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Course Outline

“No Discharge Zones” are areas of water that require greater environmental protection and where even the discharge of treated sewage could be harmful.

  • Whenever a vessel equipped with a Type I or Type II MSD (these types discharge treated sewage) is operating on water that has been declared a “No Discharge Zone,”  the MSD may not be used and must be secured to prevent discharge. Closing and padlocking the Y valve by using a non-releasable wire-tie or removing the Y valve handle is sufficient. Locking the door to the toilet with a padlock or a door handle key lock is another acceptable method of securing the MSD while in a “No Discharge Zone.”
  • Generally, all freshwater lakes (and similar freshwater impoundments or reservoirs that have no navigable connections with other bodies of water) and rivers not capable of interstate vessel traffic are considered “No Discharge Zones.”
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