Understand NOAA Marine Chart and Channel Marker Coverage

Where coverage is available

MarinePath shows NOAA marine overlays and channel markers where NOAA provides coverage in U.S. waters. Coverage is regional, not worldwide. You can explore marine maps on Apple Watch and iPhone.

Map views on iPhone

On iPhone, choose Apple Maps with optional NOAA marine overlays where available, or satellite imagery. A satellite image is not an official nautical chart. The supplied screenshots illustrate different map views and recorded tracks.

Charted water depths

Turn on Water Depths in Map Layers on iPhone or Apple Watch to display numeric soundings where available. Depths are off by default. Choose feet or meters in the device’s Units settings. On iPhone, depths work with Standard and Satellite maps independently of Marine Detail. These are charted soundings, not live water levels; missing labels do not indicate safe water.

When charts or markers are missing

Check your internet connection if map tiles do not load, and use Retry when shown. Outside NOAA coverage, base maps, waypoints, and recording remain available. On iPhone, Settings > Advanced > Clear Map Cache removes downloaded tiles so they can be fetched again. Clearing the cache does not add coverage where NOAA has none, and it does not delete saved sessions.

Coverage and safe navigation

Missing chart coverage does not mean an area is safe. MarinePath is not certified for navigation; NOAA Chart Display Service content is not certified for navigation. Use official charts, approved navigation equipment, and safe on-water judgment.

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