Interesting question, boatclassic.
One way of obtaining an electronic navigation
chart of your local lake would be to make it yourself.
You should be able to do that by converting the appropriate Google Earth satellite
image to the 'BSB KAP' format of electronic navigation charts
. It's not impossible!
Paul Higgins, a CF member
based in Canada
, publishes a Windows program GE2KAP that does the magic. You can read a CF thread about the program at: Google Earth to BSB / KAP
And you can download Paul's GE2KAP program from: DownloadÂ*