The Future Of 2-Stroke Boat Engines: Banned Or Not?

Two-stroke boat engines are not banned for use on all waterways in California, and there are no plans to implement a ban. However, they are considered high-emission engines, and some lakes and cities prohibit their use. The United States Environmental Protection Agency's gasoline marine final rule, published in 1996, established hydrocarbon emission standards for 2006 gasoline marine engines, but this only applies to new engines, not those manufactured before 2006.

Two-stroke engines are not banned in California

The California Air Resources Board (ARB) has developed standards for new outboard and personal watercraft engines based on actual emission levels, regardless of engine type. These standards aim for cleaner-burning engines without specifically banning two-stroke engines. The ARB regulations affect the manufacture and sale of new marine gasoline two-stroke engines, requiring vessel engine manufacturers to build cleaner emission engines.

Direct injection two-stroke engines, manufactured since 1999, are considered clean emission engines and can be used on every water body in California, except for some waterways with generic prohibitions, such as banning all motorboats or personal watercraft. These engines typically have a label sticker indicating their compliance with California Air Resources Board emission regulations.

While there is no ban on the use of high-emission two-stroke vessel engines in California, the state has taken steps towards reducing pollution from small gas-powered engines. For example, in 2024, California will ban the sale of new small off-road engines (SORE) used in equipment like generators and lawn equipment. This ban is part of California's strategy to reduce pollution, as small off-road engines contribute significantly to ozone formation.

Direct injection two-stroke engines are considered clean emission engines

The direct injection two-stroke engine has a lower emission rate compared to carbureted and electronic-injection two-stroke engines, which are considered high-emission engines. The latter type of engines were generally manufactured prior to 1999.

The direct injection two-stroke engine has a lower emission rate because it has better fuel economy, lower oil consumption, and improved idle performance.

Two-stroke engines are high emitters of unburnt fuel

The high emissions from two-stroke engines pose a serious threat to the marine environment and human health. In the US, two-stroke engines are the primary source of toxic pollution in waterways, with 75% of all boats and personal watercraft powered by them. They release a significant amount of oil and fuel into the water, with estimates suggesting that every year, marine two-stroke motors spill 15 times more oil and fuel into waterways than the Exxon Valdez disaster.

The emissions from two-stroke engines contain a range of toxins, including hydrocarbons, polycyclic aromatic hydrocarbons (PAHs), benzene, and toluene. These toxins are harmful to both marine life and humans. Research has shown that even low levels of hydrocarbon pollution can cause chromosomal damage, reduced growth, and high mortality rates in fish. PAHs, in particular, are highly toxic and can cause acute photo-toxicity in aquatic organisms within minutes or hours of exposure. They are also carcinogenic to mammals and are regulated as toxic contaminants by the N.Y. State Department of Environmental Conservation.

The impact of two-stroke engines on the environment has led to some restrictions on their use. While they are not banned in California, certain lakes prohibit their use due to concerns about water quality. Additionally, new emissions standards are being implemented in some places, such as Canada and Queensland, Australia, which will require two-stroke engines to comply with reduced emission levels.

There are no saltwater or river restrictions in California on two-stroke engines

Two-stroke engines are not banned for use on all waterways in California. There are no saltwater or river restrictions in California on two-stroke engines. However, there are some local restrictions on personal watercraft (PWC) such as jet skis. These bans are not based solely on high-emission vessel engines.

A number of cities, counties, or districts have followed state law, allowing local public agencies to regulate boating in certain categories. State law allows local public agencies to regulate boating in three categories: Speed Zone, Special-use Areas, and Sanitation and Pollution Control. A special-use area is a portion of a waterway set aside for specific activities, excluding other incompatible uses or activities.

Some examples of local restrictions on PWCs or two-stroke engines include:

• San Francisco has prohibited personal watercraft within 1,200 feet of its shoreline.
• Berkeley Marina does not allow PWCs within 1,500 feet of the shoreline or fishing pier, except in a designated 200-foot-wide access corridor.
• Canyon Lake, County of Riverside, does not allow PWCs.
• The City of Carlsbad restricts PWCs on part of Agua Hedionda Lagoon.
• The City of Los Angeles does not allow PWCs in Pier 300 shallow water habitat.
• The City of Sausalito does not allow PWC launching or retrieving.

It is important to always check with the local waterway manager about updated restrictions, as these may change over time.

Two-stroke engines are banned on some lakes

Two-stroke engines are not banned on all waterways in California, nor is there any plan to do so. However, some lakes have prohibited the use of these engines due to their high emissions.

High-emission carbureted and electronic-injection two-stroke engines, generally manufactured before 1999, are not banned on all waterways in California. While there are no salt-water or river restrictions in California on high-emission two-stroke engines, some areas, such as San Francisco, have banned personal watercraft within a certain distance of the shoreline.

High-emission two-stroke engines are prohibited on some lakes, such as Lake Tahoe, due to concerns about water quality and pollution. These engines can emit up to 25-30% of their fuel unburned into the water or atmosphere, which can contaminate drinking water sources and harm the environment.

Direct injection two-stroke engines, manufactured since 1999, are considered clean emission engines and can be used on every water body in California, except for some waterways with generic prohibitions, such as banning all motorboats or personal watercraft. These newer engines have direct fuel injection capabilities that result in lower emissions, making them compliant with emission standards.

It is important to note that the regulations set by the California Air Resources Board (ARB) and the United States Environmental Protection Agency (EPA) are directed at the manufacture and sale of new marine gasoline two-stroke engines, and not at the use of existing engines. Boat owners are not required to modify their current engines or face penalties. However, the new generation of outboard and personal watercraft marine engines offers significant environmental and performance advantages, including improved fuel economy and reduced smoke, fumes, and noise.

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