Explosion at Ritom hydroelectric plant in Switzerland leaves two seriously injured

Blast at the Ritom hydroelectric plant

An explosion occurred at the Ritom hydroelectric power plant in the village of Piotta, situated in the southern Swiss canton of Ticino, on Wednesday morning. Swiss emergency dispatches registered the incident shortly after 9:30 on 9 September 2026, while initial regional bulletins also cited alarms sounding shortly after 10:00. The blast caused significant structural failure, bringing down part of the power station building and scattering debris across the site. Cantonal authorities confirmed that two people sustained severe injuries in the explosion. Early reports from Swiss broadcasters and news outlets, including RSI, bluewin.ch, and 20 Minuten, initially indicated that several people were injured and potentially trapped beneath the rubble of the collapsed building. Later official updates issued by law enforcement clarified that two individuals were confirmed to be in serious condition, while rescue teams continued to verify the status of the damaged premises.

Emergency deployment and site evacuation

A substantial contingent of regional emergency personnel deployed to the industrial complex in Piotta immediately following the blast. The emergency response included officers from the Ticino cantonal police, firefighting crews dispatched from Biasca, and specialized medical teams from the Tre Valli rescue service. The Swiss air rescue organisation Rega mobilized an air ambulance helicopter to assist medical operations and transport the critically injured. Police officers cordoned off the perimeter surrounding the power station, establishing a safety cordon to keep onlookers away and allow emergency vehicles unobstructed access.

A spokesperson for the Ticino cantonal police confirmed the damage and casualty figures in statements provided to Keystone-ATS and regional news outlets.

Part of the installation was damaged. Two people were seriously injured.

Investigation into potential transformer failure

Cantonal authorities initiated a formal investigation to determine the exact cause and operational sequence of the explosion. Early technical assessments cited by regional reporting suggest that the blast may have stemmed from an electrical failure in a transformer during a commissioning test. Investigators and technical specialists are assessing the electrical infrastructure to verify whether equipment testing produced an electrical arc or sudden mechanical breach inside the facility. The Ticino cantonal police announced that further official communications regarding the investigation and the technical circumstances of the accident will be released as forensic work advances.

Infrastructure damage across the Piotta complex

The hydropower complex in Piotta contains two adjacent industrial installations representing different operational eras. The original Ritom hydroelectric power plant has been operating since 1917, providing electricity generation for over a century. Next to this operational facility, a new power plant has been under construction, with commissioning scheduled between 2026 and 2027. News reports from Blick and 20 Minuten noted that it remained initially unclear whether the explosion and subsequent structural collapse affected the active 1917 building or the newly constructed expansion facility. Structural engineers and cantonal emergency personnel continue to assess the stability of the damaged structure before rebuilding and restoration work can proceed.