This is a facile assumption but it's almost certainly false. The Banqiao dam disaster killed 25,000 people directly, and destroyed 6 million buildings (it caused 145,000 further deaths due to famine). Such a disaster far outstrips even Chernobyl, which was about as maximally bad as any nuclear reactor accident can be (runaway fission reaction generating massive amounts of radionuclides; no worthwhile reactor containment structures; the reactor core melting down, catching on fire, and spewing huge amounts of radiation into the wind).