This design aims to contrive a plumbing system X Apartment, Jakarta with a separate clean water and drinking water system. Water supply system that applied to this apartment is roof tank system. Fluctuations in the use of clean water are used to determine the capacity of reservoirs and pumps using the equivalent apartments such as The Bellagio Residence Apartment, Four Winds Apartment, Tamansari Sudirman Apartment, and Setiabudi Residence Apartment. Total demand for clean water for the 1st and 2nd tower is 315.8 m3/day and 39 m3/day for drinking water with 216 m3 of ground water tank capacity. Transfer pumps work for 12 hour/day and the capacity of clean water roof tank for the 1st and 2nd tower are 67.5 m3 while for drinking water roof tank are 7.2 m3. System that has been chosen used 2 stand pipes for both clean water, drinking water, and booster pumps in each tower. This design concluded that The investment cost of clean water and drinking water system and also the construction of X Apartment reservoirs is Rp. 2.393.889.860 and the cost of drinking water that can be saved by residents when using drinkable tap water system is Rp. 874.656 per m3.