Sun up and sun down, assuming you mean the catwalk lights.
"They run off of a photo eye, so they come on and off automatically at dusk and dawn," explained Dan Vivian, the facilities manager for the City of Grand Haven.
To see the previous question on the catwalk lights answered two weeks ago, with some background on them, CLICK HERE.
Do you have a question for the Tribune? E-mail it to email@example.com, and type MAILBAG in the subject line. Or mail it the old-fashioned way to: Grand Haven Tribune, MAILBAG, 101 N. Third St., Grand Haven, MI 49417. We'll do our best to get you an answer! A new Mailbag appears on grandhaventribune.com at 5 p.m. Mondays, Wednesdays and Fridays.