In the heart of southeastern Spain, Almería has turned aridity into an agricultural powerhouse, producing over 3.5 million tons of fruits and vegetables annually. Yet this success coexists with a critical paradox: aquifer overexploitation and increasing saline intrusion threaten the sustainability of a system on which thousands of families and international markets depend. Climate change amplifies this pressure: irregular rainfall, prolonged droughts, and decreasing freshwater availability place intensive agriculture at the core of the global water challenge.
This project breaks away from the extract-and-deplete logic, establishing a regenerative cycle based on the safe, controlled reuse of reclaimed water from local wastewater treatment plants. Through advanced tertiary treatment, filtration, chlorine-free disinfection, and digital quality monitoring, the project delivers irrigation-ready water that replaces groundwater withdrawals and eases pressure on critical underground reserves. The scale is significant: over 2 million m³ per year of reclaimed water can meet up to 15% of the area’s water needs, equivalent to the domestic consumption of 40,000 people.
The strategic objective is twofold: to ensure the water resilience of intensive agriculture in Níjar and to demonstrate that planned reuse, with physical and digital traceability under VWBA 2.0 methodology (A-2: avoided consumption, A-6: safe onsite reuse), is a scalable tool to achieve the Water Positive approach. Traceability is ensured through continuous flow measurement, external quality validation, and georeferencing of beneficiary plots. The project is led by the wastewater treatment plant operator, in collaboration with farmers, cooperatives, and agro-export companies, under a shared governance scheme.
In a European market increasingly demanding ESG standards, and with international buyers already conditioning contracts on responsible water practices, this initiative not only safeguards a vital resource but also positions stakeholders as leaders in the transition toward climate-smart agriculture.
The Níjar basin faces one of the most severe water stress situations in the Mediterranean: aquifer overexploitation, accelerated seawater intrusion, and an agricultural model that, though highly productive, depends almost entirely on a diminishing resource. Today, more than 60% of groundwater withdrawals in the area exceed natural recharge levels, creating a structural deficit that jeopardizes the future viability of intensive farming. Adding to this pressure, European regulations now require producers to demonstrate sustainable water management practices to maintain access to international markets.
The opportunity lies in turning a liability into an asset. Every cubic meter of reclaimed water currently discharged into the sea unused is, in fact, a potential source of safe irrigation and agricultural resilience. Through advanced treatment with online quality control, this project transforms effluents into a reliable water resource, reducing aquifer pressure by more than 2 million m³ per year while avoiding indirect emissions associated with deep pumping and deteriorating water quality. Strategically, this translates into energy savings, improved operational efficiency, and reduced reputational risks.
The benefits materialize in the short term through immediate irrigation flows; in the medium term through partial recovery of groundwater levels; and in the long term through the consolidation of a resilient agricultural model, capable of continuously supplying the European market without compromising its water base. Key actors include the wastewater treatment plant operator, irrigation communities, horticultural cooperatives, and local authorities, all aligned under a governance framework that ensures additionality, intentionality, and traceability of the benefits.
This model is highly replicable in other agricultural regions of Spain and across the Mediterranean arc where water stress is critical. For companies in the agri-food, energy, or retail sectors, joining this initiative means strengthening ESG commitments, differentiating in increasingly demanding markets, and securing production continuity in a context of growing climate uncertainty. The time to act is now: every day lost equals thousands of cubic meters of reclaimed water that could have been converted into resilience for the future.
The proposed solution involves implementing a comprehensive reclaimed water reuse system for agricultural purposes, integrating technologies for capture, advanced treatment, storage, and pressurized distribution. The system will draw from tertiary-treated effluents at wastewater treatment plants that consistently meet irrigation quality standards (e.g., EC < 2.5 dS/m, total coliforms < 1000 CFU/100ml). These volumes will be stored in covered regulation ponds to minimize evaporative losses and distributed through a pressurized hydraulic network to agricultural plots selected based on agronomic eligibility and strategic location within the irrigation system.
The infrastructure will include advanced polishing stations equipped with safety filtration (100–200 micron mesh), ultraviolet disinfection (with automatic dosing and effective dose monitoring), and multiparametric sensors to monitor turbidity, EC, pH, and residual chlorine. The system will also feature automatic valves, high-precision flow meters, and pressure sensors at delivery points, all integrated into a georeferenced digital monitoring platform.
The selection of beneficiary farmers will be carried out in coordination with local irrigation communities (CR Níjar Norte and CR San Isidro), prioritizing farms using localized irrigation and willing to replace groundwater with reclaimed water. The operational model will be governed by formal usage agreements and monitoring plans that allow for traceable and certified volumetric water benefits under the VWBA 2.0 standard, supported by the Aqua Positive platform.
The project will be implemented through a structured technical sequence ranging from initial validation of available resources to the sustained operation of the system, integrating planning, construction, and monitoring activities.
First, a technical diagnostic and institutional agreements phase will be developed, lasting approximately three months. This stage involves exhaustive characterization of the tertiary-treated effluents from the El Toyo, Níjar, and San Isidro Wastewater Treatment Plants through analyses of key parameters such as electrical conductivity, coliforms, turbidity, and nutrient load, in order to confirm their suitability for agricultural irrigation under the criteria established by Royal Decree 1620/2007. Simultaneously, a georeferenced mapping of agricultural plots surrounding the treatment plants will be carried out to identify those with the highest technical viability and willingness to be integrated into the reclaimed water irrigation system. This process will also include formal collaboration agreements with irrigation communities such as CR San Isidro and CR Níjar Norte, wastewater treatment plants operators, and local authorities.
Based on the prior diagnosis, the technical design and feasibility studies phase will take place between months 3 and 6. This stage includes hydraulic modeling of the distribution network, definition of operating pressures, sizing of regulation ponds and polishing stations, and integration of control nodes with multiparametric sensors and a telemetry platform. A simplified environmental impact study will also be drafted, if applicable, and permits will be processed before the Andalusian Government. Technical calculations will consider variables such as design flow, head loss, usable storage volume, and retention time, aiming to maximize the system’s operational efficiency.
The execution and installation phase, projected between months 6 and 12, involves the construction and physical implementation of the system. It includes installing the hydraulic distribution network with high-density polyethylene pipes, constructing regulation ponds with floating covers, and installing pumping stations and technical huts equipped with final treatment systems (120-micron mesh filtration and ultraviolet disinfection). A continuous monitoring system will also be implemented to record real-time data on conductivity, turbidity, residual chlorine, and coliforms. Pressure tests, sensor calibration, and functional validation will be carried out on selected pilot plots to assess the system’s hydraulic efficiency and the delivered water quality.
Finally, from month 12 onward, the operation, monitoring, and scaling phase will begin. This stage will include the deployment of a digitized system for registering and tracing distributed volumes, irrigated hectares, and delivered water quality parameters, integrating this information into a database available for external audits and reporting. Annual performance audits will be conducted under the VWBA 2.0 methodology, validating the volumetric water benefits generated (additionality, permanence, traceability), and preparing reports aligned with international frameworks such as CDP Water Disclosure, ESRS E3, and Act4Water. This phase also envisions the progressive expansion of the system to new agricultural users within the wastewater treatment plants service area, prioritizing farms capable of replacing groundwater abstraction with reclaimed water in a safe and sustainable manner.
This project offers a structural solution to the severe water crisis affecting Campo de Níjar, one of the driest regions in Europe and highly dependent on intensive greenhouse agriculture. By reclaiming water from urban wastewater treatment plants (El Toyo, Níjar, and San Isidro), the project proposes a circular water management model to replace current groundwater extractions with the safe and controlled use of reclaimed water for agricultural irrigation.
The project is designed to capture, refine, store, and distribute reclaimed water through a pressurized hydraulic network to agricultural plots managed by local irrigation communities. It includes the installation of regulation ponds, pumping stations, final filtration, ultraviolet disinfection, and an online monitoring system that controls parameters such as electrical conductivity, turbidity, residual chlorine, and coliforms.
The project will be developed in four phases: diagnosis and institutional agreements, hydraulic system design and permitting, infrastructure installation, and monitoring and scaling. It is expected to replace over 100,000 m³/year of groundwater abstraction with reclaimed water, reducing pressure on critically stressed aquifers such as Campo de Níjar and Bajo Andarax. Additionally, it strengthens the resilience of the agricultural sector, ensures irrigation reliability, promotes circular practices, and aligns water benefits with international frameworks such as CDP Water Disclosure, ESRS E3, Science-Based Targets for Water, and Act4Water.
The project directly supports SDGs 2, 6, 12, 13, 15, and 17. All systems will be integrated into a digital traceability platform, ensuring transparency, additionality, and permanence of the benefits. In this way, the project proposes a real and measurable transformation of the local water management model, adapted to the climate conditions of southeastern Spain and replicable in other water-stressed regions.
