Local Notice To Mariners: A Reality Check For Your Charts

Did you know that right now, as you read this, there are at least 40 navigation buoys between Eastport, Maine, and Shrewsbury, New Jersey, that are missing? They just aren’t there. Oh, you’ll see them on the charts, but not in real life. There are about 109 buoys in that same part of the country that are “off station.” They are there, but they are not exactly where they are supposed to be. Put another way, red buoy “2” may be on the right when you return, but you won’t necessarily be in the channel.

Maybe you don’t do your boating in the Northeast. Well, if you are anywhere south of Little River, South Carolina, and the US Virgin Islands, there are over 700 U.S. Coast Guard navigation aids that are missing, off station or otherwise destroyed. If you are surprised by these numbers, then you probably haven’t spent a lot of time reading your weekly Local Notice to Mariners (LNMs). It’s the U.S. Coast Guard’s published document listing everything that is wrong with or missing from your charts that might get you in trouble.

Things happen to navigation aids out there. Storms damage them, vessels bump into them, lights burn out and things just generally break. When they do, boaters of all stripes report these things (like all good mariners do) to the U.S. Coast Guard. And while they work hard to fix them as soon as possible, keeping up with the carnage is a constant battle.

LNMs are published weekly by the nine Coast Guard districts and provide mariners with a complete list of everything to watch out for within the district boundaries. These LNMs are must-read resources for all of us. You should download the LNM for your boating area before you head out next time and update your charts and local knowledge accordingly.

Of course, most of us use electronic charts. As long as you keep up with weekly updates, the location and condition of any navigation aids (critical updates), and even hydrographic surveys and shoreline data, will be correct. However, updated charts — electronic or paper — will not include all of the safety information listed in an LNM (such as Special and Advanced notices), so you should still review the latest notice before heading out.

The basic makeup of the notices is consistent throughout the country. They start with some general housekeeping and contact information, and then clear up the acronyms used in the pages below. The sections below the acronyms dig into the heavy stuff.

Section I

This section of each notice contains Special Notices — the things that are of “special” concern to the mariner. If you are boating in Hawaii, that means letting you know about hazards associated with the Kamokuna Lava Delta. These include “explosions of large chunks of hot rock and debris, hot lava arching out, the release of toxic gases and collapse of the lava delta.” The dangers associated with a lava delta collapse are “fiery explosions, large waves and towering plumes of steam and that ash can extend up to or out 300 meters.” Yikes.

So, if you see lava entering the ocean, the 13th Coast Guard District (and your mother) would like it if you stay at least 300 meters away. Good tip.

Other things listed in Section 1 of a LNM includes Naval exercise areas to avoid, dredging operations and any other things not normally expected in your waters that are hazards this week. Read Section 1 thoroughly each week; that’s my advice.

Section II

This section of each LNM lists Discrepancies. This section lists all reported and corrected discrepancies related to Aids to Navigation (ATON) within the District’s boundaries. These are changes in the status of an ATON that differs from what is published or charted. In some districts this list is fairly short. Hawaii (Coast Guard District 13) is a good example. In others, such as Coast Guard District 7, it’s many pages long.

Discrepancies are listed by Light List Number, but each one includes the associated chart number. Simply search the LNM for your chart number, and then make corrections to your chart accordingly. So, if you boat in South Carolina, you’ll want to note on Chart 11532 that the Winyah Bay Range C Rear Light is listed as “STRUCT DEST” (structure destroyed). The severe shoaling in Winyah Bay, listed in Section I of the LNM, may keep you out of there anyway.

Section III and IV

These sections generally work together. Section III lists Temporary Changes. These are temporary (intentional) changes to the ATONs in the area. And when charted aids are temporarily relocated for dredging, testing, evaluation or marking an obstruction, a temporary correction will be listed in Section IV (Chart Corrections) and provide the new position. Again, all changes in both sections are referenced by their chart number, so you can easily find the changes and make corrections to your specific charts.

Section V

Section V is for any Advanced Notices. This section contains advance notice of approved projects, changes to ATONs, or upcoming temporary changes, such as dredging. Again, they are categorized by chart number, so have a look through this section to learn about changes and operations that may affect your boating.

Sections VI, VII and VIII

These sections list proposed changes to the waterway, general information and corrections to the Light List. But if you have done your homework on the Sections I through IV, you have made great gains in giving your charts — as well as your local knowledge — the updates they need to be accurate and useful.

And don’t worry about those missing buoys too much, the U.S. Coast Guard’s ATON Fleet is on it; they just want you to know what is on their list of things to fix. You can stay updated by downloading the LNMs.