Water balance analysis of Talau-Loes Watershed, a cross border watershed of Indonesia and East Timor




Abstract. Riwu-Kaho M, Mella WII, Mau YS, Riwu-Kaho NPLB, Nur MSM. 2020. Water balance analysis of Talau-Loes Watershed, a cross border watershed of Indonesia and East Timor. Trop Drylands 21: 17-24. The Talau-Loes watershed is a cross-border watershed in Indonesia and Timor Leste (East Timor) which has traditionally been a natural resource for living, cultivation and conservation areas for communities in several districts of Belu Regency, Indonesia, and several areas in the Timor Leste territory. Water shortages in the land system are thought to play a significant role in the low productivity of agricultural crops. This study aimed to predict water balance in the Talau watershed, and to estimate river discharge in Malibaka Sub-watershed of Talau-Loes watershed. The study results showed that the amount of annual precipitation of 1679 mm was smaller than the total amount of water lost, amounting to 1914.79 mm per year, originating from evapotranspiration (ET) of 1650.91 mm and runoff water of 263.85 mm. Thus, theoretically, there would be an annual deficit of 235.79 mm in the Talau watershed. However, at the peak of the groundwater deficit, it turned out that the Malibaka River in the Malibaka sub-watershed and the Talau watershed had a discharge of 18 mm3/sec. This gives a clue about the ability of the groundwater level to gradually release its water reservoir as a source of base flow. Soil and water conservation actions that combine integrated systems such as agroforestry systems with mechanical conservation actions are proposed as solutions that need to be studied and developed in the future.



Dianitasari R, Purnama S. 2017. Analysis of Hydrometeorological Water Balance with Approach of Physical Characteristics of the Das in the Gondang Watershed, Nganjuk Regency, East Java Province. Jurnal Bumi Indonesia 6 (1). 2017.
McCabe GJ, Markstrom SL. 2007. A monthly water-balance model driven by a graphical user interface: U.S. Geological Survey Open-File report 2007-1088.
Hartanto P. 2017. Calculation of Cidanau Watershed Using the Thornhwaite Method. Journal of Geological and Mining Research Vol. 27, No. 2, December 2017: 213-225.
Kendall C, McDonnell JJ (Eds.). 1998. Isotope Tracers in Catchment Hydrology. Elsevier, Amsterdam.
Newhall F, Berdanier CR. 1996. Calculation of soil moisture regimes from the climatic record. Soil Survey Investigations Report No. 46, National Soil Survey Center, Natural Resources Conservation Service, Lincoln, NE.
Purnama IgLS, Trijuni S, Hanafi F, Aulia T, Razali R. 2012. Water Balance Analysis in the Kupang and Sengkarang Watersheds. MPPDAS - Faculty of Geography, Gadjah Mada University. Yogyakarta.
Riwu Kaho LM. 2015a. Watersheds and how to manage them. Undana Research Institute Publisher, Kupang.
Riwu Kaho LM. 2015b. Rapid Survaey Performance of Talau, Belu, NTT Watershed (RI-RDTL Cross-border Watershed).
Sebhat MY. 2014. Water balance of the Juba and Shabelle Rivers in Ethiopia-Somalia, International Research Journal of Agricultural Science and Soil Science 4 (4): 65-75, DOI: 10.14303 / irjas.2014.027.
Thornthwaite CW, Mather JR. 1997. Instruction and Tables for Computing Potential Evapotranspiration and Water Balance. Publication in Climatology, Drexel Institute of Technology, Laboratory of Climatology Vol. X No. 3. New Jersey.