Charts have errors whether it is a result of survey errors or source errors. This applies to ALL charts, whether government or private, official or otherwise. The common rules of navigation require that skippers, in addition to official charts, use multiple sources of information, including sailing directions, cruising guides, radar, sonar, local diligence, and good eyesight. With the best chart in the world, one should never get close to coral reefs at full speed and at night, but rather when the sun is highest, at very slow speed, and with a person on watch on the bow. This is the only way to ensure that breaking waves be spotted from a distance, and that possible uncharted coral heads be avoided.
The warnings that go with all charts are not there to protect the chart makers, but rather to protect the chart users from making mistakes in over-reliance on any one tool of navigation.
Cruisers can add their anchorages to the Navionics Community.