Los Angeles County Measure W is a parcel tax to pay for cleaning up stormwater — the dirty runoff created when rain hits the streets and other paved surfaces, picks up toxic urban gunk and carries it downstream to foul the beaches and pollute the ocean. Depending on how you look at it, the measure is either a hard but necessary pill to swallow or an exciting step into the future. In either case, it’s the right move, and The Times urges voters to say yes.