Mapping of rain water harvesting potential at Keduang Sub-watershed, Central Java, Indonesia

Abstract

One of the main issues in agriculture in this climate change era is the water crisis. It caused a drought that affected the delay of rice cultivation. A study found that Wonogiri Regency has very critical with a value of 163.1%. Hence, it is necessary to have an alternative solution to overcome it. In this case, utilizing rain by harvesting rainwater (RWH) can be used as an alternative to meet water needs during the dry season and for various other uses. One of the RWH applications is a small-farm reservoir (SFR). To identify the potential locations for RWH is using location suitability modelling based on GIS. The determination of the location depends on biophysical criteria such as rainfall, slope, soil texture, stream order, and land use. The socio-economic attributes consist of the distance to the river, road, settlement, and agriculture. To obtain the suitability location, after all of the maps are generated, next is reclassify the value to 0 and 1. In the end, the maps calculate with a raster calculator to define the suitability location that has value 1. Location and dimension details can find out. This study aims to determine the potential of RWH for agriculture (in specific, SFR) at Keduang Sub-watershed as a consideration for stakeholders’ decision. The results showed 226 areas are potential for SFR implementation and will make it easier for stakeholders to decide by comparing the suitability location map and the long-term strategic map.