Where does poo and wee go in a cruiseship?

Ok, so when you go to the bathroom onboard a ship the waste usually goes to a holding tank and is usually emptied at each port. However before 2010 after 3 nautical miles away from shore the ship could dump treated waste and after 15 nautical miles away from shore you could dump untreated waste. This law was changed in 2010 and now they must hold it in a holding tank. I hope that helped :)