Gasoline constituents, in the form of volatile organic compounds (VOCs), include BTEX (benzene, toluene, ethylbenzene and xylene). Studies conducted on lakes such as Lake Tahoe in California and Whitefish Lake in Montana indicate that BTEX and other compounds found in water bodies are directly related to motorized watercraft activity.
BTEX are known to cause a myriad of human health concerns, including cancer, birth defects and damage to the nervous system, liver, and kidneys. BTEX exposure can result from inhalation, ingestion and/or contact absorption through the skin. BTEX also has an adverse effect on aquatic plants and animals.
Practice Responsible Boating
- Drive at safe, fuel-efficient speeds.
- Watch your wake and slow down if it gets too big. Large wakes erode the shoreline and damage wildlife habitat.
- Observe no wake speeds within 200 feet of all shorelines.
- Stay away from shallow areas. Motors churn up bottom areas and re-suspend nutrient rich sediments.
- Keep a trash bag handy to collect and store all trash, including cut fishing line.
- NEVER dispose of sewage overboard – it is ILLEGAL. Keep all sewage sealed in a holding tank for appropriate disposal at a marina.
- Plan ahead; sewage-dumping stations near lakes are extremely limited.
- Enjoy the natural quiet of the lake. Consider canoeing, rowing sailing or paddleboarding. Avoid playing loud music because sound carries easily over water.
- Stay away from birds and their nests, as well as other animals. It is illegal to harass wildlife and your actions may separate the young from their parents or chase them out of their natural habitat.
- Operate watercraft safely and courteously. Avoid congested areas when possible.
- Obtain a copy of and abide by Montana’s boating laws.
2-Stroke vs. 4-Stroke
A 1996 EPA report found that 4-stroke engines are 75- 95% cleaner than carbureted two-stroke engines. Scientific reports indicate that engine inefficiencies in carbureted 2-stroke engines can affect water quality: 30% of 2-stroke watercraft fuel is released unburned directly into the water via the exhaust system.
The California Air Resources Board found that a typical personal watercraft (carbureted 2-stroke) that consumed five gallons of gasoline per hour and operated 41 hours per year discharged between 50 and 60 gallons of unburned fuel into the environment.
The watercraft industry is responding by improving technology. However, if you’re in the market to purchase a personal watercraft or outboard motor, make sure the model you are looking at is not the carbureted 2-stroke type. For all outboard motors, make sure your engine is tuned so that it operates at maximum efficiency. Take care not to spill oil or gas while refueling.
Benefits of 4-stroke:
- Quiet and smooth;
- More fuel efficient;
- Less polluting;
- More reliable;
- Gasoline ready – no mixing oil and gas;
- Smooth idling;
- Great trolling motors;
- Accepted at any body of water that allows motorized boats, some areas have banned 2-stroke boat engines;
- Readily available, almost all new production is 4-stroke.
Return to Chapter 4 Table of Contents