Sailors often slip by a buoy on their way into a harbor, happy to have it indicating the channel, but without much thought as to how it got there. From their perspective, the employees at several Coast Guard bases around the country see that same buoy and think of it as a livelihoodóand a lot of hard work.
Britannica Online defines a buoy as "a floating object anchored at a definite location to guide or warn mariners, to mark positions of submerged objects, or to moor vessels in lieu of anchoring." But a floating object can range from the size of the rubber ducky in your bathtub to a gigantic sea buoy. There are many different types of buoys in use on the waterways and many are small, unlighted cans and nuns that are relatively easy to moor and handle. The true sea buoys, bell buoys, whistle buoys, and other large lighted buoys, however, are in a different league. Most of us are unlikely to fully comprehend how big these buoys are as our vessels slip past one of these steel hulks.
The standards for buoys are established by the Coast Guard's Office of Aids to Navigation in Washington DC. The Coast Guard, in conjunction with the US Corps of Engineers, determines the places where buoys are to be deployed and specifies what type of buoy should be used in each spot. Once the type of aid to navigation has been determined, an order is placed with a Coast Guard contractor to fabricate that one, specific buoy. A builder in Alabama constructs all the buoys used on the East Coast.
Once the buoy is built, the Coast Guard, an agency of the Department of Transportation, is tasked with deploying and maintaining it for the rest of its life. To understand how that welcoming channel marker came to be bobbing merrily where your light list said it would be, you need to know the story of what the Coast Guard must do to maintain it.
The sheer size of these buoys is masked by the Coast Guardís nomenclature, which refers to them simply as a 9X35, 8X26, or 7X17. But a 9X35 means that the buoy measures nine feet in diameter and 35 feet long. At nearly four stories tall, this is not a small structure in anyoneís mind. When you sail by a 9X35, you are seeing less than half of the buoy, as a nine-foot buoy only has three feet of freeboard. These buoys weigh in at a whopping 18,500 pounds out of the water.
All buoys are held in place with concrete sinkers, called "rocks" by the civilian employees that build them. Different size sinkers are used depending on the buoy size and sea conditions in the area, but dimensions of three feet high and five feet across are typical. The blocks are reinforced with old buoy chain and have a substantial steel bale attached as an eye. A nine-ton, 9X35 buoy would usually be held in place by twin six-and-one-half-ton sinkers using additional tons of chain with diameters as large as 1-7/8 inches.Unless it is hit by a large ship, damaged in some way, or blown off station by a gale, buoys stay on station for six years. At the end of this tour of duty, a Coast Guard Buoy Tender retrieves the buoy, replacing it with a new or refurbished one. The old buoy is transported to a buoy depot that is charged with the maintenance and refurbishment of all aids to navigation.
If you ever get close enough to a buoy to see its six-digit serial number, such as 88-64-19, you can tell the buoy's age by the middle number. The number 64 means that this buoy was manufactured in 1964. Buoys are deployed for as long as 30 years, or five full tours of duty, depending on their condition. There is a standard hull thickness of the steel plate which is used to establish when the buoy is no longer fit for service and must be scrapped.
During the recovery process, the buoy anchors (sinkers or rocks) may or may not be recovered. These large blocks of 3000-psi concrete are often stuck to the seabed and refuse to break loose. If the sinkers can be recovered, they can sometimes be reused depending on their condition.
Immediately after hoisting the buoy aboard the Coast Guard Buoy Tender, the crew scrapes all of the marine growth possible off of the buoy and the sinker while it is still fresh. During the hot summer months, a recently recovered buoy lying in the sun on the deck or a concrete apron ashore can really get ripe if any marine growth is left attached.
The buoy is first sent to a sandblasting facility where all remaining growth and paint are abraded down to white metal. The buoy is then closely inspected by a buoy supervisor to determine if welding repairs are needed to the four basic components of the buoy, the cage, hull, tube, and counterweight. Saltwater has usually taken a toll and some welding repairs are warranted, so most buoys are transferred to the welders. They make the necessary repairs before the buoy is sent back to the sandblasters for a final touch up to the repaired areas.
After all the repairs and preparation are finished, arrangements for painting are made. Due to environmental concerns a few years ago, the Coast Guard switched to an epoxy-coating system that is very durable, but difficult to apply. The buoy is put into a sealed, filtered booth and primer is applied. This is when the system gets complicatedóthe temperature and humidity have to be just right, and once the primer is applied, the painter must put the antifouling layer on when the surface of the primer is at a very specific state of cure. The window of opportunity for applying the antifouling is short, and if the primer is allowed to fully cure, additional coatings will not adhere. The viscosity of the coating is also critical as Coast Guard standards mandate that a minimum thickness of paint be applied before the buoy can be placed on station.
Once the repairs have been completed and the coating applied, the appendages are addressed. For bell buoys, depending on their age, the strikers that sound the bell may need replacement. Gaskets and wiring are renewed, and new lights are also installed. Before the buoy is actually deployed, the crew of the Buoy Tender installs batteries, solar panels, and bird guards.
The average cost of materials to refurbish an 8X26 buoy is $2,134 not including labor, solar panels, wiring, lights, assorted hardware, or transportation. For sound buoys, such as bell or whistle buoys, replacement of the sound device alone can be as high as $4,000. The sea buoy at the entrance to Charleston Harbor, SC, is an 8X26. This buoy, sent new to Group Charleston's Buoy Depot, cost the taxpayers $13,670.The Buoy Department at Group Charleston has one blaster, one painter, two welders, and one electrician who make repairs to all the buoys in their area of responsibility, which is from the North Carolina state line south to Brunswick, GA. In addition, Group Charleston also refurbishes buoys brought from the Caribbean by the Coast Guard Buoy Tender Madrona. This small workforce refurbished 65 buoys last year in addition to being tasked with assorted maintenance jobs to the boats and shoreside facilities. For the crew of the Buoy Tenders, retrieving and deploying a buoy weighing as much as 18,500 pounds offshore with running seas is very dangerous business and requires a great deal of skill. The Coast Guard personnel that deploy and retrieve these buoys demand a lot of respect.
The next time you rely on one of these aids to navigation to guide you safely into the harbor, you might want to think about how much effort and money is involved in keeping it on station for your benefit. Perhaps some of our tax money is wasted, but the federal funds used to support the Coast Guard are well spent to guide marinerís safely home. So, letís hear it for the buoysóand for the boys, of the Coast Guard.