Clean Boating

by Susan Granato, ABA Boating Safety and Environmental Liaison

Recreational boating is a fun and exciting part of most of our lives. Whether we are fishing, water-skiing or just cruising around, being on and around the water is both memorable and enjoyable. As boaters we need to practice good stewardship to preserve the waterways that have so greatly enhanced our lives. Boat operation can have a number of adverse effects on ecosystems in and around our cherished waterways. Engine emissions, wake effects, propeller contact, and noise are unavoidable aspects of motorboat operation. Responsible boaters should understand the simple steps necessary to minimize the adverse effects of motorboat operation.

Engine emissions are the fluids and gasses exhausted to the air and water during motorboat operation. Exhaust to the air increases air pollution and smog readings in sensitive areas. Boats can have a disproportionate impact on air pollution. For example, a personal watercraft (or jet ski) will emit the same amount of pollution in seven hours of operation as a new passenger car will emit when driven over 100,000 miles. Engine emissions to the water can affect water quality, sediment quality, and can enter the food chain. Many fuel related pollutants are highly toxic and can persist in fatty tissues of shellfish, crustaceans, fish, and birds that feed in the aquatic environment. Currently, most personal watercraft and outboard motors utilize the "two stroke" engine design. These engines are designed to be both compact and powerful. Unfortunately, this type of engine burns gasoline inefficiently, as much as 30% (or 2-3 gallons an hour) of the gasoline is discharged into the environment unburned. This problem causes both air and water pollution.

As a responsible boater there are a number of steps you can take to help reduce the impact on the environment. All boaters can minimize engine emissions by keeping their engine properly tuned and by following manufacturers specifications for fuel mixtures and maintenance schedules. When buying new engines look for more efficient engines that exhaust less fuel and combustion byproducts. For example, newer high performance four stroke engines and two stroke engines with direct injection greatly reduce air and water pollution while offering improved fuel economy, lower oil consumption, and improved idle performance.

Wake effects are the turbulence caused by the hull and the propellers moving through the water. Wake effects can stir up sediments in shallow areas and erode the shoreline when waves from one or more boats impact the shore.  When sediments are mixed with the water, fish suffer from abrasions on gill surfaces, and nutrients and other sediment-associated pollutants are mobilized. When nutrients are mobilized, resultant algal blooms can further degrade local water quality.

There are a number of simple steps the responsible boater may take to minimize the wake effects. Boaters should treat all areas within 100 feet of the shoreline and (or) water depths less than 10 feet as no-wake buffer zones. Boaters should treat all areas within 300 feet of nesting or foraging sites for water fowl as no wake zones. Respecting aquatic wildlife and fishing areas is good for the environment. Recognizing these areas as no wake zones is also good for boat safety because these areas also may contain obstacles and debris that would do damage at high speeds.

Practicing good stewardship is simple and may have lasting effects on the aquatic ecosystems we enjoy. The environmental stewardship practices that reduce the effect of motorboat operation on the environment also are economical and safe boating practices. Valuable resources can be preserved one boater at a time.

To read how propeller contact and noise effect the environment, please visit the "Clean Boating" section of www.americanboating.org.