A shift in approach to water reuse based on risk management, quality, and adaptation to each use.

Royal Decree 1085/2024: new water reuse regulation
in Spain

The Royal Decree 1085/2024, published on October 22, 2024, replaces the previous Royal Decree 1620/2007 and redefines the regulatory framework for reuse in Spain.

Beyond a technical update, the new regulation introduces a shift in focus: moving from a model based on fixed quality parameters to an approach supported by risk management, aligned with the Regulation (EU) 2020/741 and with a more integrated view of efficient water resource use.

From quality to risk: the central axis of the regulation

The main novelty of the decree is the mandatory incorporation of the Water Reuse Risk Management Plan (WRRMP), which becomes the central element to ensure the safety of the reused water.

This approach requires evaluating not only the quality of the water itself but also the actual conditions of use, exposure, potential environmental impacts, and necessary control barriers for each application.

• Health risks: assessment of exposure and necessary controls to protect health.
• Environmental impacts: analysis of the application environment and possible effects on the environment.
• Specific conditions of use: each destination requires different requirements and management measures.
• Barriers and control measures: the system must be designed and managed to continuously reduce risk.

In practice, reuse ceases to be seen as mere analytical compliance and comes to be understood as a managed system, where design, operation, control, and monitoring are closely linked.

New quality classification and adaptation to uses

RD 1085/2024 introduces a more detailed classification of the quality of reused water, with different classes linked to the intended use and associated exposure level.

Quality classes: A+, A, B, C, D

Each class is related to factors such as:

• Level of human exposure
• Type of user
• Risk associated with final use

This allows for a more tailored application to each case, avoiding uniform approaches and promoting technical solutions more coherent with the destination of the reused water.

Strengthening controls and responsibilities

The new regulatory framework reinforces traceability and control throughout the reuse chain, more clearly defining the agents involved and their responsibilities.

• Clear definition of responsibilities: producer, supplier, and end-user.
• More demanding analytical control programs: with requirements linked to the use and quality class, also incorporating continuous controls of parameters such as flow and turbidity.
• Accredited laboratories: analyses must be carried out in laboratories accredited in accordance with the UNE-EN ISO/IEC 17025 standard.
• Continuous surveillance and validation: control ceases to be sporadic and becomes part of the system's management.

Moreover, closer coordination between the different agents is required, which increases operational complexity but also strengthens health and environmental guarantees of reused water use.

Expansion and consolidation of uses

The decree maintains and develops already considered uses, incorporating greater technical precision depending on the final destination of the reused water.

• Agricultural uses: particularly linked to the European reuse framework for irrigation.
• Urban uses: irrigation, cleaning, and certain non-potable municipal uses.
• Industrial uses: processes and technical applications compatible with the required quality.
• Recreational uses: application in golf courses, sports facilities, and other recreational areas for non-potable uses such as irrigation and maintenance of green areas.
• Environmental uses: applications aimed at aquifer recharge, maintenance of wetlands, and support for aquatic ecosystems, contributing to the conservation and recovery of water resources and natural environments.

Restrictions remain for uses intended for direct human consumption and for those applications where health risks cannot be adequately controlled.

A more demanding and technical framework

RD 1085/2024 not only expands reuse possibilities but also raises the level of technical and documentary demands necessary to implement such solutions with guarantees.

• Preventive approach: management anticipates risk, instead of acting only when incidents occur.
• Technical justification of use: each application must be evaluated and documented specifically.
• Greater specialization: compliance requires technical knowledge, operational control, and an integrated project vision.

This means that reuse ceases to be a sporadic measure and becomes a strategic technical decision, linked to system design, the context of use, and continued risk management.

Implications for the industry

This new regulatory framework generates a double reading for the water sector and for projects seeking to incorporate regeneration and reuse solutions.

Opportunity

• Promotes new reuse projects.
• Encourages optimization of the water resource.
• Strengthens sustainability and resilience criteria in different environments.

Technical complexity

• Higher documentary burden.
• Need for risk analysis and validation.
• Coordinated participation of several agents in the reuse chain.

Technical approach: from regulation to solution

• Analysis of available resource: source, quality, and variability of water to be reused.
• Evaluation of the final use: real needs, exposure, and quality requirements.
• Design of the treatment: selection of appropriate barriers and technologies for each application.
• Integration of WRRMP from the start: as part of the project's technical planning and not as a subsequent procedure.

It is here where reuse shifts from being a regulatory obligation to a strategic technical decision, with direct implications on the viability, safety, and operation of the system.

Regeneration solutions at Envirotecnics

At Envirotecnics, we approach each regeneration and reuse project from a technical perspective, adapting the solution to the available resource, the intended use, and the control and safety requirements posed by the regulation.

Our approach includes:

• Analysis of the resource and context of use: to define the most appropriate strategy from the outset.
• Design of adapted solutions: sized according to technical, operational, and regulatory needs.
• Integration of treatment technologies: according to required quality, destination of the water, and site conditions.
• Implementation and start-up: with a practical vision of operation and continuity of the system:
  • Authorization for the use of recycled water with ACA, Public Health, and competent entities
  • Monitoring, operational control, and quality of the system according to the analytical control program and the Water Reuse Risk Management Plan (WRRMP).
• Monitoring and technical support: aimed at maintaining the performance and safety of the project.