Please do not pump any oily bilge water over the side:
All bilgewater discharges must be in compliance with the regulations in 40 CFR Parts 110
(Discharge of Oil), 116
(Designation of Hazardous Substances), and 117
(Determination of Reportable Quantities for Hazardous Substances) and 33 CFR §151.10
(Control of Oil Discharges).
In addition: National Pollutant Discharge Elimination System (NPDES) 2.2.2 Bilgewater
- Vessel operators may not use dispersants, detergents, emulsifiers, chemicals or other substances to remove the appearance of a visible sheen in their bilgewater discharges.
Sure these regulations are mainly for larger vessels: over 65 ft / 400 gross tons, however the EPA is on the watch for "point source" violations. If it can be proven that the small boat operators are responsible, they will have the impetus to broaden the scope of the enforcement.
Vacuum up all the nasty stuff and flush it down a toilet (on land).
Many (most?) municipalities are quite specific on what chemicals can not be dumped into the sewer. Such as, one location specifies "non-toxic and phosphate free cleaners and detergents. Furthermore, cleaners and detergents should not be caustic or only minimally caustic and should be biodegradable."
Basically oils, grease, and chemicals are not conducive to the sewage treatment process.