This rare kanji has no clear standalone meaning. Treat its meaning as uncertain.
潗 combines 氵 (water) with 集, which likely contributes the sound. The exact historical development is uncertain.
Water 氵 gathering 集 together, like a spring welling up. This fits the kun reading わく (to well up).
For シュウ, imagine water gathering into a shoe: shoe -> シュウ, and the water wells up inside.