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Don’t Overlook That Can. Or Is It a Nun?

Safe boating is about more than following a line on your GPS. It also requires situational awareness
Navigating safely requires an operator to know more about navigational aids than just red, right, return, especially on unfamiliar waters.

Navigating safely requires an operator to know more about navigational aids than just red, right, return, especially on unfamiliar waters.

In the old days, mariners navigated by looking at a paper chart and a compass. Today, electronic plotters and GPS equipment have just about killed paper charts. But if the electronics fail, many skippers will resort to red, right, return. Keeping the red buoys to starboard when returning to port might get you to your destination, unless of course you skip one, which could lead to a costly mistake.

Stopping by the boatyard one afternoon, I chatted with a boat owner standing by his inboard cruiser in the Travelift and noticed a pair of bent wheels hanging from the propeller shafts. Somewhere in his travels he had found some underwater real estate that mangled the props, and he couldn’t fathom how it had happened. He swore he’d kept the red buoys on his right as he always had in his home waters.

But he was in unfamiliar territory. After coming in from the ocean, he missed the southbound turn that would have put him in the Intracoastal Waterway near
Stuart, Florida. Instead, he followed buoys onto the St. Lucie River, where he encountered two bodies of water with a plethora of aids, some marking the main
thoroughfare, and others marking a secondary channel. Although he did keep red to his right, he managed to miss a small red nun buoy and aimed for a red day marker farther up the channel.

Taking his boat out of the channel for just a few moments at 15 knots was all it took to find the bottom. He was lucky no one was hurt, but his attitude about missing the buoy was rooted in denial. He believed that the buoy was in the wrong place and that the incident was not his fault. But it was his fault, and his failure to observe navigational aids was part of the problem.

Knowing how to read a nautical chart would have helped him too, but when I asked him if he had a paper chart he admitted he only had a plotter. It is easy to assume that a nautical chart is akin to a road map, but there is a difference. Auto maps show readers where to go. Nautical charts show people where to go, too, but they also tell them where they shouldn’t go, like the shoaling water where underwater objects patiently wait to redesign underwater running gear. When I stopped by the boat yard two days later, that boat owner was gone. Hopefully he continued his voyage safely and uneventfully, but I remain amazed by how some people know so little about aids to navigation.

Seasoned mariners may recall a time when green buoys and day markers were black. The decision to change to green came in 1983, and by 1989, when they were all green, it made them easier to see. Floating aids—such as the red nuns with red lights, even numbers and often conical tops, and green cans with green lights, odd numbers and flat tops—are generally anchored to the bottom with heavy chain. They may shift positions with tidal movement, wind and currents. It’s best to keep some distance from them, especially since current or wind can push you into them, in particular at low speeds.

Stationary structures can be day beacons with square boards for green aids, or triangular boards for the red aids. The poles supporting the beacons can be metal pipes or wooden stakes and you should maintain a safe distance from these as well. A rusty pole can leave a mark on your hull, and a snagged fishing line could be trailing in the water and get wrapped around your propeller. Other types of stationary beacons are the range boards that consist of two markers; when aligned, they mark a straight path down a navigable channel.

Specialty buoys are white with orange bands and are used to mark a swimming area or a do-not-enter zone, specify a speed limit, or provide a multitude of other commands the operator must observe. You should also be on the lookout for different markings when approaching a junction in the waterway. Horizontal bands with red over green indicate that the preferred channel is to port. Green over red means the preferred channel is to starboard.

While these aids to navigation are designed to keep the operator in a safe zone, a boater must also practice situational awareness. Noting the numbers on the buoys and checking them against the chart is an important means of verifying your position. If the boater mentioned at the beginning of this column had done so he would have known he wasn’t where he thought he was and probably would not have run aground. Maintaining a speed that allows the operator time to process information is also important. If you don’t have time to check a buoy number against the chart before you spot the next buoy, you’re going too fast.

Buoys may also move. On a northbound delivery in Bogue Sound, North Carolina, I came across a green can marked 3T. It wasn’t on my chart, but when I stopped that afternoon, I met a skipper at the marina who’d touched bottom near that buoy. I explained that the T stood for temporary and that the temporary aid was there because the number 3 buoy was missing. Remember too, just because a chart says a buoy is there, it does not mean it will be there, just like the light on an aid might not be working.

Keep in mind that aids to navigation define channel boundaries. If you maneuver even a slight amount out of the channel, you could run aground. It might not happen at high tide, but low tide could mean a different story. When I navigate a new or unfamiliar waterway, I glance astern to see if my wake is breaking on the channel’s edge. If it is, the water outside the channel is shallow and I may be too close to the edge.

Similarly, if the stern of my boat appears to be crabbing instead of tracking true, there may be strong side current. This can happen on strong flowing rivers or on windy days in wide-open sounds. You may think you are heading straight to the next set of markers, but you could find yourself with your stern out of the channel as you reach a curve or when you need to make a turn. When I hear a skipper complain of running aground in the middle of the channel, I sometimes wonder if that is the cause.

Although shoaling is always a possibility, when navigating your boat pay close attention to the buoys, because close only counts with horseshoes and hand grenades. With that knowledge, proceed accordingly. It’s your boat, skipper. 

This article was originally published in the March 2022 issue.



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