Debris flows caused great damages and influenced the social and economic development in Beijing historically. They have mainly concentrated distribution in the northern mountainous area, e.g., in Miyun and Huairou County. Nearly 40 events were recorded from 1949 to 2010. During that period, the Fanzipai debris flows in Miyun County are the most serious for their serious damages. In 1989 and 1991, the debris flows damaged the minefield, blocked the traffic, destroyed more than 800 houses and caused more than 300 million RMB lose.

The debris flow countermeasures, including both the engineering and ecological projects, will be investigated during this trip in Ketai watershed and Fanzipai village. It is located in the upstream of Baimaguan watershed, and about 130 km from Beijing City.

As the main water supply of the 20 millions of inhabitants in Beijing City, the Miyun reservoir has a storage capacity of 40 billion of water, with a mean depth of 30 meters. This reservoir has 7 dams (2 key dams and 5 Auxiliary dams), with a total length of 4500 meters. It is located about 13 km to Miyun County.

This field trip will take one day on Nov 7, 2018.