Monks who chose to follow the Way of the Torrent spend much of their time contemplating water in all its forms.  They teach that a tranquil mind and spirit can harness this primordial force to defend themselves, move through or on the surface of water with ease, and even unleash its fury.

Flowing Water Technique

When you use Patient Defense, you may add your proficiency bonus to your AC for any attack you can perceive.

In addition, if an attacker misses a melee attack against you while you are using Patient Defense, you may spend 1 additional Ki point to use your reaction to counter with an unarmed strike. If you hit with your strike, you may choose to knock the attacker prone (DEX save to avoid) or move the attacker up to 10 ft in any direction (STR save to resist).

Deep Sea Armor

At 6th level, you gain the ability to channel your ki into into a layer of cold energy to protect yourself. As a bonus action, you can spend 2 ki points to cast the spell armor of agathys.  You require no material components to cast this spell.

You can spend additional ki points to cast armor of agathys as a higher-level spell. Each additional ki point you spend increases the spell’s level by 1. The maximum number of ki points (2 plus any additional points) that you can spend on the spell equals half your monk level.

Water Striding

At 11th level, you gain a swim speed equal to your walking speed. In addition, you may spend 2 Ki to cast water breathing on yourself. You require no material components to cast this spell.

You may spend a reaction and 1 Ki to gain the ability to treat the surface of water as if it were solid ground and even end your turn while standing on the water. This effect lasts for 1 minute but does not require concentration.

Swirling Vortex Strike

At 17th level, you gain the ability to summon the power of the raging sea into a series of unarmed strikes in a 10 ft radius around you by expending 6 Ki points. All creatures chosen by you in the affected area must make a DEX saving throw or be knocked prone, have their movement reduced by 10 ft until the start of your next turn, and suffer 4d10 Cold and 4d10 Bludgeoning damage. On a successful save, the target(s) take(s) half damage and is/are not knocked prone or suffer reduced speed.