What are the poles on Jersey’s fire hydrants?

If you're like me, you've noticed the new look of New Jersey's fire hydrants and wondered what it's about. I'm talking about the thin poles affixed to the sides of hydrants. They stick straight up in the air like an antenna, often silver with a stripe of blue in the middle. Can we get a confirmation in the comment section below from a professional or volunteer firefighter of what these are for?

My guess is they're simply a marker for times of deep snow, or also overgrown vegetation, so emergency crews can easily locate the hydrant. Or is there some higher tech function of these things? I'm curious because I've only seen these in the last few years.

If you have an answer to this, please let me know in the comment section below.