Urban water supply in smart cities faces complex and interrelated challenges that arise from rapid urbanization, technological integration, environmental pressures, and governance constraints. One of the primary issues is the growing demand-supply gap. Increasing population, migration, and expanding urban boundaries exert immense pressure on existing water resources, often leading to over-extraction of groundwater and depletion of natural sources. Many cities struggle to ensure equitable distribution, resulting in disparities where some areas receive continuous supply while others face acute shortages. Aging and inadequate infrastructure is another significant concern. Many urban water systems are characterized by old pipelines, leakages, and inefficient distribution networks, causing substantial non-revenue water losses. Even in smart cities where digital technologies are introduced, integrating them with outdated physical infrastructure becomes difficult and costly. Frequent pipe bursts, contamination risks, and maintenance challenges reduce system reliability and increase operational costs. Water quality and contamination present serious issues. Urban water sources are often polluted by industrial discharge, untreated sewage, and solid waste. Inadequate wastewater treatment facilities further exacerbate the problem, leading to health risks and environmental degradation. Ensuring safe drinking water requires continuous monitoring, advanced treatment technologies, and strict regulatory enforcement,