The Mediterranean region, where Portugal is located, is expected to encounter changes in rainfall patterns, with potential decreases in annual precipitation and increased variability, exacerbating water scarcity. Even though Portugal has a lot to gain from the usage of reused wastewater, its adoption remains negligible, and there hasn’t been a significant evolution over time.

There are several factors that justify the weak adoption of wastewater reuse in Portugal, namely the fact that this kind of technology requires significant amounts of investment and there are not enough financial incentives for the potential users. In 2007 ERSAR developed a recommendation which meant to clarify the regulated entities about the specificities of the production and usage of reused wastewater. Despite ERSAR’s efforts, only in 2019 was published the first Portuguese legal framework for wastewater reuse defining the minimum requirements and establishing the permitting process. With the growing awareness and importance about this topic, ERSAR considered it was important to create a new recommendation with a set of orientations regarding wastewater reuse, with a particular focus on the economic regulation of this activity.

Consequently, the subject of this presentation focuses precisely on ERSAR’s new recommendation, highlighting amongst other topics, the rules for the tariff definition, instructions for service contracting, considerations about monitoring and quality control, rules about signage and delivery points, among other topics.

Even though progress is being made in Portugal, this recommendation is one of the first steps towards the goal of mainstreaming the usage and production of reused wastewater. As any new paradigm, it comes with a few obstacles that must be overcome, but with the commitment of all relevant stakeholders, it can only be expected that in the near future reused wastewater will become a relevant alternative source of water in Portugal.