Abstract
This is a field survey report on the heavy rainfall disaster that occurred in the Higashimikawa
area of Aichi Prefecture on June 2, 2023. The total amount of precipitation at AMeDAS Toyohashi
was 418 mm in 24 hours, the largest rainfall in the statistical history. Two rivers overflowed
around 4:30 p.m., causing flood damage in the surrounding areas. In the Yagyu River, water
flowed into an area where the ground level was lower than the surrounding area, resulting in a
maximum inundation depth of 84 cm. In the Umeda River, the maximum inundation depth was
63 cm where the point near the overflow point. The results of the investigation showed the levee
was not damaged, suggesting that the levee had a significant effect in mitigating the damage.
