Belo Monte hydrograph and Volta Grande flow reduction
- As my flow fell in the Volta Grande, first the fruit-eating fish and then the carnivorous fish disappeared. Mongabay
- In January 2023 about 75% of my water went to the power plant, according to the federal prosecutors' office. Ministério Público Federal (MPF), Pará
- In the reach where my flow was reduced, fish died and forest dried, the sources report.
- About 30 tonnes of my fish died.Weight of the fish counted above, 2015–2019.
- 16,000 people were displaced or listed for relocation. not independently verifiedGovernment figure for people displaced; critics give 20,000 to 50,000. Reported but not independently verified.
- At least (critics' range 20,000 to 50,000) 20,000 people were displaced or listed for relocation. not independently verifiedCritics' figure for people displaced. Reported but not independently verified.
- Government and regulators Federal prosecutors (MPF): More than 85,000 fish, about 30 tonnes, died at the turbine intakes in 2015–2019; the hydrograph failed; about 75% of the water went to the power plant in January 2023. Ministério Público Federal (MPF), Pará
- Press and investigations Mongabay: Fishers confirmed scientists' warning about the river; fruit-eating and then carnivorous fish disappeared from the Volta Grande. Mongabay
- Company or project Norte Energia: The effects were smaller than predicted (paraphrase as reported by Mongabay). Mongabay
- Government and regulators Federal prosecutors (MPF): The hydrograph failed. Ministério Público Federal (MPF), Pará
- Courts Brazilian court (not identified in the sources): Ordered the flow plan reorganised in December 2025 after the consensus hydrograph was documented as unworkable. Ministério Público Federal (MPF), Pará
- Company or project Norte Energia: Appealed the order (the sources say "the company" appealed).
Federal prosecutors in Brazil reported that the flow schedule for the Volta Grande reach of the Xingu River below the Belo Monte dam had failed, and a court ordered it revised in December 2025. Reports cite fish deaths at the turbine intakes and the loss of fish species in the reduced-flow reach.
About 30 tonnes, according to federal prosecutors as reported by Mongabay (8 June 2023).
Status As of December 2025: a court ordered the Belo Monte flow plan reorganised; the company appealed; no ruling on the appeal found.
- Norte Energia (operator) — Operates the power plant to which about 75% of the water went in January 2023. Ministério Público Federal (MPF), Pará
- Fishers of the Volta Grande — Fish species disappeared from the reduced-flow reach; a fisher said they were spending more on working than they earned; about 6,000 fishers are listed. Mongabay
- Riverside communities — The settlement area set aside for them was reduced from 32,000 hectares to 9,000 hectares. Mongabay
- Fish of the Xingu River — More than 85,000 fish, about 30 tonnes, died at the turbine intakes in 2015–2019; fruit-eating and then carnivorous fish disappeared from the Volta Grande. Mongabay
What happened
Belo Monte is a hydroelectric dam on the Xingu River in Brazil, operated by Norte Energia. The sources describe a reduction of flow in the river's Volta Grande section and a flow schedule for it, known as a hydrograph. A "consensus hydrograph" for Belo Monte was documented in court as unworkable.
According to the federal prosecutors' office (MPF), the Belo Monte hydrograph failed, and about 75% of the water went to the power plant in January 2023. A court ordered the flow plan to be reorganised in December 2025. The sources say the company appealed.
According to federal prosecutors, as reported by Mongabay, more than 85,000 fish, about 30 tonnes, died at the turbine intakes between 2015 and 2019. As flow in the Volta Grande fell, fruit-eating fish disappeared first and then carnivorous fish. A fisher identified as "Mambira" said that fishers were spending more on working than they earned. In the reduced-flow reach the sources also report fish deaths and drying of forest.
Norte Energia said the effects were smaller than predicted. The settlement area set aside for riverside communities was reduced from 32,000 hectares to 9,000 hectares. Mongabay's summary lists about 6,000 fishers alongside the fish-kill figure.
- 2015Start of the 2015–2019 period in which, per federal prosecutors, more than 85,000 fish died at the turbine intakes
- 2023January: about 75% of the water goes to the power plant (MPF); 8 June: Mongabay reports fishers' accounts
- 2025November–December: MPF presents data on the hydrograph's failure; a court orders the flow plan reorganised; the company appeals
What was said
Where accounts differ
Each party's account, side by side, with its source. The record does not settle these points; it shows them.
More than 85,000 fish, about 30 tonnes, died at the turbine intakes in 2015–2019; the hydrograph failed; about 75% of the water went to the power plant in January 2023.
Ministério Público Federal (MPF), ParáFishers confirmed scientists' warning about the river; fruit-eating and then carnivorous fish disappeared from the Volta Grande.
MongabayThe effects were smaller than predicted (paraphrase as reported by Mongabay).
MongabayThe hydrograph failed.
Ministério Público Federal (MPF), ParáOrdered the flow plan reorganised in December 2025 after the consensus hydrograph was documented as unworkable.
Ministério Público Federal (MPF), ParáAppealed the order (the sources say "the company" appealed).
How it looked
Shown
- The effects of the dam were smaller than predicted.Norte Energia, as reported by Mongabay (paraphrase; the English wording was not seen) · Mongabay
Recorded
- More than 85,000 fish, about 30 tonnes, died at the turbine intakes between 2015 and 2019, according to federal prosecutors.
- In the Volta Grande, as flow fell, fruit-eating fish disappeared first and then carnivorous fish.
- About 75% of the water went to the power plant in January 2023; a court ordered the flow plan reorganised in December 2025.
- The settlement area for riverside communities was reduced from 32,000 hectares to 9,000 hectares.
Who gained
Reached nature or the ground
Gained elsewhere
Responses on record
- Norte Energia (June 2023): Said the effects were smaller than predicted (paraphrase as reported by Mongabay). · Mongabay
- Norte Energia (2025): Appealed the court order to revise the hydrograph (the sources say "the company" appealed).
- Federal Public Prosecutor's Office (MPF) (November–December 2025): Reported that the Belo Monte hydrograph failed and that about 75% of the water went to the power plant in January 2023. · Ministério Público Federal (MPF), Pará
In court and with insurers
Lawsuits and rulings
- 2025-12OngoingOrder to revise the Belo Monte hydrographBrazilian court (not identified in the sources) · Civil · Not stated; the Federal Public Prosecutor's Office (MPF) published the data on the hydrograph's failure → Norte Energia (operator; the sources say "the company" appealed)
The court ordered the flow plan to be reorganised in December 2025; the company appealed. The "consensus hydrograph" was documented in court as unworkable. Ministério Público Federal (MPF), Pará
Insurers
What nature saw
Nature's report opens this page. Below: further outcomes measured on the ground.
What we don't know
Nature
Figures
- Insufficient People displaced: Government figure for people displaced; critics give 20,000 to 50,000. Reported but not independently verified.
- Insufficient People displaced: Critics' figure for people displaced. Reported but not independently verified.
Record
- Insufficient Reported but not independently verified: the number of people displaced is given as 16,000 by the government and as 20,000 to 50,000 by critics (America Magazine, 15 July 2019).
- Insufficient Reported but not independently verified: construction contractors in the Belo Monte tender were reported to have made cartel settlements, and confessions were reported that 1% of the contract value went to ruling parties (IHU Unisinos, 18 November 2016).
- Insufficient Reported but not independently verified: IBAMA's technical staff reportedly recommended in November 2010 against a partial installation licence before the conditions of the preliminary licence were met, yet clearing of 238 hectares was permitted; Minister Izabella Teixeira said IBAMA had not issued a negative opinion (Amazon Watch, 16 November 2010).
Did the harm stop?
The sources do not record that the flow reduction or the fish losses have stopped; a court ordered the flow plan revised in December 2025 and the company appealed.
Who paid?
Reports place the losses on fishers in the Volta Grande and on riverside communities whose settlement area was reduced; the operator said the effects were smaller than predicted.
Sources
Government and regulators
- COP30: MPF details the failure of the Belo Monte hydrograph and presents data on the collapse of the Xingu River (title translated from the URL)Ministério Público Federal (MPF), Pará · 2025
Press and investigations
- The struggles of families uprooted by Brazil's Belo Monte reveal the dam's dark side (title from the URL)America Magazine · 2019-07-15
- Belo Monte cartel may yield billion-dollar fines to contractors (title translated from the URL)IHU Unisinos · 2016-11-18
Communities and civil society
- Construction of the Belo Monte dam could be delayed (title from the URL)Amazon Watch · 2010-11-16
Connected cases
- Federal prosecutors say Belo Monte dam's Xingu flow schedule collapsed in 2025 Brazil · 2010–2025 Related matter
- Norte Energia (Company) — here: Operator of the Belo Monte dam; there: operator of the dam
- Bruno Pereira and Dom Phillips killing (Brazil) Brazil · 2022–2026
- Federal Public Prosecutor's Office (MPF) (Public authority) — here: Federal prosecutors; reported the hydrograph failure and the fish-kill count; there: Federal prosecutors; brought the charges against the accused
- Pará forest carbon credit schemes face suspension and lawsuits Brazil · 2023–2026
- Federal Public Prosecutor's Office (MPF) (Public authority) — here: Federal prosecutors; reported the hydrograph failure and the fish-kill count; there: sued to annul the LEAF deal; wrote to the state in 2026
- Samarco Fundão dam collapse (Mariana): the settlement and the court cases Brazil · 2015–2026
- Federal Public Prosecutor's Office (MPF) (Public authority) — here: Federal prosecutors; reported the hydrograph failure and the fish-kill count; there: Federal prosecutor; brought the 2016 criminal charges
- Vale Brumadinho dam collapse Brazil · 2019–2027
- Federal Public Prosecutor's Office (MPF) (Public authority) — here: Federal prosecutors; reported the hydrograph failure and the fish-kill count; there: Federal prosecutor; re-filed indictment (2023)