1. Prevent oily discharge from the bilge.
2. Spill-proof your oil changes
3. Spill-proof your fueling practices
4. Do not add soap
5. Minimize boat cleaning and maintenance in the water.
6. Reduce toxic discharges from bottom paints
7. Dispose of hazardous waste properly
8. Plan A-head! Manage sewage wastes properly
9. Stow it, do not throw it!
10. Reduce gray-water discharges
According to Coastal.ca.gov