I had to turn off the auto filler on my man-made stream due to an early freeze here in NC, but left my Stream Level sensor in place as I figured it wouldn't be affected by a brief freeze. I hadn't counted on the splatter from the waterfall freezing on it, as you can see in the photo below. Even the antenna wire was coated with a thick layer of ice!
Still going strong, however! Not too surprisingly, the signal is a bit attenuated (dropped to -83dbm from normal -78), but still plenty of margin.
Enjoy...
Tom