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

The change responds both to the need to align with Regulation (EU) 2020/741 and to the intention of moving from a model focused on fixed parameters to one based on risk management, much better adapted to the actual use of reclaimed water.

The main difference lies in the approach. The previous framework relied mainly on water quality tables associated with specific uses. The new decree, aligned with Regulation (EU) 2020/741, maintains analytical criteria but integrates them into a broader system based on risk management. This means it is no longer enough to simply “comply with a table”. It is now necessary to justify the intended use, assess exposure, establish control barriers and document everything within the WRRMP.

The Water Reuse Risk Management Plan (PGRAR) is the core document of the new regulatory framework. It analyses the system, identifies health and environmental risks and defines prevention, control and monitoring measures.

It is mandatory because the decree no longer focuses exclusively on water quality and now requires proof that the final use is safe within its actual context.

The WRRMP must include, at minimum:

• Description of the system and the stakeholders involved.
• Assessment of health and environmental risks.
• Definition of barriers and control measures.
• Analytical monitoring and surveillance programme.
• Incident response procedures.

Its preparation requires detailed technical knowledge of the resource, the intended use and the application environment.

Royal Decree 1085/2024 establishes five quality classes: A+, A, B, C and D, ranked from highest to lowest level of requirement.

The choice of class depends on the intended use, the level of human exposure, the type of user and the risk associated with the final application.

For any quality class and for all uses, continuous monitoring of flow rate and turbidity is required at minimum.

The starting point is analysing the available resource, the intended use and the associated risk. Before defining the technology, it is necessary to understand what type of water is available, what it will be used for and under which conditions it will be applied.

The regulation does not impose specific technologies, but rather results and guarantees. Depending on the required quality class and intended use, biological, physico-chemical, filtration, disinfection, membrane or other treatment barriers may be combined.