Beware inaccurate Navionics charts of Medway

Navionics Saltpan Reach

Click for larger image, (c) Navionics Inc

If you use the popular Navionics charts on your chart plotter, iPad, smartphone or web app (see for yourself here) you may notice highly inaccurate depths and spurious features such as non-existent rocks and buoys. This refers to their “normal” cartography, not the “sonar” version which is crowd-sourced from user-supplied depths and shows even more bizarre contours. The example above shows Saltpan Reach on the Medway, close to the container terminal and the LNG terminal, an area frequently surveyed by the port authority, which supplies its data to UKHO. In addition to the three non-existent mooring buoys (circled), there is a non-existent drying patch just off Sharp Ness (labelled “Sharp Point”) and a large area incorrectly shown as very shallow (shown blue) just north of Burntwick Island. Around the high water mark in the adjacent creeks and the Swale numerous spurious “rocks” are shown. Similar inaccuracies in Navionics charts have been reported in the Solent and St Vaast areas. Read more…

UPDATE: The specific errors shown above have been reported to Navionics and have been corrected, though the spurious rocks litter the foreshore… Still no explanation has been forthcoming.

Leave a Reply

Your email address will not be published. Required fields are marked *