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navigating inlets

learning by mistakes

"On the afternoon of January 14 at approximately 3:30, the insured was operating in the Boca Raton (Florida) inlet when the loss occurred. When he got to the mouth of the inlet, he decided the conditions were 'excessive' and decided to turn his vessel (23' centre cockpit) around. As he turned, he became caught between two sets of breaking waves and the vessel flipped over in the middle of the inlet. He was able to swim free of the vessel and pull himself out on the jetty. His vessel was pulled out by the outgoing tide and was eventually deposited on the beach next to the jetty.

Welcome to an inlet, one of the inhospitable places where big, big oceans and bays are squeezed through tiny little openings to quiet harbours. This relationship between wide open and narrow, and deep and shallow often results in breaking waves, tricky currents, meandering channels, and dangerous rock jetties.  For a skipper, entering an inlet shouldn't be business as usual. Especially when boats are headed in toward the quiet safety of a harbour a few hundred yards away, there may be a tendency to relax and maybe talk about going ashore, preparing a hot meal, or making a few phone calls. On one claim, for example, the boat's skipper was standing in the companionway, without a life jacket, talking quietly to the helmsman just before dawn, when, according to the helmsman, "...his eyes looked behind me and well above my head. I turned just enough to see this monster wave already lifting the boat rapidly into an almost vertical position and then everything went black."

According to the BOAT/U.S. Marine Insurance claim files, there are four things that a skipper should be wary of when he or she is entering an inlet: breaking waves, shifting channels, crowds, and darkness. Any one of these conditions can make an inlet dangerous; and more than one can make it so treacherous that the inlet should be considered impassable.

Consider it a maxim: Unless you have prior experience, you should enter an inlet that has breaking waves in the channel only as a last resort. Consult your Coastal Pilot, check the fuel gauge, get a weather report and, if possible, head for a safer inlet. You can also drop an anchor or heave-to and wait until the channel is calmer. Most accidents at inlets could have been avoided by simply waiting for conditions to improve. While you're waiting consult your Tidal Current Tables. (Tide Tables can also be used, but high and low water does not always correspond to slack water.) The optimum time to enter an inlet is during slack high water when the channel is deepest and waves are least likely to be breaking. (Slack high water is when the tide is high and current is weak or at zero.) Conversely, waves are most likely to break when tidal currents are ebbing. Also, strong flood tidal currents cause problems for the helmsman, especially if waves continue to break.


This boat was rolled over by a rogue wave while entering Humboldt Bay shortly before dawn. There was one fatality.

Next, study the appropriate chart. Locations and characteristics of lights and markers should be noted, and the courses between them calculated and kept handy for quick reference. It is also wise to have a handbearing compass nearby to note the location of towers, spires, lighthouses, etc., indicated on the chart that could be used to ascertain your position, should a charted buoy be missing or shifted. If waves are breaking, everyone aboard should be on deck and wearing PFD's. Contact the Coast Guard, let them know you are about to enter the inlet, and arrange to contact them again once you are safely through.

Waves generally come in groups of three or more with the largest being the last. Note the distance between waves as well as the time between wave sets. Planing boats may be able to slip through the inlet between wave sets or even between waves by maintaining a comparable speed. If the boat is going too fast, it can climb over the back of a breaking wave and pitch poles or broach. If the boat is going too slow, it can be pooped. One of the crew should be looking aft so the helmsman can concentrate on the channel ahead.

Slower, displacement hull boats stand a greater chance of being overtaken by waves. To avoid broaching-being turned sideways the the wave-a skipper must keep the stern square to the incoming waves. When a wave is passing under the hull, the water will be rushing past the stern toward the bow, as though the boat were backing down. To move the stern to port, the rudder has to be moved to port. On boats with twin screws, increasing power on one engine and backing down with the other will also turn the boat. Another technique is to use a drogue to keep the boat's stern to the sea and then run the engine as fast as possible to maintain steerage. In any case, you can see why handling a boat in a breaking inlet takes experience and should only be attempted when all other possibilities have been eliminated.

If a boat is about to be overtaken by a large, incoming wave in an open inlet, an inexperienced skipper, who doesn't feel confident about his boat handling ability, should consider turning 180 degrees and heading back toward the wave. A boat heading toward a wave is easier to control than a boat being overtaken. This manoeuvre benefits a boat with low freeboard, which stands a better chance of being pooped by a following wave. But if the manoeuvre is initiated too late, the wave will catch the boat broadside and a broach will probably result. Make the turn before the wave reaches the boat, and then keep heading out to sea until all waves in the set have passed.

Inlets are often subjected to strong tides, waves, and currents that can sometimes change the contours of the bottoms overnight, especially in heavy weather when jetties and bridge abutments interrupt the normal flow of water and create silting.

In a recent case that received a lot of publicity, a spanking new 66' sportfisherman ran aground in the middle of the channel at Rudy Inlet in Virginia Beach, VA (BOAT/U.S. Magazine, September 1997). It was winter and the $1.6M yacht (not insured by BOAT/U.S.) was en route from New Jersey to Florida for the Miami Boat Show. Several winter storms had moved sand into the inlet and the boat ran aground in the middle of the channel. Before the yacht could be freed, it was broken up by waves and sank. Claim #9605289.

A few months earlier, a 58' motor yacht almost suffered the same fate when it ran aground further south at Oregon inlet, NC. Again the large yacht had been in the middle of the channel when it struck the bottom. The skipper and his six-year-old son had to be rescued by helicopter. Their boat was eventually freed by a salver, but not before it had been badly damaged by many hours of pounding on the bottom. The skipper later learned that the channel had shifted during Hurricane Bertha and the new channel had not yet been marked.

Both of these incidents could have been avoided had the skippers read the Coast Guard's Local Notice to Mariners and/or consulted the Coast Pilot. If that isn't possible, and you're faced with an unfamiliar inlet, you can try calling the Coast Guard on Channel 16 or 22 or the local TowBOAT/U.S. tower. Mike Quatraro, for example, of TowBOAT/U.S. Sebastian says he gets contacted routinely by boaters who are approaching Sebastian Inlet. Mike knows the inlet well and says he is glad to help. As an alternative, you can try contacting a nearby BOAT/U.S. cooperating marina. Finally, following a local boat (with comparable or greater draft) through an inlet is OK if you're sure it's a local boat. Contact the boat's skipper on your VHF before proceeding.

Many inlets attract crowds of boats heading through the narrow channel to get to open water. At some inlets, such as Port Everglades, FL, small boats share the narrow inlet with giant, ocean-going ships. The crowds on weekends, according to one of the ship pilots in Port Everglades, can be "unbelievable".

Good seamanship and common sense are critical to these inlets. Most skippers know to stay to the right and proceed slowly through the channel to open water. There are always a few boats, however, that go blasting through the inlet with the throttle wide open, despite the other boats, creating a huge wake. There may also be one or two boats on the wrong side of the channel, or the occasional skipper who decides to go fishing, raise the sails, pull a water-skier, or, in the claim below, even "play" in the inlet.

Claim #9609855A. The skipper of a 20' centre console was entering Jupiter inlet in Florida going less than 10mph when he was startled to see a small PWC turn immediately in front of his boat. Waves that day were large, so the skipper had been carefully staying between two swells to avoid being broached. The skipper of the incoming boat was peering straight ahead at the wave when he suddenly saw the PWC. The PWC operator, he said, appeared to be playing in the waves and was even more startled by the encounter than he was. To avoid the PWC, the skipper made a hard turn, which caused his boat to broach in the wave, and his two kids (not wearing life jackets) wound up in the water and had to be rescued by PWCs.

Whenever you're in a narrow fairway, stay to the right, watch your speed (and wake), but be aware that other skippers may not be as conscientious as you are.

Whenever possible, plan to arrive at an unfamiliar inlet during daylight. The more experience a skipper has, the more likely he or she will avoid unfamiliar inlets after dark. Vit Dumas, a legendary sailor and author who spent most of his life at sea in small boats, was especially wary of entering an unfamiliar inlet at night. In his book, Alone Through the Roaring Forties, Dumas wrote that even when sea and wind conditions seemed ideal, he would wait until daylight rather than enter a harbour in the darkness. The reason, he said, was that it was often difficult to distinguish the buoys from the lights on shore.

There have been may examples in the claim files of boats that got in trouble trying to enter an unfamiliar inlet at night. One of the most tragic occurred this past December when a young father, his two sons, and a nephew were killed trying to enter Charleston Harbour late at night. They had left Georgetown, SC about 10pm in 30-knot winds, knowing they would arrive at Charleston sometime during the night.

Apparently, when they tried to enter the inlet, their sailboat was on the wrong side of the jetty, most likely because they were heading for lighted buoys-the wrong buoys-further inside the harbour. The sailboat struck the jetty and the father and his young crew succumbed to the cold water and drowned. Claim #9800043.


This boat slammed into a jetty in Charleston, SC late one winter night. There were several fatalities.

Aside from the problem of light, another hazard in an inlet at night is breaking waves. A 45' sailboat entering California's Humboldt Inlet before dawn on and outgoing tide was between the breakwaters when a "rogue wave" pitch poled the boat and swept one of the crew overboard. (He wasn't wearing a life jacket or safety harness.) The other crew said they could hear him, but in the dark they couldn't see him and he drowned.

The rogue wave was caused when a swell met the outgoing tide, but in the darkness the crew couldn't see the size of the waves that were forming inside the inlet. Had the skipper waited another hour, there would have been sufficient light to see the waves. He should also have called the Coast Guard before proceeding through the inlet. Finally, what should be obvious to anyone who has read the claim files, the shipper should have insisted that everyone on deck be wearing a life jacket. Claim #9408030.