Game Mechanics: Quad Spell not landing when near water

[Thepen]

I've recently been quadding near a water line and noticed that if the mob your targeting has any part of his body in water, and you're 100% out of water, the spell will not land, but will cast and remove mana.

For example:

I'm standing on land, without levitate. I begin casting my spell and right as it lands, the mob I have on target has a foot or a toe touching water. The spell will cast, but do no damage.

This is not to be confused with me levitating over water while the mobs are 100% under water. The spell wont cast in that situation.

I'm a 54 druid using Lightning Blast and Ensnare to Quad.