As if saltwater is not harsh enough on a boat, factor in barnacles. Barnacles are found in the coastal waters of Georgia, South Carolina, North Carolina, and beyond. If you have peered into saltwater around docks and pilings, you have more than likely seen a barnicle. For boaters, barnacles can become a nuisance. What are the effects of barnacles on your boat?

Why Do Barnacles Grow On Boats

Much like a seawall, buoy, piling, or dock, objects that remain stationary at times are prone to the accumulation of barnacles which is why they grow beneath the waterline on boats. The barnacle will affix themselves to almost anything and rapidly grow entirely, covering the object. 

What Are The Effects of Barnacles on Boats

Barnacles can affect boats in a multitude of ways. Each can result in spending excessive amounts of money on repairs and or operating costs. 


One of the most costly circumstances of accumulating barnacles on the hull of a boat is increased fuel cost.

As barnacles begin to layer the bottom of the boat, the hull’s design to limit drag is all but eliminated.  Once barnacles have grown, the craft will not cut through the water easily, thus increasing the amount of fuel burned. 

Fuel operating costs of a cleaned boat hull versus a fouled boat hull are substantially different. The effects on the wallet will be felt every trip until the barnacles are removed. 


We all know that whatever type of gasoline or diesel engine the boat is fitted with requires water from the sea to be pumped through it to remain within safe operating temperatures.

The raw water intakes beneath the surface of the water can become fouled with barnacles. As a result of fouling, water flow to the engine can be significantly reduced or eliminated. 

An engine that becomes overheated can put you and your passengers at risk should the motor shut down completely. Beyond safety, repairs to an engine that has overheated is a costly and avoidable situation. 

Weight and Drag

Many would say that weight and drag would fall under compromising fuel costs. Although it does directly affect fuel costs, the implications of weight and drag go further. 

A direct effect of additional weight or increased drag is a loss of speed. The boat may not respond quickly in its ability to get on plane. Optimal cruising speed to maximize fuel efficiency will be altered, and the ability to pull someone up on skis when participating in water sports. 

How To Reduce the Growth of Barnacles On Your Boat

The ability to keep a boat operating at maximum efficiency when barnacles are a threat is simple. Following a few steps will keep the hull clean. 

Antifouling Paint

If you plan to store your boat in the harsh saltwater environment, you need to invest in antifouling paint. 

Bottom paint contains biocides that are slowly released to help prevent barnacles from settling on the hull.  Boat service yards will apply bottom paint to your boat at a price per foot. The coating should be inspected and reapplied as necessary. 

Storing a Boat Out of The Water

Some would argue that the application of bottom paint reduces the value of the boat. To avoid painting the hull in an antifouling coating, consider storing the boat out of the water. 

A few options include keeping the craft on a trailer, dry rack storage, or even more convenient, a drive-on floating boat lift. The drive-on boat lift can be kept at a dock to utilize the boat without the hassle of launching it. 

Bottom Cleanings

Antifouling paint does an excellent job of reducing barnacles’ growth but does not eliminate them entirely.

When a boat is stored in saltwater, even with a biocide applied, divers must come periodically to scrape the barnicle away from the boat’s hull. The frequency depends on your area’s growth rate but should be done atleast once per year and particularly during the summer months when the barnacles multiply rapidly. 

Ask around for a local diver who is trusted. Neighboring boat owners will be glad to steer you in the right direction.

It’s Time to Start Removing Barnacles to Lower Costs

Yes, money will need to be forked out to help prevent or remove barnacles periodically. The combination of bottom paint and hull cleanings will reduce having to pay higher fuel costs and possibly engine repairs due to overheating. The upfront cost will help lower expenditures caused by excessive barnacle growth on the hull of your boat.