Floods are disasters that often occur in several parts of Indonesia. Almost every area that has a low altitude must have experienced flooding, one of which is Samarinda City. Flooding in Samarinda City is common and frequent. The use of SRTM images as material for analyzing natural resources and natural disasters, where data collection does not require direct contact with the objects studied is very effective and efficient in terms of time, cost and human labor. The purpose of this study was to create a surface flow map in Samarinda City with Shuttle Radar Topography Mission (SRTM) satellite image. Knowing terrain of catchment area in Samarinda City. The research method used is analysis of Surface Flow Forecast using Shuttle Radar Topography Mission (SRTM) Satellite image and carrying out the process of making surface flow forecasts for Samarinda City using Arc GIS 10.3 software. Data processing is carried out using Arc ToolBox as a tool in Arc GIS 10.3 software by creating water flow and catchment area with downloaded SRTM satellite image. The results of study can provide information about the waterway and the area of the accompanying catchment area in Samarinda City as a consideration of Samarinda City government's policy in flood management. The results showed that most of Samarinda area is in the Karang Mumus sub-watershed so that catchment area shown through data processing on application used gives very broad results, which is as wide as 46,699.44 Ha. Areas outside of Karang Mumus sub-watershed area gave the result that, the area of water catchment in Samarinda Utara district is 6,258.73 Ha, Samarinda Ulu 24.55 Ha, Sambutan 4,046.87 Ha, Sungai Kunjang 438.76 Ha, Loa Janan Hilir 61.35 Ha, Palaran 10,536.40 Ha. Six sub-districts, namely Sungai Pinang, Samarinda Seberang, Samarinda Kota and Samarinda Ilir are sub-districts located entirely in the Karang Mumus sub-watershed area.

Keywords : Shuttle Radar Topography Mission (SRTM), water flow estimation, remote sensing.