Air pollution and surface water contamination are closely interconnected environmental issues that pose significant risks to ecosystems and human health. This chapter explores the pathways through which air pollutants contribute to surface water contamination, focusing on both natural and anthropogenic sources. Key pollutants, including particulate matter (PM2.5, PM10), nitrogen oxides (NO3), sulphur dioxide (SO2), volatile organic compounds (VOCs), and heavy metals like lead and mercury, are examined for their roles in degrading water quality. These contaminants enter water bodies through wet and dry atmospheric deposition, affecting water chemistry by altering parameters such as pH, turbidity, dissolved oxygen (DO), and chemical oxygen demand (COD). The chapter further delves into the chemical transformations occurring in water, such as acid rain and eutrophication, resulting from airborne pollutants. The ecological impacts on aquatic biodiversity, bioaccumulation of toxins in the food chain, and long-term disruptions to aquatic ecosystems are discussed, alongside the human health risks posed by drinking water contamination and the use of polluted water in agriculture. Through real-world case studies and policy analysis, the chapter highlights the need for integrated air and water pollution management strategies. Solutions include air quality regulations, emission control technologies, and bioremediation approaches like the Root Zone process. Finally, the chapter identifies emerging research areas, such as the impact of microplastics and climate change on air-to-water pollution dynamics, emphasising the importance of continued advancements in monitoring and mitigation efforts.