Unless you are referring to the Great Lakes in the USA, there are no charts nor depth, no any agency doing such mapping. Most lakes here are reservoirs behind dams and the water can vary from week to week. Many here are getting close to zero depth!
Same for rivers, unless they are "navigable" and then they are only channel markers.
But I suspect the problem will not be depth, which is a quite narrow beam, but obstructions not registering on any depth device.
Paul