Based on the National River Basin Classification map, Indonesia has a total of 42,210 river basins organized as a basis for determining watershed management policies. The policy decisions are based on various criteria such as land conditions (critical land, land cover, erosion), water quality, water quantity, water continuity, socio-economic factors, investment in soil and water conservation structures, as well as spatial utilization.[1]
In the National Medium-Term Development Plan (RPJMN) for the period 2015–2019, there were 15 priority river basins (indicated in yellow) out of 108 designated priority river basins in the Integrated River Basin Management Plan (RPDAST) according to Decree No. 328/Menhut-II/2009. Additionally, there are 9 river basins categorized as disaster-prone areas. Going forward, all the 108 designated priority river basins in the RPDAST will be given priority, particularly for the implementation of soil and water conservation activities during the 2020-2024 period.[2]
Codification
The River Basin Codification is a code that has been structured in such a way that each digit has a unique meaning that can distinguish two or more river basins with the same name. The codification of each river basin is created using 9 (nine) digits.[3]
The first three digits (in blue) represent the thematic classification of the data, which is the river basin (DAS). This is to help users easily identify that the theme refers to river basins.
The fourth digit (in purple) represents the region of the River Basin (where the River Basin is located). The region codes start from the western part of the island, in the following order:
The fifth digit (in yellow) represents the inter-basins (coverage of river basin in one or more administrative regions). The reference administrative map used is the Bakosurtanal (Geospatial Information Agency) administrative map, with the following order:
Within one Regency/City = 1
Across Regencies/Cities = 2
Across Provinces = 3
Across Countries = 4
The last four digits (in green) represent the serial number of the river basin. The numbering of river basins follows the map index boxes of the 1:250,000 scale map, starting from the western part of the main island (the largest island), followed by smaller surrounding islands from the west.
Example, the Citarum basin has a code "DAS220047". The code indicates the Citarum Basin is located in the Java region, it is an inter-regency/city river basin and it is the 47th serial number in the Java region.
Basin list
Here are several river basins in Indonesia, especially those located on the major islands:[3][4][5]
