Boaters, perhaps more than any other group, see the impact of land-based activities on estuarine and marine ecosystems. From shrinking habitats and prop-scarred seagrasses to dead and dying birds trapped in monofilament line, human impact on the marine environment is not always a pretty sight.

But while boaters are a relatively small part of the problem, they can play a large role in the solution, says novelist and boater Clyde W. Ford, whose most recent non-fiction work covers everything from fuel to cleaning fluids in a step-by-step guide to making every boat more environmentally sound.

Boat Green: 50 Steps Boaters Can Take to Save Our Waters (2008, New Society Publishers, 244 pages, $17.95) starts with the basics – obeying current laws on reporting fuel or oil spills, dumping raw sewage and throwing trash overboard.

From there, Ford covers an array of options for boaters from biofuels and solar energy to cleaning supplies in a book that every boater concerned about marine ecosystems should read.

In most cases, he clearly delineates the advantages and drawbacks of each option. Biodiesel, for instance, is nontoxic, biodegradable and safer to store than regular diesel, but not always easily available. Ford recommends that boaters initially switch to B20 – 20% biodiesel – rather than a 100% renewable mix. That blend can safely be used with any petroleum product already in your tank, and will generally improve engine performance.

On the other hand, Ford is more concerned about the long-term problems caused by ethanol, beginning with the net impact of producing it and then focusing on specific on-board issues. “Ethanol is a solvent that will loosen varnish, rust and particulate matter in the fuel tank, injectors, carburetors and within the engine, sending sludge throughout the fuel system,” he writes. “It can also attack the resins in fiberglass fuel tanks causing them to fail. The alcohol in ethanol can dry out gaskets, seals and hoses, causing fuel leakage.”

The net environmental impact of ethanol in boat fuel, particularly if fiberglass tanks fail, is likely to be negative. Ford recommends that boaters “ask before you pump” to ensure that gasoline is ethanol-free.

New Options in Engines

The traditional two-stroke outboard engine – known for its stinky smoke – is no longer available, thanks to 1998 regulations that stipulated a 75% reduction in emissions. That change created new types of outboard motors, each with its own advantages and disadvantages for speed, fuel efficiency, cost and environmental impact. Ford clearly outlines the benefits and drawbacks without calling a favorite.

Boats with inboard power trains also are covered, with a focus on hybrid diesel-electric propulsion units that are now available at prices comparable to traditional diesel engines. A diesel generator in a hybrid propulsion system is more efficient than a stand-alone unit because it runs at a given RPM with a balanced load to make electricity, he notes.

Wind and solar power alternatives also are improving from their traditional use as trickle-chargers for batteries and some new systems make it possible to power boats with solar alone. Ford walks readers through installing solar systems, from photovoltaic anchor lights to simple hot water heaters. The book also takes a look at options in wind power, including newer wind turbines or towed generators. He also offers a couple of caveats: be sure a wind turbine is high enough to stay out of the way of your crew and equipment, but not so high or so heavy that it compromises the stability of your vessel. If you chose a towed generator, watch out for sharks. They’ve been known to eat them!

Along with fuel, boaters can impact marine environments with human waste and gray water. In fact, according to the US Environmental Protection Agency, one weekend boater’s discharge of untreated sewage is equal to the treated sewage of 10,000 people. Ford details the hows and whys of managing waste from new technologies like composting toilets (totally different from their land-based brethren) to more basic steps like identifying nearby pump-out stations and using them.

Small Steps Make Big Differences

While much of Boat Green considers options for new equipment, separate sections on operating and maintaining a boat look at ways boaters can make a difference every day.

• Implement a zero-spill policy for oil changes.
• Most antifreeze is highly toxic and can kill marine organisms by lowering levels of oxygen in the water as it biodegrades. A less toxic alternative is made with propylene glycol but even that may contain high levels of heavy metals leached from engine surfaces. All antifreeze should be recycled not disposed of.
• While most batteries are already recycled, good maintenance practices can keep them running longer.
• Prevent pollution with diverter valves, bilge socks and oil-eating bacteria.
• A crankcase ventilation system captures blow-by gases, reducing oil mist by up to 99% and limiting oil in bilge water discharges.
• Select a non-toxic bottom paint and use dustless or vacuum sanders to remove paint. Take a tip from the old-timers and add a half-cup of cayenne pepper to a gallon of antifouling paint.
• Use non-toxic cleaning products, including more tips from old-timers like baking soda instead of scouring powders and vinegar instead of window cleaners.
• Make sure your marina or boatyard complies with good environmental practices including dedicated work areas over non-porous surfaces.

Well-maintained engines use less fuel and are less likely to leak or emit harmful substances, and Ford’s most important advice may be exactly what every boater wants to hear: “Use your boat often – they run best when they’re run regularly.”