KanjiJLPT N1
Overflow

overflow, inundate, spill

Mnemonic

A violent storm unleashes torrential rain on the reservoir built to benefit the entire valley. The water level climbs higher and higher until it hits the tipping point—a catastrophic overflow sends waves crashing over the dam, turning the town's greatest benefit into a raging flood.
Additional thoughts
Visualize dark storm clouds pouring rain into an already-full reservoir. The dam was supposed to benefit the people, but too much storm means the water overflows destructively. Storm plus benefit equals overflow.
Quick recall
A storm fills the reservoir meant to benefit the valley until it overflows the dam.

Details

The keyword for 溢 is overflow. This kanji refers to the act of liquid spilling over the brim of a container, exceeding its capacity and flowing out beyond its boundaries. It can also be used figuratively to describe an abundance or excess of something, such as emotions or energy, that cannot be contained. The sense conveyed is one of fullness reaching a tipping point where what is held inside inevitably pours out.
On'yomi
いつ
Kun'yomi
こぼ.れる、あふ.れる、み.ちる