I have two holding tanks, Grey and Black. The Grey water tank's piping died and I 'm wondering if I really need a grey water tank at all.   I know some places like Lake Champlain require a black water tank but is any one aware of an  area on East Coast, Caribbean ect that requires a Grey Water holding tank?  I'm tempted to cap it and be done with it. Only other problem is that the sinks/shower drain into the Grey Water tank which is down at the top of the  keel (steel boat, tank is integral to hull)  The tank is then pumped overboard or to the deck via a macerator type pump.  The tanks and the pump out thru hull  and three way direction valve are all below the water line.  I assume that the macerator's duck bill valves act as a check valve and prevent any seawater back flow from the ocean itself.  There is NO vented loop.  It's been this way for the 20 years I've owned her with never a problem.  Assistance, Ideas Comments Please.  Russ  

Russ, my thoughts tend toward- 'what if the pump, or any part of it fails and cannot keep water from back-flowing?' I'm not certain that I'd make decisions based on 20 year history, but instead on 'what if'? Most, if not all ABYC recommendations first developed because of failures. Twenty years ago many things were done differently because they didn't have the awareness that we now have. I've seen all kinds of problems with failed plumbing, so my mind set is to not trust it to not fail, and install systems with this in mind. *Rudy & Jill Sechez tems* *BRINEY BUG-a 34' Sail-Assisted Trawler * *Anchoring Consultants-trawlertrainingabc.com* *850-832-7748 * *Georgetown SC Northbound-Chesapeake* > >