Marine Fuel Spill Prevention Tips 

Every year, countless gallons of marine fuel are spilled into the waters. Unfortunately there are careless boaters out there, and the more marine fuel spills happen, the stricter the boating laws get. 

If you cherish your boating freedom, it’s in your best interest to help prevent marine fuel pollution not only for the sake of the environment, but for the sake of your wallet too, as spilled fuel equals spilled money. Let’s not forget that spilling fuel into the waters is also a federal offense, even if it's unintentional.

Common Causes of Boat Fuel Spills

Fuel Spills at the Pump

One reason boat refueling spills are so common is that unlike the closed fuel system in a car, the fuel tank in a boat is vented, making it easy to overfill it. 

When that happens, bubbles come up through the fuel tank vent and down the side of the boat into the water. A fuel vent surge protector for your boat’s fuel tank vent line helps prevent spills. It alerts you when the tank nears maximum capacity, and helps shut off automatic fuel nozzles before a spill occurs.

Portable Fuel Can Spills

Portable fuel tanks (or jerry cans) are notorious for contributing to aquatic fuel spills. Filling up a jerry can and decanting the fuel from one into a boat’s fuel tank contributes to marine fuel pollution more than you could imagine.

Environmental Protection Agency studies have shown that over 70,000 gallons of fuel is spilled from portable fuel cans alone every year. 

Fuel Spills in the Bilge

Occasional drips of oil from an inboard engine, as well as leaking hydraulic pipes and fuel lines all deposit fuel and oil into the bilge. If these contaminants mix with the bilge water, they’ll eventually be evacuated by the bilge pump out into the water surrounding your boat.

Preventing Fuel Spills When Refueling a Boat

Before Fueling Your Boat

Know the total capacity of your boat’s fuel tank, and estimate how much fuel you need by checking the fuel gauge. Have absorbent pads and a spill kit ready to tackle any spills that might occur from the filler nozzle or fuel tank vent. 

While Fueling Your Boat

Put an absorbent pad or fuel bib around the fuel filler nozzle to catch any fuel splashes. Always hold the fuel filler trigger when refueling, and never rely on the automatic cutoff clip, which can fail. Keep the fuel filler nozzle and the deck fill tube in constant contact with one another to avoid sparks or excess splashing. Refuel the tank slowly, and listen for the sound of the tank approaching its full capacity. 

The U.S. Coast Guard recommends filling a tank to 90% capacity at most to allow for the fuel to expand when it gets warmer without spilling through the fuel vent, so try not to fill it all the way.

After Fueling Your Boat

Clean off any last drops of fuel from the filler nozzle and from your boat with an absorbent pad, then properly dispose of all the pads and bibs you used into hazardous waste containers. If you spilled fuel into the water, try to clean it up with absorbent pads or a marina spill kit. Never use chemicals or detergents to disperse a fuel spill, as doing so is against federal law. Instead, notify the fuel dock staff and the Coast Guard, as required by federal regulations.

Preventing Fuel Spills From the Bilge

Keep inboard motors well maintained, making sure all engine bolts are properly tightened and all oil seals are regularly checked and replaced. Inspect fuel filter couplings, and fuel and hydraulic lines for cracks or leaks, and replace them if necessary. 

Install an oil catch pan beneath an inboard motor, and a bilge sock to absorb any fuel and oil that reaches the bilge water. Bilge pump system maintenance is also recommended to avoid fuel and oil mixing with the bilge water.

Preventing Fuel Spills From Portable Fuel Cans

Only use no-spill portable fuel cans, and have absorbent pads ready to tackle any spills. Fill the fuel cans while on shore on a level surface to reduce spills. The best way to avoid spills in the water is to refuel the boat on land, doing so while it’s level to avoid air pockets forming within the fuel tank that can cause “boat burp” fuel spills. 

Fuel Spills and Federal Law

Once again, creating boat fuel spills is a federal offense, and there are heavy fines in place for those who cause them. Federal law requires any boater to report a fuel spillage (no matter how small) to the U.S. Coast Guard. 

Remember, everybody has a smartphone with a camera these days, so don’t try to cover up or ignore a fuel spill, as failure to report one could land you in a heap of trouble. Using chemicals or detergents to disperse a fuel spill is also a federal offense, so if you cause one, try to clean up or contain it, but never try to cover it up with harmful chemicals.