Portuguese 
English 
Spanish 
3 min of reading 
0 comments 
The Dispute for the Title of Largest Fish Reservoir in Brazil Has Two Champions: The Castanhao Reservoir in Ceará Is the Largest in Water Volume, but the Ilha Solteira Reservoir Is the Absolute Leader in Fish Production.
The question of which is the largest fish reservoir in Brazil does not have a single answer, but two. The leadership is divided between Ceará, which has the largest water reservoir in the country, and the border of São Paulo with Mato Grosso do Sul, home to the largest fish farming production center.
According to the 2025 Yearbook of the Brazilian Association of Fish Farming (Peixe BR), the production in mesh cages at the Ilha Solteira reservoir surpasses that of any other location. The analysis of the two giants reveals how Brazil utilizes its vast water resources for both water security and to consolidate itself as a power in aquaculture.
Defining “Largest”: The Difference Between Water Volume and Fish Production
To identify the largest fish reservoir in Brazil, it is crucial to separate the two concepts.
-
Drought may be creating stronger superbugs in the soil and helping antibiotic resistance reach hospitals, warns a study highlighting a problem that could grow alongside extreme weather.
-
The biggest scam in history: Napoleon’s France deceived the United States by selling them a territory that was Spanish.
-
Why is the Danakil Desert so dangerous? It has unstable terrain and how extreme temperatures and toxic gases turn the region into one of the most hostile environments on Earth.
-
With a height of 221 meters and a capacity for trillions of liters, Hoover Dam still holds a trick that makes water defy logic.
- Water volume: measures the physical size of the reservoir, that is, its storage capacity.
- Fish production: measures the quantity of fish, in tons, produced at the location annually.
Brazil has notable and distinct leaders in each of these categories.
The Champion in Water Volume: The Castanhao Reservoir in Ceará
When the criterion is the size of the reservoir, the undisputed champion is the Castanhao Reservoir.
- Official Name: Epitácio Pessoa Public Reservoir.
- Location: Alto Santo municipality, on the bed of the Jaguaribe River, in Ceará.
- Capacity: can store an impressive 6.7 billion cubic meters of water.
Inaugurated in 2003, Castanhao is a monumental work of DNOCS (National Department of Works Against Drought), crucial for water security in the northeastern hinterland. It also supports an important fishing and aquaculture activity, with an estimated tilapia production of over 5,000 tons per year.
The Leader in Fish Production: The “Freshwater Sea” of Ilha Solteira
If the criterion is fish production, the title of largest fish reservoir in Brazil belongs to the Ilha Solteira Hydroelectric Plant Reservoir.
- Location: Paraná River, on the border of São Paulo and Mato Grosso do Sul states.
- Annual Production: exceeds 85 thousand tons of fish, mainly tilapia.
The municipality of Ilha Solteira (SP) is today the largest producer of fish farming in waters under Union jurisdiction, consolidating the reservoir as the country’s main aquaculture hub.
Tilapia Farming in Cages
What makes Ilha Solteira a powerhouse is its production model. Tilapia farming is done intensively in mesh cages, which are large floating enclosures.
This system allows a high fish density and optimizes feeding, resulting in productivity far superior to other farming methods, transforming the immense lake of the hydroelectric plant into a true fish factory.
A Champion for Each Criterion
After all, which is the largest fish reservoir in Brazil? The answer is twofold:
- The largest in water volume: The Castanhao Reservoir, in Ceará.
- The largest in fish production: The Ilha Solteira Reservoir, on the border of SP and MS.
The existence of these two giants demonstrates the strength and diversity of Brazil’s water resources and their potential for both supply and food production.
Seja o primeiro a reagir!