewater Treatment in a Plant Using Membrane Bioreactors (MBR). Applied Sciences 2025, Vol. 15, Page 10608, 15(19), 10608. https://doi.org/10.3390/app151910608

Eales, K., Blackett, I., Siregar, R., & Febriani, E. (2013). Review of Community-Managed Decentralized Wastewater Treatment Systems in Indonesia. www.worldbank.org

Hayati, Y., Adrianto, L., Krisanti, M., Pranowo, W. S., & Kurniawan, F. (2020). Magnitudes and tourist perception of marine debris on small tourism island: Assessment of Tidung Island, Jakarta, Indonesia. Marine Pollution Bulletin, 158. https://doi.org/10.1016/j.marpolbul.2020.111393

Hinkle, D. E., Wiersma, W., & Jurs, S. G. (2003). Applied Statistics for the Behavioral Sciences (5th ed.). Houghton Mifflin. https://archive.org/details/appliedstatistic0000hink_o7h5/page/n7/mode/1up

James, G., Witten, D., Hastie, T., & Tibshirani, R. (2021). An Introduction to Statistical Learning: with Applications in R (2nd ed.). Springer US. https://doi.org/10.1007/978-1-0716-1418-1

Khrisnamurti, Utami, H., & Darmawan, R. (2016). THE IMPACTS OF TOURISM ACTIVITIES ON THE ENVIRONMENT IN TIDUNG ISLAND, KEPULAUAN SERIBU. http://jejakwisata.

Macura, B., Metson, G. S., McConville, J. R., & Harder, R. (2024). Recovery of plant nutrients from human excreta and domestic wastewater for reuse in agriculture: a systematic map and evidence platform. Environmental Evidence 2024 13:1, 13(1), 21-. https://doi.org/10.1186/S13750-024-00342-5

Mukaka, M. M. (2012). A guide to appropriate use of Correlation coefficient in medical research. Malawi Medical Journal : The Journal of Medical Association of Malawi, 24(3), 69. https://pmc.ncbi.nlm.nih.gov/articles/PMC3576830/

Office of Water US EPA. (1978). Method 410.3: Chemical Oxygen Demand (Titrimetric, High Level for Saline Waters) by Titration. https://www.epa.gov/sites/default/files/2015-08/documents/method_410-3_1978.pdf

Oteng-Peprah, M., Acheampong, M. A., & deVries, N. K. (2018). Greywater Characteristics, Treatment Systems, Reuse Strategies and User Perception—a Review. Water, Air, & Soil Pollution 2018 229:8, 229(8), 255-. https://doi.org/10.1007/s11270-018-3909-8

Picard, R. R., & Cook, R. D. (1984). Cross-validation of regression models. Journal of the American Statistical Association, 79(387), 575–583. https://doi.org/10.1080/01621459.1984.10478083

Prayoga, G., Yulianto, G., & Effendi, H. (2025). Assessing wastewater treatment performance in small island contexts: a multi-aspect evaluation of Tidung Besar Island, Indonesia. Jurnal Pengelolaan Lingkungan Berkelanjutan (Journal of Environmental Sustainability Management), 265–289. https://doi.org/10.36813/jplb.9.3.265-289

Regulation of the Minister of Environment and Forestry No P.68 Year 2016 on Domestic Wastewater Quality Standard (2016).

Regulation of the Minister of Environment/Environmental Management Agency No. 11 of 2025 on Wastewater Quality Standards and Wastewater Treatment Technology Standards for Domestic Wastewater (2025).

Rodríguez-Alcántara, J. S., Cruz-Pérez, N., Rodríguez-Martín, J., García-Gil, A., & Santamarta, J. C. (2024). Effect of tourist activity on wastewater quality in selected wastewater treatment plants in the Balearic Islands (Spain). Environmental Science and Pollution Research, 31(10), 15172–15185. https://doi.org/10.1007/S11356-024-32173-9/FIGURES/10

Rouse, J. D. (2015). Development of Environmentally Sustainable Methods for Treatment of Domestic Wastewater and Handling of Sewage Sludge on Yap Island. Sustainability 2015, Vol. 7, Pages 12452-12464, 7(9), 12452–12464. https://doi.org/10.3390/su70912452

Schober, P., Boer, C., & Schwarte, L. A. (2018). Correlation coefficients: Appropriate use and interpretation. Anesthesia and Analgesia, 126(5), 1763–1768. https://doi.org/10.1213/ANE.0000000000002864

Stone, M. (1974). Cross-Validatory Choice and Assessment of Statistical Predictions. Journal of the Royal Statistical Society. Series B (Methodological), 36(2), 111–147. https://sites.stat.washington.edu/courses/stat527/s13/readings/Stone1974.pdf?utm_source=chatgpt.com

Sururi, M. R., Dirgawati, M., Wiliana, W., Fadlurrohman, F., Hardika, & Widiyati, N. (2023). Performance evaluation of domestic waste water treatment system in urban Indonesia. Case Studies in Chemical and Environmental Engineering, 8(2), 100507. https://doi.org/10.1016/j.cscee.2023.100507

Watanabe, R., Harada, H., Yasui, H., Le, T. Van, & Fujii, S. (2021). Exfiltration and infiltration effect on sewage flow and quality: a case study of Hue, Vietnam. Environmental Technology (United Kingdom), 42(11), 1747–1757. https://doi.org/10.1080/09593330.2019.1680739

Widyarani, Wulan, D. R., Hamidah, U., Komarulzaman, A., Rosmalina, R. T., & Sintawardani, N. (2022). Domestic wastewater in Indonesia: generation, characteristics and treatment. Environmental Science and Pollution Research, 29(22), 32397–32414. https://doi.org/10.1007/s11356-022-19057-6

World Bank. (2013). East Asia Pasific Region Urban Sanitation Review : Indonesia Country Study. In Urban Sanitation Review : Indonesia Country Study. Washington, DC. https://doi.org/https://doi.org/10.1596/17614