Southeast Asia is vulnerable to climate change with over half of its population already being impacted by drought, flooding, and rise in sea levels recently. This work reviews the current water resource challenges in Indonesia, prone to the rising impacts of climate change. A baseline assessment of Indonesia's water and drinking water resources related to its original sources is presented. In response to a growing concern over chronic challenges that undermine water supply nationwide, this study analyses drinking water safety supervision. To accomplish this, a literature survey (100 studies published during the 2000–2023 period) was performed to identify regional groundwater resources sustainability and water security issues. Among the main findings of this study, only 10% of rainfall infiltrates to the groundwater, while 70% of its rivers are heavily polluted by domestic waste. During the study period, water availability decreased to 1,200 m3/year in 2020, with only 35% of the resources being economically feasible for reuse. The water supply deficit in Indonesia was estimated to be 5.5 hm3/year with roughly 67% of the population's water demand satisfied in 2021. Although this deficit might be fulfilled with private vendors, water supply/demand forecasts in 2030 suggest that the gap could not be closed by increasing water supply.