Don't!

What drains to waterways? They have left out the subject of the sentence. Typical of authorities such as this: no regard for the English language!

Stuff that you dump! They expect us to complete the sentence. They don't have time to do it. You know how busy they are. Anyway, a curt directive is enough to keep me from dumping my engine oil and old shoes down the drain. Now, I don't know what to do with it. At least this dilemma will keep me from thinking about our hideous election from HELL.

I fall in the middle. I also find these 'drain to waterways' signs to sound somewhat awkward, but they are efficient. Maybe they would be better with a picture of a fish crossed out and "Don't kill"