Water sources around the world are increasingly contaminated by heavy metals (HM), synthetic dyes, and other toxic pollutants released primarily by industrial factories rather than household waste. This widespread pollution demands robust monitoring systems to protect natural water bodies. Among the various wastewater treatment methods available, the use of two-dimensional (2D) materials has emerged as a highly promising solution due to their unique structural properties and exceptional characteristics, which significantly enhance contaminant removal efficiency. These emerging 2D materials, such as graphene, graphene oxide, g-C3N4, transition metal dichalcogenides (TMDs), boron carbon nitride, MXenes, metal-organic frameworks, and black phosphorus, possess unprecedented surface-to-volume ratios, allowing for minimal material consumption, rapid processing, and high treatment efficiency in water purification and monitoring. These materials are widely applied in several wastewater treatment technologies, including adsorption, filtration, photocatalysis, and electrochemical processes. TMDs and MXenes offer diverse applications in water and effluent treatment because of their unique properties and broad applicability. This review explores the potential of these materials in water remediation and wastewater treatment while also discussing novel research directions. Additionally, the chapter concludes by highlighting the growing role of 2D materials in advancing the water purification industry, with a focus on their future applications.