In a world where more than 2 billion people still lack safe access to water and where 80% of wastewater is discharged untreated, every cubic meter regenerated represents an opportunity for transformation. The reuse of treated wastewater, once considered a last-resort option, has now become a cornerstone of climate resilience, water efficiency, and urban circularity. In this context, the project developed at the Wastewater Treatment Plant (WWTP) takes on strategic value: it does not merely treat effluents, but transforms them into a new, reliable, safe, and traceable source of water for agricultural, industrial, or environmental uses.
Located in a setting marked by increasing pressure on water resources and restrictions on freshwater withdrawals, the project addresses a dual challenge: reducing dependence on natural sources while increasing the availability of reclaimed water that meets strict quality standards. Its implementation closes the water cycle with a focus on energy efficiency, public health, and technical traceability, fully aligned with the principles of Volumetric Water Benefit Accounting (VWBA) under Volume Treated. The intervention also ensures that the benefit generated is additional, measurable, and intentional, delivering usable volume that would not otherwise be available.
This forward-looking approach turns an environmental liability into a strategic asset. The recoverable flow, previously discharged into the environment, is captured through advanced tertiary treatment and redirected to uses that displace freshwater consumption. In practical terms, this is equivalent to supplying thousands of residents or irrigated hectares each year without new abstractions. The commitment to water reuse is not just a technical imperative: it represents a vision of the future, where cities, industries, and agriculture work together under a new common code of sustainability. This project is tangible proof that this future is already underway.
The project emerges from a compelling opportunity: to transform the flow treated by the WWTP, previously unutilized, into a safe, traceable, and regenerative source of water for high-demand activities. The solution is implemented within an existing facility, through the integration of tertiary treatment technologies such as advanced filtration, chlorine-free disinfection, and online monitoring systems, enabling compliance with stringent reuse standards. Through this intervention, a significant volume of water, potentially hundreds of thousands of cubic meters annually, is recovered instead of being discharged unused. Every liter regenerated translates into a direct reduction in pressure on natural sources, improved local availability, and a new water supply option for key sectors.
Immediate benefits include the substitution of freshwater withdrawals, improved water efficiency at the catchment scale, and reduced operational water risk for industrial or agricultural users. Additionally, the project optimizes plant performance, lowers its environmental footprint, and ensures compliance with increasingly strict regulations on circular economy and efficient water use.
This solution is made possible through the coordination of a technical-operational consortium involving the WWTP operator, specialized technology providers, and a technical structurer ensuring alignment with VWBA 2.0 and the 2030 Agenda. The model features full digital traceability, third-party verification, and predictive maintenance protocols, making it a replicable case for hundreds of WWTPs in similar contexts. Companies with ambitious ESG targets, territorial presence, or reputational needs will find here a platform ready to adopt, scale, and communicate as part of their tangible contribution to the SDGs.
Acting now is crucial. The windows of opportunity to replace freshwater with reclaimed water are rapidly closing in many regions due to source saturation or new regulatory restrictions. Being a pioneer in water reuse not only ensures operational security, it offers strategic visibility, alignment with international frameworks, and a powerful narrative that positions those leading this change as key players in the global water transition.
The project proposes to establish an integrated and scalable system for reclaimed water reuse from the Reclaimed Water Reuse Plant, based on three interdependent pillars:
This integrated approach ensures not only an increase in the volume of reclaimed water utilized but also the consolidation of an adaptive and resilient management model aligned with the requirements of the VWBA 2.0 framework.
The technical implementation of the project includes the integration of a set of technologies and actions aimed at maximizing efficiency, traceability, and sustainability of the tertiary treatment system at the Reclaimed Water Reuse Plant. The core of the project relies on advanced tertiary treatment using ultrafiltration (UF) and reverse osmosis (RO), which produce high-quality effluent suitable for demanding non-potable uses. UF acts as a physical barrier for suspended solids, viruses, and bacteria, while RO removes dissolved salts, emerging contaminants, and micro-organic pollutants, reaching standards comparable to potable water for specific applications.
A key proposed improvement is the incorporation of next-generation antiscalants and specialized biodispersants. These advanced chemicals prevent mineral scaling and biofilm formation on membranes, two factors that traditionally reduce the hydraulic and energy efficiency of the system. This intervention is expected to increase the UF/RO system recovery rate from 75% to 80%, significantly increasing the daily volume of reclaimed water available without increasing influent flow or modifying existing infrastructure.
The operation will be supported by an intelligent monitoring network based on SCADA technology. This system will enable real-time supervision of parameters such as flow, pressure, turbidity, conductivity, and residual chlorine, ensuring operational stability and safety. The data will be integrated into the Aqua Positive digital platform via API to ensure external traceability and validation of the generated impact, facilitating reporting under frameworks like CDP Water or European ESRS.
From a field monitoring perspective, multiparameter sensors will be strategically located throughout the system, both within the plant and in the secondary distribution network to be developed as part of this project. This network will channel reclaimed water to identified priority consumption points: municipal green spaces, sports facilities, nurseries, and peri-urban agricultural areas.
Finally, implementation will be carried out through a network of key partnerships. EPSAR, as the infrastructure owner, will ensure regulatory viability and operational sustainability; Aguas de Alicante, as the technical operator, will execute and maintain the operational improvements; the City of Alicante will facilitate urban integration of reclaimed water into green space and service planning; and peri-urban irrigation communities will act as strategic end users, enabling a rural-urban synergy that maximizes the project’s impact.
This technological and operational integration forms a robust and replicable proposal that positions the Reclaimed Water Reuse Plant as a benchmark for water reuse in the Mediterranean region.
The project is being developed in a phased approach to ensure technically and operationally effective implementation, starting with the identification and prioritization of areas where reclaimed water use represents a real opportunity to substitute potable water. This stage involves territorial diagnostics in collaboration with the municipality and local stakeholders to select spaces such as public parks, nurseries, sports fields, and peri-urban horticultural sectors.
In parallel, operational adaptation of the plant’s tertiary treatment train is addressed. This includes actions such as optimizing chemical cleaning (CIP), adjusting backwash sequences, and controlling both organic and inorganic fouling. The introduction of specific antiscalants and biodispersants will allow sustained improvement in UF/RO system efficiency without altering existing infrastructure.
Once production efficiency improvements are secured, construction of a secondary distribution network will proceed. This network will be technically tailored to the type of use and will include pressure-regulating valves, flowmeters, and controlled delivery points. Its design will prioritize proximity, ease of connection, and integration with existing irrigation networks.
Finally, a comprehensive control system will be activated, including real-time sensors, digital platforms for traceability of reused volumes, and external validation mechanisms. This phase will also include training for operational staff and the establishment of protocols for systematic data reporting.
Beyond the immediate improvement in system efficiency and the increase in reclaimed water availability, this intervention represents a replicable model for other Reclaimed Water Reuse Plants in Mediterranean coastal zones. Its value lies not only in the amount of water reused but in the potential to consolidate resilient urban infrastructure aligned with circular water economy principles and climate change adaptation.
