Hi everyone,One day i was asked to take shots on the Thalweg , This can only be done if you can see it. in my case it was a creek,so i could see it. In other cases this can only be located by soundings, by whatever method you use. mechanical or electronic. So everyone , when and where did you do this, and how, and did you know that this can effect in some cases where the boundary is on a stream or lake and also navigation charts of rivers.and waterways.So with out looking it up ,if you do not know, what do you think it is?