Many boats and some PWCs are equipped with two-stroke engines. Conventional two-stroke engines produce roughly 14 times as much ozone-forming pollution as four-stroke engines. Also, 25-30% of the fuel and oil of two-stroke engines is discharged unburned with a portion lingering in the water column for a period of time.
Federal law requires marine engines to meet tough emission standards. Many new, clean-burning engines are already available; and the new technology provides easier starting, faster acceleration, quicker throttle response, improved fuel economy, and reduced fumes and noise. See www.oregon.gov/osmb/clean/pages/cva.aspx for more information.
Even though vessel engines currently in use are not affected by the phase-in, the Marine Board encourages retiring old engines and replacing them with newer, more efficient models.