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Raw water need increases along with the development of a region. In terms of quantity and quality, surface water tends to decrease due to several factors, such as land use changes and pollution, which causes an increase in the exploitation of groundwater to meet the raw water needs of the community. The Tondano watershed is one of the priority watersheds that acts as the center of economic development in North Sulawesi Province. Cities in the Tondano watershed area are developing rapidly, thereby increasing the need for water for domestic use, especially groundwater, which is of better quality and easier to obtain. For groundwater in the Tondano watershed to be sustainable and meet the required quality standards, it is necessary to know about groundwater recharge and the groundwater quality to be suitable for use. This study aims to estimate groundwater recharge based on simple groundwater balance and assess groundwater quality based on Physico-chemical properties. The method used in this study is to estimate groundwater recharge by calculating groundwater balance using data on annual rainfall, annual evapotranspiration, and annual runoff. Meanwhile, for groundwater quality, physical and chemical properties were measured, including pH, Total Dissolve Solid (TDS), Electrical Conductivity (EC), and temperature at 21 measurement points, including springs, dug wells, and drilled wells. The parameters measured in the field are then compared with the World Health Organization (WHO) standard and the Ministry of Health standard to determine their quality and suitability for usage. The results indicate that the calculation of groundwater recharge shows a positive value. The measurement of Physico-chemical parameters in the field suggests that the pH value is in the range of 6.1-7.9, the TDS range is 50-200 mg/L, the EC range is 110-400 µs/cm, and the temperature range is 23.4-35.6 °C. Based on the analysis using WHO standards and the Ministry of Health standards, it shows that the quality of the groundwater is suitable for use.