Comparison of the NRECA and FJ Mock Methods for Raw Water Availability on a Very Small Island, Karimunjawa

Main Article Content

Nurul Azka Azkiya
Hartono
Siti Muawanah Robial

Abstract

Karimunjawa Island, as one of the very small islands in Indonesia, faces serious challenges in meeting raw water needs due to limited surface water resources and high evaporation rates. Evaluating water availability is essential to support the needs of the local population and the tourism sector. This study aims to compare two methods of estimating raw water availability, namely the NRECA and FJ Mock methods, using data on rainfall, climatology, hydrology, geography, topography, population, vegetation, evapotranspiration, and infiltration. The analysis results show that the NRECA method produces a maximum discharge of 0.726 m³/s in January and a minimum discharge of 0.000 m³/s in August. Meanwhile, the FJ Mock method yields a maximum discharge of 0.927 m³/s in December and a minimum discharge of 0.004 m³/s in August. In addition to the analysis results, this journal also presents sample calculations using both methods. Based on the findings, the NRECA method is considered more suitable for application in small island areas with limited data and complex hydrogeological conditions.

Article Details

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1.
Azkiya NA, Hartono H, Robial SM. Comparison of the NRECA and FJ Mock Methods for Raw Water Availability on a Very Small Island, Karimunjawa. telsinas [Internet]. 2025Sep.9 [cited 2025Sep.13];8(2):166-80. Available from: https://journal.undiknas.ac.id/index.php/teknik/article/view/6829
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References

L. Alby and E. Suhartanto, “Comparison of Rainfall-Runoff Conversion Methods Using FJ. Mock and NRECA in Kemuning Watershed, Sampang Regency,” J. Hydraulic Eng., pp. 1–8, 2018.

Jepara Regency BPS, Karimunjawa in Figures 2020, 2020. [Online]. Available: https://jeparakab.bps.go.id/publication/download

P. Hartanto and I. Hadi, “Water Availability Analysis Using the Mock Method,” J. Technology Academia ISTA, 2007.

L. P. Koestoro, “Karimunjawa and Cultural Relics of the Communities on the Northern Java Islands,” Archaeol. Bull., vol. 17, no. 1, pp. 37–51, 1997, doi: 10.30883/jba.v17i1.760.

I. R. Madyaningrum, A. C. C. Utomo, and Y. W. Pratama, “Local Community Participation in Tourism Development in Karimunjawa National Park,” Kritis, vol. 28, no. 2, pp. 140–148, 2019, doi: 10.24246/kritis.v28i2p140-148.

I. Muhardiono and D. Arthamefia, “Analysis of Irrigation Land Potential Based on Water Balance of Kembangan Reservoir,” J. Water Resour., vol. 20, no. 1, pp. 51–60, 2024, doi: 10.32679/jsda.v20i1.891.

B. W. Mutaqin et al., “Geomorphology and Oceanography Analysis for Small Island Typology Identification: Case Study in North Maluku and Karimunjawa Archipelagos,” J. Geogr. Educ., vol. 9, no. 1, 2022, doi: 10.20527/jpg.v9i1.12459.

A. Noor, A. Ramadhan, N. Asniar, N. Arsy, and E. Amalia, “Analysis of Reliable Discharge Determination Using Hydrologiska Byrans Vattenbalansavdelning Method at Paturman Dam,” JITSi, n.d.

D. Oleh, P. Fazillah, and F. Science and Technology, “Analysis of Water Availability Potential for Domestic Needs in Krueng Aceh Watershed Using Thornthwaite Mather Method,” Final Project, n.d.

A. S. Putri, E. Suhartanto, and J. S. Fidari, “Comparison of Rainfall-Runoff Conversion Methods Using FJ. Mock and NRECA in Rejoso Watershed, Pasuruan Regency,” J. Water Resour. Eng., vol. 3, no. 2, pp. 78–92, 2023, doi: 10.21776/ub.jtresda.2023.003.002.07.

M. Ramdhan, D. G. Priyambodo, et al., “Study on Surface Water Resources Utilization in Karimunjawa and Kemujan Islands,” National Seminar, Apr. 2021. [Online]. Available: http://conference.unsri.ac.id/index.php/semnashas/article/view/2056

H. I. Ratnawati, D. Purbani, M. H. Jayawiguna, and P. Karimunjawa, “Groundwater Balance Estimation on Karimunjawa Island Influenced by Hydro-Meteorological Conditions,” pp. 181–194, 2023.

D. H. Santoso, J. D. Prasetya, and D. Rahman, “Environmental Carrying Capacity Analysis Based on Ecosystem Services of Clean Water Supply on Karimunjawa Island,” J. Environ. Sci., vol. 18, no. 2, pp. 290–298, 2020.

K. W. Widyaningsih, D. Daysuseno, W. Soetopo, and J. Mayjen Haryono, “Comparison of FJ. Mock and NRECA Methods for Rainfall-Runoff Transformation in Metro Watershed, Malang Regency,” J. Water Resour. Eng., vol. 1, no. 1, 2021. [Online]. Available: https://jtresda.ub.ac.id/

G. L. Wungo, Mussadun, and S. Ma’rif, “Education on Ecotourism Concept Implementation in Karimunjawa Archipelago,” J. Pasopati, vol. 2, no. 3, pp. 142–149, 2020.

PDAM Pintar, “Clean Water Availability: Challenges and Solutions,” 2021. [Online]. Available: https://pdampintar.id/blog/lainnya/ketersedian-air-bersih/

DetikEdu, “Rainfall: Definition, Measurement Tools, and Types,” Detik.com, 2024. [Online]. Available: https://www.detik.com/edu/detikpedia/d-7243784/curah-hujan-pengertian-alat-ukur-dan-jenis-jenisnya

R. Muharomah and D. D. A. Putranto, “Runoff Analysis as an Impact of Land Use Change Around Underpass Patal Palembang Construction Using GIS Techniques,” Thesis, Sriwijaya University, 2014.

C. J. Tiwery and Y. A. Tani, “Analysis of Factors Causing Water Runoff in Drainage Channels in Leksula Village, South Buru Regency, Using EPA SWMM Program,” J. Manumata, vol. 8, no. 2, pp. 106–111, 2022.

E. G. Febrian, R. Saputri, and D. F. Saves, “NRECA Method Analysis of Reliable Discharge for Irrigation Needs and Bagong Reservoir Water Balance, Trenggalek,” Sondir: J. Civil Eng., vol. 7, no. 1, pp. 50–61, 2023. [Online]. Available: https://ejournal.itn.ac.id/index.php/sondir