Tsunamis in 2009

July 20, 2009 Tsunami: Xiaowan Reservoir, Yunnan Province, China

July 20, 2009 · 30 m · 2 deaths · Probable tsunami

A tsunami caused by a landslide began at Xiaowan Reservoir, Yunnan Province, China on July 20, 2009. The water rose as high as 30 meters. It killed 2 people.

Where the waves reached

The source of the tsunami. No runup with a place is recorded for it.

  • Under 1 m
  • 1 to 3 m
  • 3 to 10 m
  • 10 to 30 m
  • 30 m and more
  • Height not recorded

Tsunami warnings in force

The tsunami

Date
July 20, 2009
Source
Xiaowan Reservoir, Yunnan Province, China
Cause
Landslide
Maximum water height
30 m (98.4 ft)
Runups recorded
0
Waters
A lake or river, not the ocean
How certain
Probable tsunami
Source location
24.750° N, 100.000° E

The toll

Deaths
2
Missing
12

Where the literature gives no number, NCEI records a description on a scale of 1 to 4, printed here in its words. Damage is in millions of US dollars of the year of the event, not adjusted for inflation.

What the record says

NCEI’s account, from the sources it cites.

Huangtian landslide which located in Xiaowan reservoir is about 7.5 Km away from the Xiaowan dam. Stormed by a very heavy rain, the Huangtian slope failed and about 1 million cubic meters slid into the reservoir, induced 30 meters high huge wave. A wave height about 2m is recorded at the survey site located just in front the dam. (reference #13749)

“Waves up to 30 metres high swept 14 people into the turbulent upper reaches of the Mekong River following a huge landslide into the river in south-western China’s Yunnan province, state media said on Tuesday. Rescue workers recovered two bodies from the river, which is known as the Lancang in China, and were still searching for 12 others missing since they were swept away in the early hours of Monday, the semi-official China News Service said. An estimated 13 hectares of land plunged into the river near the Xiaowan hydroelectricpower station, creating giant waves that engulfed 14 farmers as they camped nearby, the agency said. “ This slide apparently had a surface area of 130,000 square metres and created displacement waves 30 m high. That is a very large landslide! (reference #13750)

More

Every tsunami in 2009The 2000sTsunamis of ChinaThis day in weather historyAlerts in force

Sources

Tsunami events and runups from NOAA’s National Centers for Environmental Information, Global Historical Hazard Database, cited as NCEI/WDS, doi:10.7289/V5PN93H7. Public domain. Read 2026-09-24. NCEI tsunami event 5915.