Santa Lucía River

For a large part of its course it forms the limit between the departments of Florida and San José on one bank and Canelones and Montevideo on the other.

Its outlet is the Río de la Plata, forming a small delta, in which Tiger Island is located.

[2] The river is part of an important agricultural zone in Uruguay producing maize and corn.

[2] A 2008-2009 study found phosphorus and nitrogen pollution exceeding both local and international standards and causing algae blooms.

[3] Since a 2013 algea bloom, the Canelones Department and national government have been encouraging dairy farmers and other animal agriculture rpdoucers to improve their effluent management from animal operations, including settling basins and other waste management practices.

Santa Lucía river at San Ramón
The river is heavily used as a water supply, and the failure to plan for a multiyear drought in 2023, led to a water crises in Uruguay. Pictured is the OSE water reservoir and purification station at Aguas Corrientes .