This research aims to determine the potency of roof top rainwater harvesting volume and to determine its quality of rainwater in LempakeVillage, Samarinda City, for domestic needs in the next decade (2014-2024). The results showed that 659,902.43 m2 catchment area of rooftop rainwater utilization could harvest 1,198,419.76 m 3 rainwater per year to fulfill the domestic needs in 2014. This was the potency of rainwater harvested for the next decade (2014 2024) with an estimated population number of 22,437 and the domestic needs of 982,749.21 m 3 of water per year. Laboratory test showed has revealed a low hardness value of 19.37 mg/l (soft water), which is good for domestic activities,especially for bathing, washing, and sanitation. In addition, the quality of rainwater meet the quality standards of East Kalimantan Regional Regulation N o. 02 of 2011 and Government Regulation No. 82 of 2001
Rainwater harvesting, ArcGIS
