Why water reuse in agriculture makes sense today
Wastewater reuse in agriculture is becoming a practical lever for making the agri-industrial supply chain more resilient, especially where water is an increasing cost and availability is inconsistent. The idea is simple: treat wastewater to a quality level suitable for irrigation use and reuse it in a controlled way, reducing withdrawals from primary sources and stabilizing supply during critical periods. In this article, we look at the key steps in the process: the fit-for-purpose approach, the European regulatory framework and risk management, industrial polishing technologies, and the most common applications in the agri-industrial sector. At IDRO Group, we support farms, livestock businesses and agri-industrial operations with water treatment and recovery solutions, integrating plant engineering with safety, monitoring and operational management criteria.
Reusing wastewater in agriculture: what fit-for-purpose really means
When talking about wastewater reuse in agriculture, the key question is not just “can I reuse it?” but “for which crop, with which irrigation method, and with what guarantees?” Effective reuse is always fit-for-purpose, meaning tailored to the actual use: drip or sprinkler irrigation, crops intended for raw consumption or processing, seasonality, soil type, and the distance between treatment and the field. In practice, this means defining a target quality consistent with the intended use, taking into account not only microbiological parameters, but also agronomic and operational factors such as salinity and sodicity, nutrient load, fine solids and clogging risk (especially in drip lines), as well as any micropollutants related to the wastewater matrix. This approach reduces complexity and costs because it avoids pursuing potable-water quality where it is unnecessary, while at the same time requiring properly designed barriers and controls, as well as correct management of storage and distribution, in order to maintain stable performance and prevent hygienic-sanitary and agronomic risks.
Regulations and requirements: the EU Regulation on wastewater reuse in agriculture and risk management
The European regulatory framework for wastewater reuse in agriculture for irrigation purposes is linked to the minimum requirements introduced by Regulation (EU) 2020/741, which strengthens the concept of risk management throughout the entire chain, from treatment to final use in the field. In practice, beyond quality parameters and monitoring, it becomes essential to demonstrate that the entire system is designed and managed to reduce risks in a way that is proportionate to the intended use.
At the international level, similar principles are also reflected in technical references such as the WHO Guidelines on the safe reuse of wastewater, as well as operational resources adopted in different countries, such as those promoted by the US EPA for agricultural water reuse, which emphasize the combination of treatment, controls and good practices in the field.
At national and local level, permits, requirements and controls must then be contextualized according to the receiving environment, the type of plant and the irrigation project, which is why a preliminary technical and regulatory analysis is an integral part of the process.
Industrial technologies for wastewater reuse in agriculture: from treatment to polishing
To enable wastewater reuse in agriculture on a stable basis, the treatment line must handle the variability and peaks typical of the agri-industrial sector and guarantee repeatable water quality over time. In practice, the process is built in stages: pre-treatment and equalization for stabilization, biological or physicochemical treatment depending on the matrix, and final polishing to make the water compatible with irrigation and the dedicated distribution network. It should also be made clear that not all wastewater is automatically suitable for irrigation reuse: feasibility depends on the matrix, load variability and the required target quality, all of which determine the necessary polishing train.
In reuse-oriented projects, polishing is often the factor that makes the real difference: more advanced filtration, membranes where needed, and disinfection consistent with the level of risk and the intended application. For operational safety, it is essential to provide a dedicated non-potable water network, clearly identified and physically separated from potable water, with suitable protection against backflow and improper connections. At IDRO Group, we offer systems for the recovery and reuse of wastewater with modular and integrable solutions downstream of treatment, designed for non-potable uses such as irrigation and washing, with control logic that supports continuity and traceability.
Practical applications in the agri-industrial sector and impacts on costs and sustainability
In the agri-industrial context, water reuse is particularly effective when there is both a steady production of treatable wastewater and a significant irrigation demand. The most common applications include:
- Controlled irrigation and fertigation (where compatible): reuse of polished water to reduce withdrawals from wells or the grid and improve continuity of supply.
- Supporting non-potable uses on farms or in agri-industrial facilities, such as technical washing and plant services, where the required quality is defined by the use and by internal procedures.
The benefits can be measured on three levels: reduced volumes of purchased or abstracted primary water, greater production stability during periods of scarcity, and an improved environmental footprint thanks to the reduction in total water withdrawal.
At the same time, irrigation efficiency remains essential: strategies such as micro-irrigation, drip irrigation and management based on actual crop demand increase the effectiveness of reuse and reduce waste.
How we approach an agricultural wastewater reuse project: from assessment to plant management
A wastewater reuse project in agriculture works when treatment, the distribution network and agronomic use are conceived as a single system. We generally start with characterization of the matrix and the water balance, define compatible uses and the target quality, then design the treatment train and the controls, including sampling points and safety logic (alarms, diversion to discharge, management of non-conformities). As a final step, we also define a management and maintenance plan proportionate to the intended use: periodic checks, verification of disinfection effectiveness, filter cleaning/replacement, management of any storage volumes, and traceability of parameters, so as to maintain performance over time and support compliance. The goal is to make reuse practical in day-to-day management as well, without increasing complexity beyond what is necessary.
If you want to evaluate a wastewater reuse system in agriculture for your company or for an agri-industrial facility, IDRO Group can support you from design to turnkey implementation all the way through operational management, with solutions consistent with the applicable regulations and the required control standards, in line with the needs of the irrigation project and the site.
Contact IDRO Group for more information!
