Uruguay Revises Water Strategy
Uruguay Revises Water Strategy: From Arazati-Neptuno to Casupá and Public Infrastructure
Uruguay’s government has officially cancelled the controversial Neptuno project, which involved building a privately operated water treatment plant at Arazati on the Río de la Plata.Instead, the administration is moving forward with a new water strategy focused on expanding public infrastructure: upgrading the Aguas Corrientes plant, constructing a new reservoir in Casupá, and developing decentralized solutions like the Solís Chico facility for coastal regions.
Technical and Environmental Basis
Multiple technical reviews concluded that the Neptuno project faced serious environmental risks. These included high salinity levels in the Río de la Plata intake area, increased presence of cyanobacteria, and potential generation of harmful byproducts during treatment. These risks raised concerns about the long-term viability of the plant, especially under drought conditions.
A 2022 government-commissioned study, funded by the Inter-American Development Bank (IDB), determined that the Casupá dam would provide a more reliable and sustainable solution. The Casupá reservoir is projected to increase water security for Montevideo and surrounding areas through 2045, with an estimated cost of US$130 million, partially financed by the CAF (Development Bank of Latin America).
Political Reactions
• Frente Amplio (FA): The ruling coalition sees the shift as a fulfillment of campaign promises. Senator Sandra Lazo (MPP) emphasized the need to “discontinue Neptuno and resume Casupa.” Deputy Felipe Carballo warned that Neptuno would have transferred water control to private firms and potentially cost Uruguay up to US$900 million.
• Partido Nacional (PN): Opposition figures such as Senator Martín Lema criticized the cancellation, stating that Casupá and the new plant lack detailed cost evaluations. He defended Neptuno’s technical merits, including deep intake design and polder reservoir, arguing that it would have ensured resilience.
• Government and OSE: Secretary of the Presidency Alejandro Sánchez announced a 90-day pause on contracts to reevaluate technical and financial details. Minister of Environment Edgardo Ortuño confirmed that Arazati was halted due to unresolved legal and environmental concerns. OSE President Pablo Ferreri stressed that cost projections are still being refined.
Expert Analysis
Water specialists highlight the importance of diversifying sources. Israeli consultant Berger had advised creating dual water supply systems, each capable of covering 70% of peak demand. While Neptuno would have met that criterion, the Casupá and Aguas Corrientes upgrades aim to achieve similar capacity through a decentralized, publicly managed model.
Independent scientists raised alarms about insufficient consideration of technical evidence by past OSE leadership, citing risks of bromates, trihalomethanes, and treatment instability due to Río de la Plata water characteristics. The government now pledges to base all future infrastructure decisions on rigorous technical vetting.
Citizen Impact
* Ensures public ownership and control of critical water infrastructure.
*Targets coastal growth areas with Solís Chico plant.
*Aims to stabilize long-term water tariffs by avoiding large private contracts.
* Enhances resilience against future droughts and environmental variability.
This shift represents Uruguay’s commitment to sustainable, technically grounded, and publicly accountable water management