涌 describes both physical liquid surging and figurative emotions welling up. Often used with directional complements: 涌出 (to gush out), 涌入 (to flood in), 涌上 (to well up).
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A first-tone reading chōng exists only in southern (especially Cantonese) place names, where 涌 names a creek or tidal channel, as in Guangdong's 东涌. For the everyday verb 'to surge / gush' the reading is always yǒng.
Left three-drops water radical, the side-form of 水. It indexes 涌 in the vast water family with 江, 海, 流. It tells you immediately the verb is liquid in nature: gushing, surging, welling up.
Right 甬 supplies the sound yǒng exactly. It originally pictured a hollow bell-handle or covered passage, and the tube imagery dovetails with the meaning: water forcing its way up through a narrow channel. The same phonetic kernel runs through 通, 痛, 桶, 勇.
