Website design By BotEap.comMany dive sites in popular diving areas have tether balls available for dive boats to use. These mooring balls provide quick and easy access to dive sites and prevent anchoring damage to sometimes sensitive habitats such as coral reefs. However, they require maintenance and are expensive to install, so not all areas where divers go will have mooring systems available. There are several other ways to secure a dive boat above a site depending on the type of dive site, weather conditions, and the type of diving. Traditional anchoring, mooring, and live sailing are the three different types of ways that dive boats stay on station while divers are down.

Website design By BotEap.comMany new boaters greatly underestimate the importance of the correct amount of good 5/16″ chain between the line and the anchor and adequate amounts of line in the anchor locker. The general rule of thumb is that there should be 1′ of chain for every foot of the vessel’s Length Over All (LOA). The chain essentially keeps the anchor more inclined to drag across the sea floor rather than being lifted up at an angle, dramatically increasing the holding power and decreasing the scope needed to hold without dragging.Additionally the nylon line has a certain amount of elasticity which can act as a sort of shock absorber for wave action in rough seas.Ano ther useful tool for divers to utilize when anchored over a site is a “Carolina anchor rig. This rig essentially is a line that begins at the stern of the dive vessel descends to at least 10′ and then runs forward to the anchorline angling deeper and deeper until it attaches at around 20′. This enables divers to de ascend below wave action immediately upon entering the water and provides a line to pull themselves forward should current surface be too challenging or taxing. It also allows divers to spread out as they surface and decompress or complete safety stops. One last hassle saving system is the “anchor ball” retrieve system. Essentially, a large diameter buoy is attached to a steel ring that is placed around the anchor line. When it is time to retrieve the anchor, the boat simply pulls forward 30* or so relative to the anchor and the steel ring pulls the anchor vertically toward the surface as the line passes through it, until the anchor is on the surface and its fins are out of the ring. Now a crew member can simply pull the floating anchor instead of pulling it off the bottom. This is a great system if the dive boat doesn’t have a windlass to do the heavy lifting. The only downside to this retrieval system is that it should not be used if the site is a high relief wreck or reef as the lifting anchor could snag.

Website design By BotEap.comDive boats may want to be anchored so that the boat is directly over the site or the anchor is very close to the site. Anchoring over the site requires a vessel to approach from the direction of the wind/current (generally the same direction in the Gulf of Mexico). When the boat has arrived at the site, the Captain should mark the site with a jar or orient himself via the GPS Chartplotter and then proceed 100′ to 150′ into the wind/current and drop anchor once the engines are off and forward momentum has stopped. As the boat moves astern, the buoy line should be slowly released and some tension applied to prevent the anchor “rig” from entangling itself. Once the anchor has set, more line can be dropped to get closer to the buoy as needed. Divers can now simply jump off the back of the boat and descend through the line of buoys. This method is ideal for large sites that lack updating. The biggest drawback to this style is that divers will lack a sturdy line to hold on to while performing a safety stop and will have to utilize buoyancy control skills while using the line for visual reference only.

Website design By BotEap.comDropping anchor close to the site allows divers to use the anchor line as a strong descent line to the site and back to the dive boat. Adding the Carolina gear is ideal for combating surface current fatigue and reducing divers anxiety by positioning divers below wave action and keeping them away from the bow of the dive boat which can be rocking dangerously (for a surface diver) in significant wave action. To deploy the anchor close to the site, it is easiest to move the motor upwind/current until the desired site shows up clearly on the lower machine and then remove the gear from the boat. As the current pushes the boat back away from the site, the anchor should be dropped shortly after the site is no longer displayed on the lower machine. Now as divers descend to the site it will appear in front of them, and if it is not immediately at anchor it will be a short swim in the same direction forward. This anchoring system is preferred if you must anchor in difficult conditions or strong currents, as divers may not find the anchor before having to ascend. They should surface in front of the boat and the current will simply carry them to the back of the boat. The disadvantage of anchoring with either system is that conditions can change, such as currents or wind changing direction and therefore moving the anchor line and boat relative to the site. Worse yet, sometimes anchors simply drag due to loose sediment or insufficient sediment and the diver may return to where the anchor was only to see a drag line in the sand!

Website design By BotEap.comThe solution to anchor drag is a “connection” system in which the site becomes the anchor. To “moor” a dive boat you need an experienced diver, 10-15′ of chain and an anchor line at least twice the depth of the site with a buoy on the opposite end of the chain. The boat is brought into position on the wreck (again upwind/current) or artificial reef where the chain can be wound around a strong point and tied into a binding knot. The diver submerges, finds the correct tie-off point, and secures the line to the site. At this point, a tug system can be used to tell the auxiliary line that the knot is tied or that the entire line has already been dropped from the dive boat while remaining at a safe distance awaiting the return of the diver to the surface near the buoy. While this system requires an experienced diver who may have to spend some diving time working (someone will have to untie as well) it is the safest way to provide an absolute line to the wreck that will not drag. In strong currents, a Carolina kit can also be applied to this system. Less range is needed for this method of staying over a dive site and multiple boats can be linked to the same wreck at the same time, provided they have properly communicated with each other, whereas you cannot drop anchor at a dive site if the divers are already in the water. This is the method North Gulf dive charters use on popular wrecks to maximize safety and share the sites with others.

Website design By BotEap.comOne last method of putting divers on a site is to not anchor at all, but rather “live boat”. Live navigation is preferred for large sites, drift dives and coral reefs without mooring systems. Essentially, the boat is simply stopped over the site or upstream of the site and divers enter with negative buoyancy and descend in a rapid but controlled manner. A marker buoy may be used as a visual aid for the boat and divers as long as the site is not in danger of being damaged by its heavy weight. Divers may tow a surface flag or carry inflatable surface marker buoys and audible signals such as a storm whistle or dive alert. Divers are free to swim anywhere under this tetherless system, without having to follow a line load. Live navigation is preferred where divers will need to cover a large amount of ground or may have limited bottom time. Diving operations off the SE coast of Florida commonly employ this method due to the high current there. Divers will need to be more proficient in this method and carry more equipment, but will enjoy greater freedom during the dive. The dive boat will need to carefully follow the bubbles and carefully observe the emerging divers.

Website design By BotEap.comIn summary, there are numerous ways to get divers from a dive boat to a site and back. Conditions, the nature of the dive site, and the skill of the divers will ultimately dictate how the vessel should be kept on station.