In Paizo's Occult Adventures, the Kineticist class, with a Water Elemental Focus, gets this ability:
Basic Hydrokinesis
Element(s) water; Type utility (Sp); Level 1; Burn 0
You can create water as the cantrip create water, purify water as if using purify food and drink, and dry wet creatures and objects as if using prestidigitation. While you cannot lift water into the air using this ability, you can create mild currents in a body of water by concentrating. These currents are strong enough to run a water mill as if the mill were being turned manually by a creature with a Strength score equal to your Constitution score.
I've done research and discussed with my DM about the part about "mild currents", "water mill", and "turned manually" parts and we can't reach a consensus on how it works. Especially underwater.
Basically, how do you define a Mild current? and how is it even applicable in game?
Edit: Clarification. If possible I kinda would like RPG Stack Exchange consensus on how powerful the mild current would be. (Honestly I just wanted to know if it could make me swim faster in an underwater setting. or maybe make my enemies swim slower.)