Use of Reclaimed Wastewater in Agriculture: Literature Review

Abstract

Due to the rapid development of urban and rural domestic water supplies, conventional water resources have been seriously depleted and reclaimed wastewater (RWW) use for irrigation, among other non-conventional water sources, has gained an increasing role in the planning and development of additional water supplies. This literature review elaborates the benefits and risks associated with RWW as a non-conventional water resource with an emphasis on research carried out in the Middle East and North Africa (MENA) region.

The use of RWW for agricultural irrigation is often viewed as a positive means of recycling water due to the potentially large volumes of water that can be made available. RWW has the advantage of being a constant, reliable water source and reduces the amount of fresh water extracted from the environment.

There remain concerns about the quality of the RWW and its potential negative impact on both crops themselves and on the end users of the crops. Water quality issues that can create perceived problems in agriculture include nutrient and sodium concentrations, heavy metals, and the presence of contaminants such as human and animal pathogens, all of which can be safely managed. The risks associated with using RWW are not the same in all countries due to many reasons: different RWW properties and its management, soil profiles, crop diversity and management, and climate, to name a few.

The review uses scientific and technical works to show that RWW can be a valuable and safe resource for crop irrigation that poses minimal risk to the soil, groundwater and crops, and is a key factor towards food security.

The main conclusions issued from this RWW literature review are the following: • The use of RWW in agriculture can act as a non-conventional water source and contribute to food security. • Establishment of appropriate national policy framework, addressing specific or local needs, for the use of RWW is necessary. • Continuous and sustainable monitoring programs or systems for ensuring public safety and protecting the environment are necessary. • More long-term impacts research on the using of RWW for growing perennial crops as well as its impacts on the animals health and production is important. • Extensive capacity building and training necessary (for National staff and farmers) as well as an increase in public awareness on the safe use of RWW in agriculture. • Public awareness on the safe use of RWW in agriculture must be raised as social acceptance remains a significant barrier to full practice roll-out.