"We have a similar situation at Catalina. The most frequented coves are Avalon and Isthmus Cove. Avalon has a no discharge policy, the harbor patrol places fluorescent dye in your toilet upon your arrival AND they have a pumpout dock for those in need. Isthmus Cove has no such pumpout facility and accordingly, no dye program either."
Actually, the Isthmus has a new pump out at the fuel dock and there is a pump out boat in Cat Harbor, although you need to reserve it about a day in advance (or so I was told two years ago). What would be better is an independent mobile pump out service like Avalon, but there is no where near the steady volume to make it work.
I think SoCal marinas would be cleaner with Lecta San's authorized. The general compliance is pretty good, but there are larger live aboard boats that don't have a pump out service and rarely go to the pump out. I think a choice of either a pump out service or a Lectra San - type sanitation devise for live-aboards would go a long way to reducing what little non-compliance exists.
I think a lot of reaction to the sanitation devises is the 'ick' factor, not real knowledge. I wish they were allowed. I would be better all around.