We are living a decisive moment: the climate crisis and increasing water scarcity threaten a global deficit of up to 40% of freshwater by 2030, while millions of cubic meters of highly contaminated leachates are generated every year, compromising aquifers and coastal ecosystems. In the Canary Islands, where water availability critically depends on desalination and reuse, the Arico Environmental Complex represents both a challenge and a strategic opportunity. Each optimized cubic meter is equivalent to the daily consumption of more than three households, and each additional percentage point of efficiency prevents discharges that were previously wasted.
The opportunity is clear: to optimize the reverse osmosis (RO) plant at Arico to increase recovery, reduce specific consumption, stabilize permeate quality and minimize brine discharges, framing the intervention within a Water Positive roadmap measurable through VWBA 2.0. This is not only about improving technical efficiency, but about changing the operational logic: moving from a reactive, cost-intensive scheme to a high-performance platform that transforms waste into a resource. The quantification of benefits will follow VWBA indicators: volume treated, reduction of extraction/consumption through internal reuse and, where applicable, volume captured or recharged through complementary solutions.
In Europe, and especially in island regions, regulatory pressure and leachate management costs have increased by more than 20% in the last decade, while the adoption of high-recovery technologies remains limited, making Arico a pioneering case. The strategic objective is to transform Arico into an insular benchmark for high-efficiency leachate treatment, reducing brine discharges and energy consumption per cubic meter of permeate, and demonstrating additionality, traceability and intentionality under Water Positive and VWBA. Located in Tenerife, Spain, the complex responds to the urgent need to manage leachates sustainably, relieving pressure on catchments and improving insular water resilience. Governance involves the Cabildo and complex operator, the technology integrator, the membrane chemical supplier (AWC), accredited laboratories and a third-party VWBA verifier, ensuring physical traceability (flows, SDI, ΔP, CIP logs) and digital traceability (SCADA/IoT, data-lake, audit of methods and inputs).
Located in the Arico Environmental Complex in Tenerife, this project addresses an urgent technical and environmental challenge: the low performance of the reverse osmosis (RO) leachate plant due to scaling and fouling in the membranes. The system currently suffers from efficiency losses and high energy consumption. To reverse this situation, the intervention focuses exclusively on increasing efficiency through the controlled dosing of high-performance antiscalant products developed by AWC. The incorporation of these antiscalants, adjusted to the specific composition of the leachates, prevents mineral scaling and reduces fouling, increasing net recovery from the current ~70–80% to a target of 80–90%.
The impact is tangible: each additional cubic meter of permeate reduces consumption from network or groundwater sources, generating a volume reportable under VWBA as volume treated and reduced extraction/consumption. Immediate benefits include less brine discharged, higher permeate yield, reduced kWh per cubic meter, lower cleaning frequency and longer membrane life. At the same time, strategic returns are consolidated: robust regulatory compliance, operational resilience to variations in flow and contaminant load, and the creation of auditable VWBA assets that strengthen Water Positive and ESG goals.
This model is made possible thanks to the collaboration between the Cabildo and the complex operator, the technology integrator, the membrane chemical supplier (AWC), and accredited laboratories, with validation by a third-party VWBA verifier. Regulatory and cost pressures in Europe make it critical to act now, and position Arico as a pioneering and replicable model: the same approach of diagnosis, optimized dosing and VWBA verification can be scaled to other environmental and industrial complexes. For companies seeking leadership in sustainability, involvement in this type of project not only means fulfilling ESG objectives, but also gaining visibility, competitive differentiation and early alignment with increasingly strict regulations.
Project implementation is structured in several clearly defined stages that allow for a comprehensive approach. In the initial phase, baseline characterization is performed, including membrane autopsies to identify the main foulants , from inorganic scaling (sulfates, carbonates, silica) to organic matter, biofouling and metals. This information supports the design of a specific chemical program incorporating multi-threshold antiscalants, non-oxidizing biocides for biofilm control, and acid and alkaline cleaning sequences adapted to the predominant compounds. A robust pretreatment is established with SDI control, possible coagulation or mild oxidation steps, ultrafiltration or optimized cartridge filters, and pH adjustment to ensure maximum process efficiency and stability.
In the second phase, operational optimization is implemented by adjusting recovery set-points per stage, monitoring pressure drop and programming flushing and CIP according to real conditions, with recirculation balances and blending strategies to maximize efficiency. Operation is supported by a digital scheme with SDI, NTU and ATP sensors, as well as conductivity and ammonium analyzers for normalization of flow and salinity data. A specific dashboard linked to VWBA facilitates real-time calculation of volumes treated and reductions in extraction or consumption when permeate replaces external sources.
Expected benefits include a net recovery increase of 5–15 percentage points, a significant reduction in energy consumption per cubic meter treated, fewer cleanings and extended membrane life. These achievements translate into an auditable annual report of volumes treated and replaced in accordance with VWBA, providing additionality and traceability. Co-benefits include reduced brine discharge, lower chemical use and carbon footprint reduction, along with social and economic benefits such as increased water security, stronger regulatory compliance and operating cost savings.
The deployment is not without risks. Variability in leachate composition can affect performance, which is mitigated with buffer tanks and online control systems. The presence of silica and metals requires specific antiscalants and pH control, while biofouling is prevented with non-oxidizing biocides and programmed flushing. To avoid irreversible fouling, cleaning protocols under condition and standardized operating manuals are established. Scenarios of technological failure, extreme climatic events or social acceptance are also considered, with contingency plans, operational redundancies and shared governance with external verifiers. Long-term climate resilience is ensured through operational flexibility, continuous monitoring and safety protocols including contamination prevention, management of potential saline intrusions and continuity of supply plans.
Finally, the proposed solution is hybrid, combining gray technologies with digital tools, and was chosen after evaluating alternatives such as constructed wetlands or advanced biological treatments, which proved less suitable for the high salinity of Arico leachates. Its operating capacity allows for the treatment of significant daily volumes with potential for replication in other island and continental complexes where leachate management is a growing problem.
The choice responded to criteria of efficiency, cost, impact, replicability and regulatory compliance, ensuring alignment with the Water Positive strategy and VWBA principles of additionality, traceability and intentionality. Its scalability is high in regions facing similar pressures, supported by regulatory frameworks promoting water circularity and by public-private partnerships facilitating financing and expansion. Arico is thus positioned as a pioneering model capable of inspiring and multiplying solutions in other territories.
Project implementation will follow a phased and adaptive scheme, advancing in an orderly manner from diagnosis to final validation and continuous operation. In the first stage, a comprehensive diagnosis and baseline definition will be carried out, including characterization campaigns of key parameters such as COD, ammonium, conductivity, SDI and metals. Membrane normalization tests, chemical trials and jar tests will identify optimal antiscalant doses, and KPIs together with VWBA parameters will be defined to serve as references for comparing the with-project versus without-project scenarios.
The second stage will consist of execution and optimization. In this phase, controlled dosing of AWC antiscalants adjusted to leachate composition will be implemented, along with calibration of dosing equipment, operator training and integration of control dashboards with alarms and reports. Recovery set-points will be dynamically adjusted to maximize performance, supported by a preventive and predictive maintenance plan including condition-based cleaning, periodic calibrations and stock management. This stage also strengthens the monitoring system with IoT sensors, flowmeters and SCADA to ensure real-time digital traceability.
The third stage will focus on validation and technical closure, with a 60 to 90-day period of stable operation to confirm system behavior and document improvements against the baseline. During this period, data will be collected for KPIs such as recovery percentage, kWh per cubic meter, cleaning frequency, specific chemical consumption and volumes of permeate recovered and reused. These results will be audited by third parties to ensure reliability and verifiable reports will be issued to consolidate model replicability.
Throughout all phases, physical water traceability is ensured by flowmeters and mass balances, while digital traceability is guaranteed through SCADA and IoT platforms with automatic records and alarms in case of deviations such as high SDI, rejection drops or abnormal increases in chemical consumption. Governance involves the technical operator of the complex, the AWC antiscalant supplier, accredited laboratories and an external verifier, each with clear responsibilities in operation, maintenance, monitoring and validation. Finally, the system is integrated into a continuous improvement scheme including data feedback, technological updates and periodic comparison between with-project and without-project scenarios, ensuring the permanence of benefits over time.
The project will comprehensively optimize the Arico leachate reverse osmosis plant through the application of high-performance antiscalants developed by AWC, complemented by a robust pretreatment scheme, advanced control and VWBA verification. The main intervention consists of increasing RO efficiency through controlled dosing of specialized chemicals that prevent mineral scaling and reduce membrane fouling. Technically, the process is structured into baseline characterization, chemical selection and SOPs, operational adjustments and cleaning cycles, advanced sensorics and control dashboards, and verification under VWBA methods. The system’s nominal capacity allows for the daily treatment of significant volumes of leachate, ensuring superior and stable performance.
The relevance of this solution lies in addressing a critical challenge for Tenerife: the accumulation of saline and organic-rich leachates that pressure aquifers and coastal ecosystems. Compared to the baseline situation of low performance, high energy consumption and large brine discharges, the application of antiscalants achieves higher recovery rates, reduced energy footprint and better permeate quality. This intervention complies with European reuse and discharge regulations, as well as water quality standards recognized by WHO and ISO, ensuring regulatory compliance and technical consistency.
Expected results include a net recovery increase of 5 to 15 percentage points, thousands of additional cubic meters of water recovered and reused annually, measurable reduction of kWh per cubic meter treated, fewer cleaning events and longer membrane life. Improvements in water quality are expected through reduced conductivity and critical contaminants. Additional benefits include lower emissions linked to energy use, reduced saline discharges and contribution to the island’s water security.
Strategically, the project enables traceable Water Positive assets, strengthens the social license to operate and enhances ESG reputation for stakeholders, positioning Tenerife as a replicable showcase of high-efficiency leachate treatment. Replicability is ensured through standardized methodology and KPIs applicable to other island and continental complexes with similar challenges. It adds value to the institution’s Water Positive roadmap, aligns with global commitments such as SBTi, NPWI and SDGs, and generates tangible benefits in regulatory compliance, competitive differentiation and operational resilience.
The final expected impact is a positive contribution to the catchment water balance through significant recovery volumes, reduced pressure on aquifers and strengthened resilience to climate change. Socially, it brings water security, supply stability and community confidence, while creating specialized jobs in operation and maintenance. For investors, clients and society, the project demonstrates how technical innovation applied to a local challenge can become a global reference in the transition to a regenerative economy, where each treated cubic meter translates into efficiency, sustainability and a shared future.
