Conventional carbureted 2-stroke outboard motorboat engines allow as much as 20-30 percent of the fuel used to pass directly to the air or water, releasing toxic and carcinogenic materials to the environment. Working with industry to address this problem, the U.S. Environmental Protection Agency (EPA) developed regulations in 1996 that will result in a 75 percent reduction of hydrocarbon emissions by 2025 from spark-ignition gasoline marine engines (including outboard engines, Personal Watercraft engines, and jet boat engines). As a result, today's 4-stroke and Direct Fuel Injection 2-stroke engines are substantially cleaner, reducing fuel costs for the boater and protecting the environment.

The following links provide additional information on outboard motorboat engines and the environment.

Environmental Impacts of Conventional Engines and Benefits of New Technologies

• Better Boating through Environmental Engines, an article adapted from the Massachusetts Office of Coastal Zone Management’s (CZM) Coastlines newsletter - http://www.mass.gov/czm/boatengines.htm.
• The Scoop on Boat Engines, also adapted from CZM’s Coastlines newsletter - http://www.mass.gov/czm/boatenginescoop.htm.
• Overview of EPA’s Emission Standards for Marine Engines (PDF, 183 KB), an EPA fact sheet.
• Do Motorboat Engines Cause Water Pollution?, a page of the EPA Region 1 Web site - http://www.epa.gov/NE/assistance/cmei/index.html.
• Preventing Boat Engine Pollution, a brochure produced by the Rhode Island Department of Environmental Management’s Office of Technical and Customer Assistance - http://www.state.ri.us/dem/programs/bpoladm/manserv/hfb/boating/clnboat.pdf.
• Low Pollution Marine Engines: A Cleaner Way to Have Fun (PDF, 562 KB) - by the New Hampshire Department of Environmental Services.

Manufacturers of Environmentally Friendly Boat Engines

• Evinrude - http://www.evinrude.com/en-US/.
• Honda - http://www.honda-marine.com/index.htm.
• Mercury - http://www.mercurymarine.com/.
• Nissan - http://www.nissanmarine.com/.
• Tohatsu - http://www.tohatsu.com/.
• Suzuki - http://www.suzukimarine.com/.
• Yamaha - http://www.yamaha-motor.com/products/categories02.asp?lid=5&lc=otb.

Additional Information on Clean Boating

• List of Massachusetts Pumpout Facilities - http://www.mass.gov/czm/nda/pumpouts/.
• Massachusetts No Discharge Areas - http://www.mass.gov/czm/nda/.
• National Clean Boating Campaign - http://www.cleanboating.org/default.html.