Water Reuse Regulation and LIFE PureAgroH2O contribution to the pesticide residue policy agenda

In the European Union, wastewater treatment is regulated by the Council Directive 91/271/EEC of 21 May 1991, governing urban wastewater treatment (the Urban Waste Water Treatment (UWWT) Directive). The transposition of this Directive into Spanish Law is contained in the Royal Decree-Law 11/1995, of December 28, by which the standards applicable to the treatment of urban wastewater were established. Under the Greek policy, this same directive is quoted in the Joint Ministerial Decision  5673/400/1997 (B 192) “Measures and Terms for the Treatment of Urban Wastewater” amended to include ‘’List of sensitive areas’’. Complying to the UWWT directive, the parameters to be regulated and the maximum limits allowed mainly referred to microbiological and physicochemical parameters, i.e., Biochemical Oxygen Demand (BOD5), Chemical Oxygen Demand (COD), Total Suspended Solids (TSS), Turbidity and nutrient levels (nitrogen and phosphorus). No limits are established for organic synthetic chemicals.

The UWWT directive is currently under revision and update, and for the first time requirements are expected for organic microcontaminants. The focus is put on the percentage of OMC removal that might be required in the future, with the Swiss requirements as main reference (80% of selected OMC removal from the influent to the tertiary effluent). Substances such as Amisulpride, Carbamazepine, Citalopram, Clarithromycin, Diclofenac, Hydrochlorothiazide, Metoprolol, Venlafaxine, Benzotriazol or Candesartan are proposed as a reference.

With regard to the reclaimed wastewater intended for water reuse, several European countries have been actively exploring water reuse practices and implementing regulations to support them. Spain was a pioneer with the publication on 2007 of the Royal Decree 1620/2007, which established the legal framework for the reuse of treated wastewater in Spain. This RD specifies the requirements and conditions for the safe and controlled use of reclaimed water in various sectors, including agriculture, industrial processes, and urban uses. The legal framework in Greece was set under the Joint Ministerial Decision  145116/2011: “Definition of measures, conditions and procedures for the reuse of treated liquid waste and other provisions’’.

In order to harmonize regulations relating to water reuse in Europe, the Regulation (EU) 2020/741 of the European Parliament and of the Council on minimum requirements for water reuse (the Water Reuse Regulation) was published on 25 May 2020. The WRR, applicable from 26 June 2023, sets uniform minimum water quality requirements to ensure the safe reuse of treated urban wastewater in agricultural irrigation. Guidelines to support the application of Regulation 2020/741 sets out the policy report associated to the potential presence of pathogens and physicochemical parameters (BOD5, COD, turbidity Total Suspended Solids). Under this Regulation, the Urban Waste Water Treatment Directive, must undergo further treatment to meet the new minimum quality parameters for safe reuse. However, under the UWWT directive, the presence of organic microcontaminants are not yet within the policy agenda. They are only broadly referred to in the risk management section of 2020/741 regulation, as pesticides, disinfection by-products, pharmaceuticals and other substances of emerging concern, including micro pollutants and microplastics and anti-microbial resistance, but yet without limits.

To ensure a wider use of treated wastewater within an integrated water reuse management at the EU level, the concern under the environmental risks, and a lack of confidence in the health and environmental safety of water reuse practices needs to be overcome.

Under the frame of the Circular Economy Action Plan, adopted in 2020, emphasis should be given to embrace innovation technology projects, so as advanced water reuse systems can deal efficiently with environmental risks that may arise based on site-specific conditions and relevant hazardous substances,taking into account national and local legislation. The quality of the reclaimed water should comply with the minimum requirements as set by the Water Reuse Regulation, however, foreseeing the potential concentration of hazardous organic compounds, i.e., pesticides, and thus set the key principles for a complete risk management framework. Minimum quality requirements needs to be revised and settled for agricultural irrigation and aquifer recharge.

In October 2022, the European Commission published a proposal for a new Directive [COM(20220540 final], amending the Water Framework Directive 2000/60/EC, as well as the EU Directives on the protection of Groundwater (2006/118/EC), amended by Directive 2014/80/EE, the Nitrates Directive 91/676/EEC, the Environmental Quality Standards Directive (EQS) 2008/105/EC, amended by Directive 2013/39/EU. This EC proposal substantially revises, among others, the list of priority substances in surface waters. 25 substances are proposed for addition, including a standard for total pesticides. It now includes 68 substances and substance groups. It also identifies five substances and substance groups, as a priority for groundwater management.

On July 2023, the commission published updated progress towards Common Agricultural Policy (CAP) requirements, targeting to reduce by 50% the use and risk of chemical pesticides by 2030 in line with the EU Farm to Fork pesticide reduction and the EU Green Deal strategy. To help achieve these and other goals the CAP must continue to embrace innovation.

Water is a limited source and an increasing challenge at the EU and global level. It is now evident that the intention of the EU to eliminate and regulate the presence of hazardous substances, such as pesticide chemicals in natural waters is a clear trend. It is therefore clear that pollutants targeted by the LIFE PureAgroH2O water reuse project are gaining great attention in the EU policy agenda. Innovation technology, such as the PNFR, can set strategic plans to work towards green deal objectives. In line with the objectives set by CAP requirements, PNFR technology can lead to the elimination of pesticide chemicals in the reclaimed water down to even non-detectable limits for most of them, and their metabolites, overcoming any environmental risk of an accidental release of hazardous materials to the environment, rendering safe the surface and groundwater resources. It can also be easily integrated to the different EU water reuse projects for agricultural operations, independently of the site-specific conditions, providing an end use water of high overall quality characteristics. It can finally be part of a water recycling policy framework in the content of the circular economy action plan, as it can be easily integrated in the industrial process line.  Either for agricultural operations (i.e., agricultural irrigation) or industrial processes (e.g., industrial food processing) the LIFE PureAgroH2O innovation technology can provide reclaimed water of environmentally safe standards towards sustainability via optimum water reuse practices, setting the key principles of the risk management policy framework.