Oh man... do you really gotta drown 'em??? I mean, if you'd treated your yard for grubs in the first place then they wouldn't be there to eat them. So it's all your fault and the skunk is the one that you want to drown?

Come on, bro, let's give peace a chance... take 'em far, far away and let them roam around eating grubbies in the wild.
If you gotta kill 'em, at least 'eat em. Here's a
link to a few skunk recipes that might help... MMMMMmm - roasted, deep-dried or baked!!! NOM NOM NOM NOM!!!