Water is essential to every living being. Water management and resource conservation is very important to provide safe and clean water to all. Resources of water have been polluted and contaminated due to increasing population and urbanization. Irrigation and hydropower reservoir are other sources responsible for water stress on earth. The main aim of smart cities and urban development is to provide clean and safe water for everyone at low cost and in sustainable ways. Thus, it is necessary to conserve water resources and manage the water smartly. Use of non-conventional water resources for irrigation, aquaculture and aquifer recharge is one of the smart solutions to decrease the use of fresh water resources for these purposes. Machine learning is the smart solution for managing and conserving the water resources. Various machine learning models is applied for prediction tasks. However, deep learning is applied for categorization and regression task. The chapter objective is to provide the smart and sustainable solution for managing water resources and conservation in smart cities.