Hello everyone, I was wondering where you guys get your shapefiles for bathymetry from? I need contour depth lines for US lakes, but can only find two main sources; one for Texas lakes and one for Oklahoma lakes via their water board websites, twdb.texas.gov and owrb.ok.gov respectively. Do you know of other sources for other states or a national dataset? If they are not made available publicly, are their sites where we can purchase the raw data? We've tried a few mapping companies without success. We need contour depth bathymetry on our lake maps and keep hitting walls finding them. Any help would be greatly appreciated. Thank you!