Handbook of Environmental Engineering

13Wastewater Recycling

Judith L. Sims¹ and Kirsten M. Sims²

¹ Utah Water Research Laboratory, Utah State University, Logan, UT, USA

² WesTech Engineering, Inc., Salt Lake City, UT, USA

13.1 Introduction

Clean water is essential to the development of nations; however, according to a 2006 United Nations report, over one billion people have no access to clean water, and 2.6 billion people lack access to adequate sanitation (UNDP, 2006). To provide this access, existing water resources must be used more efficiently, and new sources of freshwater need to be found, especially in urban areas where most of the world’s population now lives. New sources are essential for the world’s population due to:

• Population growth.
• Contamination and deterioration of surface and groundwaters.
• Uneven distribution of water resources throughout the world.
• Frequent droughts.

Desalination of ocean water, brackish groundwater, and other salty water sources is one potential new source of water. Desalination is usually used in areas without an adequate supply of water, as it is an expensive and energy‐intensive process.

Reclaiming and reusing wastewater is another source of additional clean water, especially as large amounts of wastewater are generated near urban population centers. The terms “reclaimed water” and “recycled water” are both commonly used to refer to water that, as a result of wastewater treatment, is suitable for a direct beneficial or controlled use. De facto reuse has been practiced for ...