Field survey of the slope collapse in Takushi, Urasoe City, caused by Typhoon No. 6 in 2023

8/7 2023

Typhoon No. 6, which struck Okinawa Island from August 1st, 2023, recorded a maximum precipitation of 32.5 mm/hr in Naha on the 2nd. Due to heavy rain caused by this Typhoon No. 6, a landslide occurred in Takushi, Urasoe City. We conducted an investigation of the landslide site on August 7th, after the typhoon had passed.

To the north of the cliff collapse site flows the Takushi Mae River, and the surrounding area is a steep slope with a gradient of over 30 degrees. It is believed that this cliff collapse occurred due to the collapse of a retaining wall supporting a facility parking lot built on this steep slope.

Topographical map

The next photo shows the entire cliff collapse area. The size of the collapse was estimated from the person's size. The height of the collapse is estimated to be about 10 meters, and it collapsed over a width of about 15 meters.

Full view of the land slide

Bottom-up view