What the Helen of Troy is This

Speaking of Weird, What the Helen of Troy is Up with all the Sand Piles?

“Dear PoPville,

These piles of sand appeared a few weeks ago on the sidewalk on my street (New Hampshire Avenue) in Columbia Heights. I think they have appeared in previous years as well. Any idea where they come from??”

Anyone else seeing random piles of sand around town. Anyone know why?!?! (Wrong answers only.) No. I will also accept right answers, I’ve just always wanted to try out a wrong answers only post. But I guess that’s basically a caption contest!! Anyway, what the hell?