Comparison of water availability in 2015 and 2022 based on land cover in the Maros River Basin

Forest as one of permanent vegetation can have an impact either to increase or decrease the quality of a watershed due to the changes in land cover. Land use activities that are changing landscapes within a watershed can often affect water yield. This study aims to determine the availability of water in Maros watershed in 2015 and 2022 and to identify the sub-watershed experiencing changes in water availability. Data analysis in this study uses the SWAT (Soil and Water Assessment Tool) model. Input data used in the analysis are the 2015 land use map, 2022 land cover projected map (Markov model analysis), soil type map, and Digital Elevation Model (DEM) data. The results showed that land cover in 2015 and 2022 was projected to change. The number of settlement and rice fields area was increased, while the forest vegetation was decreased. The change in land cover will affect water availability. The result of the SWAT modeling analysis showed that the availability of water in Maros Watershed in 2015 was 1,303,169,370 m³, and in 2022 was 1,322,495,380 m³. The volume of water availability from 2015 to 2022 has increased by 19,326,010 m³. The increase that occurred was influenced by the surface flow, which increased from 2015 to 2022. There are 38 sub-watershed, which have decreased water availability, 26 sub-watersheds in which the water availability was increased while one sub-watershed did not change at all.