Aquatic Propulsion

Jets of water blast from your hands and feet. For as long as you concentrate on this spell: your movement speed increases by 15ft, you can take the Dash Action as a Bonus Action, and attacks of opportunity made against you are made with disadvantage. Additionally, when an attack of opportunity is made against you, you can make a melee spell attack against the assailant. On a hit, you deal 2d4 Cold Damage to them.

At Higher Levels:

The additional movement speed gained by this spell increases by 5ft for every level higher it is casted. Additionally, the damage increases by 1d4 per every level higher the spell is casted. 3rd Level=3d4 Cold Damage, for example.