The purpose of this study was to determine the quality of drinking water that is suitable for drinking based on the pH value and TDS content and to provide information on the water level map in Siduarjo Regency. This research is descriptive quantitative research of experimental analysis. The stages of the research included making instrument calibration instruments as well as collecting and analyzing field data which included 14 water sampling points. Based on the reference value for drinking water quality (<500ppm) and tolerance for appropriate use (<1000ppm) 1 sample point of water is classified as suitable for drinking with a TDS value of <500ppm which is in the calm zone. Whereas TDS 13 points above >500ppm but still <1000ppm so it can still be used in household activities but if eaten it needs to go through a cooking process to remove heavy metals or substances in the water. The pH of the water from 14 points is not extreme outside the normal pH range of 6 – 9,5. The lowest water pH is 6,97 in the Siduarjo city area and the highest is 7,79 in the Tariq area. The main thing is that the TDS and pH in the Situarjo area are evenly distributed because of the flow of the river so that if one area is polluted it will affect the water quality in other areas either TDS or TDS and pH.