Open Source Nautical Charts


I am becoming interested in open source nautical charts. I know that Open Sea Maps are one of them. Does anybody here have any other open source nautical charts that they use?

ENC charts from NOAA

NOAA provides ENC electronic chart downloads for free and they are updated weekly. The updates are a key feature - they can save your life! Inland waters are not included in NOAA charts.

For inland waters, ENC charts are provided by the Army Corps of Engineers:

Navigation software is required that can run ENC charts. There is also free viewer software that doesn't navigate.

OpenCPN is recommended free nav software. It runs on a Windows laptop:

how i used eNC charts

I used ENC charts by running navigation software on my home Windows computer. I charted courses to all the destinations planned. Multiple waypoints were charted for changes of course due to obstacles. All these waypoints were 50 feet away on the safe side of a buoy.

The waypoints were all saved in the ENC nav software and exported in a text file to my Garmin GPS 76. Each waypoint had a name but the length of the text string was limited. I kept a paper list of waypoints and their coordinates.

The GPS 76 is no longer available, but it is similar to today's GPS 73. It is not a chartplotter - there is no chart.

On the water, in the GPS, display the alphabetical list of waypoints, highlight one, and press Go To. It displays the distance and compass bearing. While underway it displays the track deviation. When near the waypoint the GPS gives an audio alert.

Why the GPS 76? In a small sail or power boat (28 feet) the helm position is likely to be wet. The GPS 76 is waterproof.

In a larger boat, run the ENC nav software on a ruggedized laptop. The chart is displayed. Then you have a chartplotter with free charts.