The world of membrane separation processes and nanotechnology are in the avenues of new scientific regeneration and divinity. There are serious environmental engineering concerns in the global scenario. Excessive industrialization and rampant economic growth are threatening the global scientific and social fabric. Thus the need of conventional and non-conventional environmental engineering tools. In this treatise we discuss the rapid advances in the field of membrane separation processes and nanotechnology in the field of treatment of surface water and groundwater. The other areas of research endeavor are the application of membrane filtration and nanotechnology in arsenic and heavy metal groundwater remediation. This is a burning and vexing problem in many developing and developed nations around the globe. Thus the need of a deep scientific introspection and vast scientific and engineering vision in drinking water and industrial wastewater treatment.