Hull Cleaning

Cleaning the hull of a vessel is essential if it is left in-water. Marine life will begin to grow on the vessels hull and underwater components. This will result in increased fuel consumption, a reduction in overall power and performance, a reduction in heating and cooling system efficiency, and faulty or erratic instrumentation readings. Anti-fouling paint is used to inhibit marine growth on the hull and running gear but is limited by the amount of vessel movement, the speed at which the vessel travels through the water, the amount of biocides in the anti-fouling paint, and the location at which the vessel resides.

Marine growth usually begins as soft slime and algae-type grass on the vessels hull, followed by hard calcareous barnacles on the running gear. Non-commercial vessels which reside in Hampton Roads, Virginia begin to typically form a one-half inch layer of slime on the hull and barnacles approximately three-quarter inches in diameter in two to four weeks in the summer months. We recommend for most operators to have their vessels cleaned on a routine monthly maintenance schedule from March through November with a mid-winter service in January. Growth slows significantly during the winter months but it doesn’t stop. We do not recommend discontinued service throughout the entire winter. The amount of growth which would accumulate over a four to five month period would have to be scrubbed aggressively by a diver to clean the surfaces effectively.

Our practice is to utilize the least aggressive means necessary to effectively remove the marine fouling from the vessel. The more aggressive a diver is while servicing a vessel, the more anti-fouling paint is scrubbed off in the process. This will result in a higher concentration of marine growth to remove during the next service and shorten the life of the current bottom paint system.

We utilize a wide variety of cleaning tools ranging from a simple sponge to hydraulically-powered hull scrubbers.

Zinc Replacement

Two occurrences to be concerned with when metals are placed in water are Galvanic Corrosion and Electrolysis.

Galvanic Corrosion occurs when two dissimilar metals in contact with each other are placed in an electrolytic solution (i.e. saltwater) and form a natural battery. This will cause ions to transfer from one of the metals to the other. This corrosive exchange will weaken the metals and create irregular surfaces (pitting).

Electrolysis is the other phenomenon which occurs that can have a deleterious effect on underwater metal components. It is usually the more significant of the two. It can lead to pitting and corrosion of any metal, under certain conditions. Like Galvanic Corrosion, Electrolysis also occurs when electrons (ions) of dissimilar metals are exchanged in an electrolytic solution (i.e. saltwater). However, this phenomenon is induced by stray currents or electrical currents not following their anticipated path. The rate of electrolysis is usually much higher than that of galvanic corrosion.

When propellers, rudders, shafts, nuts, trim tabs, etc. are placed in saltwater, they will begin to corrode by either or both of these processes if not protected. Zincs installed on a vessel are considered “Sacrificial Anodes”. This is because they will sacrifice themselves (deplete / corrode) over time in order to protect other underwater metal components. Zinc is a metal which is less noble than other metals like brass. Therefore, when placed in electrical contact with a more noble metal, it will act as an anode, and give up its ions more readily than the metal it is in contact with.

Frequent zinc inspections are necessary to determine if replacement is required in order to keep the vessels components from depleting or corroding themselves. If replacement is required, Dockside Diving can supply zincs from our inventory and transport the old zincs to a recycling facility.

Propeller Removal / Installation

In the event of propeller damage caused by the vessel hitting a subsurface object or running aground, propeller repairs may be required. Propeller work may also be desired to help your vessel achieve optimum efficiency by adjusting the diameter, pitch, or number of propeller blades. Dockside Diving has the tooling and expertise to remove and install propellers in the water without the need for a vessel haul-out. Our team can ascertain the damage, perform the removal of the propellers, transport the propellers to a repair facility, pickup the propellers from the repair facility, and reinstall the propellers in a timely manner to help the vessel operator meet their time constraints.

Search and Recovery

Dockside Diving has the capacity to perform all light and medium duty search and recovery operations. We are equipped with several thousand pounds of lift bags and rigging gear for buoyancy and high flow water pumps to keep objects afloat once on the surface. Some of our recovery capabilities include but are not limited to: Lost jewelry and personal items, sunken vessels, sunken automobiles, and sunken building structures.

Underwater Inspections / Photography / Video Recording

Underwater inspections, photos, and video are often utilized for documentation and insurance purposes. Dockside Diving can perform underwater inspections and provide written reports of our findings. We can also take underwater digital still photographs, record standard-definition live video with monitoring available on the surface, and record high-definition video which can be recorded on a CD or DVD.