Towards safe, sustainable irrigation using effluent from wastewater treatment plants (WWTPs)

Research into water treatment systems is being carried out to find out how effluent from wastewater treatment plants (WWTPs) could be used for irrigation in agriculture. The research is primarily focused on understanding the risks of spreading contaminants to fruits and vegetables, the health risks associated with this, and the types of water treatment and monitoring that would be required to prevent this.

The objective of the project is to increase the availability of high-quality irrigation water for irrigation and horticulture during dry periods, and to prevent the damaging impact of excessive groundwater harvesting on agricultural crops and the natural environment. Effluent from wastewater treatment can be made suitable for irrigation as an alternative to groundwater. This is particularly important during times of drought, as a way of supplementing limited supplies of groundwater and reducing damage to crops while continuing to ensure food safety.

Food safety

The quality of the irrigation water derived from effluent is an important factor in this, particularly in terms of food safety. This project will look to which extent contaminants from effluent end up in and on crops (fruits and vegetables), the health risks associated with this, and the measures (water treatment, monitoring) that are required to minimise these risks.

On 25 May 2020, European regulations came into effect to stipulate minimum quality standards for recycled water destined for agricultural purposes. In the event of any suspicion that such water might contain components that could affect public health, an additional risk assessment is required.

Through this project, Wageningen Food & Biobased Research hopes to contribute to the expansion of water recycling and to combating the effects of drought, and to develop practical tools for these risk assessments. The consortium is made up of knowledge institutes, water boards, agricultural sector organisations and technology suppliers.