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It's not on navionics. Here is one that I found. https://www.genesismaps.com/SocialMap/Index
https://webapp.navionics.com/?lang=en#boating@11&key=%7BokiGlbz%7DLI use Navionics all the time. You can move around to whatever waterbody you want to see, zoom in and out, etc. Very handy.
Navionics gives me an idea of the contours. I don't use it to try to navigate to a specific piece of structure. Some bodies of water it is more accurate than others. And, yes, the "Sonar chart" or whatever seems to be more accurate than the base charts. I don't have it on a phone, so I look for contours on the computer and then try to find them on the ice by popping holes and testing with the fishfinder. Kind of a pain sometimes!