raubana: I realized much too late that this was not a good spot for a cache, especially for the kind I made. It ended up in a (admittedly obvious) floodplain and also probably a "restricted area", and with access only easily available while the river is partially frozen anyway, it just made sense. Knowing the weather isn't supposed to be getting any colder and how the water level is already rising, I opted to go barefoot in nasty freezing-cold water to retrieve the cache. I think I will move it to another location.