HCB opens mid-bottom spillway to guarantee the ecological flow of the Zambezi River

According to the punctual maneuver of 13 hours, on September 20th, it aims to ensure the flow of the river during the total shutdown of the Songo Substation.

Cahora Bassa Hydroelectric Power Plant, SA (HCB) informs riverside communities along the Zambezi River, and the general public, that it will proceed, on September 20, 2026, between 5:00 AM and 6:00 PM, with the opening of a mid-bottom spillway at 80%.

This is a specific, controlled, and technically approved maneuver that does not alter the prudent water management strategy adopted by HCB in light of the outlook for the upcoming rainy season.

The measure was adopted following the complete shutdown of the Songo Substation, within the framework of environmental requirements applicable to the implementation of the annual maintenance program for the power generation park. The objective is to guarantee the compensation of the ecological flow of the Zambezi River.

Thus, opening the spillway will ensure the continuity of flow along the river, contributing to the maintenance of the ecological flow and the conditions necessary for the balance of ecosystems and the activities carried out by riverside communities.

The operation falls within the procedures for careful and cautious management of the water resources of the Cahora Bassa reservoir, taking into account the operational conditions of the system and the hydrological and climatic forecasts for the next rainy season, including scenarios associated with the El Niño phenomenon.

HCB reiterates its commitment to the safety of communities, the responsible management of water resources, and the preservation of the ecological balance of the Zambezi River, keeping stakeholders duly informed about relevant operations.