clear water swirled with sepia
sticking to a sandy, squared floor
so sloppy, slippery.
that old winter water on wet winter days.
Love the alliteration!
This manages to communicate what winter is like even to those who don't have snow and ice. I grew up in LA, and can remember what it's like not to have winter. The sounds of the words, especially the last line, are very evocative of what you're describing. I like it, it's simple and elegant.