The 361 holding tank mounted above and behind the head on wall. It has a plastic cover for it to make it look nicer. The Y diverter was under the sink near the seacock. The tank fill went over the top, and the deck drain was also on top via a dip tube.
BTW, med MSD regs:
Spain
Spain has holding tank requirements which together with their pollution legislation, essentially mean that vessels cannot discharge untreated sewage within Spanish territorial waters (12 nautical miles). The Spanish legislation is ORDEN FOM/1144/2003, 28 April which for anyone who speaks Spanish can be found at
www.fomento.es and an unofficial translation of the legislation is also available.
Greece
In Greece the regulations relating to discharges and pollution make a holding tank a practical necessity although we are not aware of them being a legal requirement as yet. Caution should also be exerted with grey water in Greece.
Turkey
Discharge of any kind may be considered illegal. A black water tank has therefore been a practical necessity in Turkey for many years. New rules have been coming into force in some areas of Turkey (such as the Mugla District) over the last few years which require vessels to carry a Blue Card. If the rules are enforced to the full all black and grey water will need to be collected and pumped out ashore; the Blue Card will be used to monitor the amount of waste water deposited ashore to ensure holding tanks are pumped out rather than emptied into the sea.
France
French law requires that as of 1 January 2008 new vessels, whether French or foreign flagged, are fitted with a treatment system or retention tank for black water if they wish to have access to French ports, moorings and anchorages.
Users of older vessels which are not equipped with treatment systems or holding tanks for black water are, like all other pleasure yacht users, required to comply with the rules which prohibit discharge in ports and designated anchoring spots. They must therefore use shore toilets.
How these rules are to be applied or enforced is not very clear but it is anticipated that guidelines or a further law defining the extent and manner of application and any sanctions will be issued in the future.
In principal it is forbidden to flush toilets into canals and rivers, but as pump out facilities are few and far between until now discreet overboard discharging has been tolerated, this may of course change.