Key Technology in the Remediation Project of Hongshiyan Landslide-Dammed Lake on Niulan River Caused by “8•03” Earthquake in Ludian, Yunnan

The Hongshiyan landslide dammed lake on the Niulan River is a large-sized one caused by the Ludian 8•03 earthquake in 2014. Based on the uniqueness of the Hongshiyan dammed lake, after the completion of the emergency rescue, the treatment concept of “Eliminating Hazard, Utilizing Resources and Turning Waste into Treasure” was innovatively proposed and this dammed lake was then rebuilt into a large-integrated water conservancy complex with the multiple functions of flood control, water supply, irrigation, and power generation. The project is the first in the world to be developed and utilized immediately after the formation of the barrier dam. This paper systematically introduces the formation of the Hongshiyan landslide dam, the emergency rescue as well as the remediation in the later period. The reservoir has been impounded in 2019, the landslide dam has already retained to a high water level and operated safely. Through the practice of the project, this paper summaries the key technologies such as emergency treatment technology and remediation plan under the lack of information conditions, the comprehensive treatment of the 750 m high slope affected by the intense earthquake and the comprehensive treatment of the 130 m grade landslide dam composed of materials with discontinuous wide gradation, which can provide reference for the emergency rescue, development and utilization of similar landslide-dammed lakes.