noun
inland flooding; flooding inside a levee
Technical term used in disaster prevention and civil engineering. Refers to flooding caused by heavy rain overwhelming drainage systems or surface runoff, as opposed to river overflow (外水氾濫).
See also: 外水氾濫
都市部では内水氾濫が増えている。
Inland flooding is increasing in urban areas.
Inland flooding occurs when rainfall exceeds drainage capacity.