China's May 2008 Wenchuan quake formed Tangjiashan lake, prompting evacuations
In May 2008, China faced a huge flood risk after the Wenchuan earthquake triggered a landslide that blocked the Tongkou River, forming a shaky lake called Tangjiashan.
With water rising fast and millions at risk downstream, officials quickly evacuated people and came up with an engineering fix to keep things under control.
Engineers built 475m spillway
More than 250,000 residents from areas like Beichuan and Mianyang were moved to safety as engineers raced against time.
Using airlifted heavy machinery, they built a 475-meter spillway to safely drain water from the unstable lake, preventing disaster and showing how smart planning can save lives.
Lessons applied to 2018 Baige landslide
This operation became a textbook example of how early evacuation and creative engineering can prevent major disasters: lessons that proved useful again during later emergencies like the 2018 Baige landslide.