No Google Maps down here: how to find the way underwater?
- Kaja Dańda
- 2 days ago
- 4 min read
Have you ever felt lost underwater? You turn your back towards the wall, you stare into the big blue and… somehow you lose your reference point. You jump in the water for a night dive a bit later than normal and you cannot find the reef. You may get disoriented even on a dive site you’ve logged a thousand times! It doesn’t take much: unexpected current or surge, helping a buddy who cannot equalize… or maybe a very cool squad of squids you decided to follow without realizing how far out you’re swimming…
Having a solid base of underwater navigation skills paired with familiarity of the area you are diving in is crucial to know what to do in case you get disoriented. That is why already on your PADI Open Water Diver course you get to work with a compass and practice basic surface & underwater navigation. With the Advanced Open Water Diver course you step up to the next level: you learn to navigate a more complex pattern and use the natural references as your guide. Let’s talk a bit about the latter!
When diving off the shore or completing navigation dives off the boat, you may need to pay a bit more attention to some distinctive landmarks you’re passing by. Maybe you start right at the pier? Pass by some unique coral or rock formations? Are there any man-made structures underwater that could help you navigate back?
Next time you dive off the shore, look at the sea fans. These soft corals act like natural wind vanes. They grow with their broad, fan-shaped faces positioned perpendicular to the prevailing current to catch passing nutrients. Knowing the local current direction lets you use them as fixed road signs back to shore.
If the bottom where you’re diving is sandy, you have another reliable cue of where the shore might be: sand ripples run parallel to the beach because of the wave action. Most of the time, the depth profile will help you determine if you are coming closer or further away from the shore.
Using sunlight to help underwater navigation is quite advanced and might not work in locations where the sun stays high up in the sky during the time you dive. But in some places and/or at specific times of the year, the sun's rays' direction may help you to find your bearings. And if you are diving off the shore at night: are there any bright lights at the surface that could help you navigate underwater?
Another hint could come from the water movement. Note where the current is going when you start the dive. Has it changed during the time you’re underwater? Is there any surge that could help you determine where the shore is?
Natural references both on the surface and underwater can be really helpful in underwater navigation but if you are diving in a new location, having a compass and knowing how to use it is a must.
Have some patience with the navigation skills! It takes a bit of practice to learn how to use the compass, especially if you are diving in a place with currents. Before heading in the water, practice navigation dry - on the surface, just walking with your compass.
You can improve your navigation techniques by taking an Underwater Navigation course, learn search patterns that call for compass use on a Search & Recovery class or during your Self-Reliant course.
If you decide to go professional and take a Divemaster class, you will definitely practice using a compass during some workshops. You will also use it to prepare a dive site map - usually for the location you dive the most during your training.
To non-divers, a dive map may look like a treasure chart - some reef outline, maybe a sunken boat, depth range and a compass rose. But to a scuba diver listening to a pre-dive briefing or going for a dive off the coast in a new location, a dive map is a critical blueprint for safety, orientation, and navigation.
A good dive map translates the hidden seascape into clear data:
Depth contour: to help you plan and manage your gas consumption
Entry, exit and mooring points: to prevent long surface swims
Alternative exit points: to know where you can leave the water in case if the current picks up and you can’t come back to where you entered
Potential hazards: busy pier, stronger current zone, coral conservation areas
Points of interest and distinctive features you may use for navigation: collapsed pier, concrete blocks, mooring points, buoy lines, as well as unique coral formations, pinnacles, swim throughs, drop offs etc.
Marine life hotspots: cleaning stations, areas where certain species are more common to be found
Good maps should also mention:
Rough distance between the objects on the map
Prevailing current & surge directions
Main compass bearings and sometimes also specific bearings of points of interest
Some of the maps our Divemasters in training made are pretty creative - have a look below! Maybe you even recognize some key features of Villa Blanca shallows - the dive site we use for our shore diving!
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