Draining drinking water

[Trundletruc]

Every year we leave our boat in Greece, and before we leave I drain the water from the drinking water tanks using the sink taps. Up to now I have not worried about the remaining water freezing because the temperature in the winter does not usually go much below freezing. However, My boat (B36 2002) has a blue pipe that is connected to the lowest part of the water system that comes up by the side of the engine. This is obviously there to drain the whole system.
Has anyone got ideas of the best way of removing the water to the outside of the boat? Will a hosepipe syphon work or do you need a pump of some kind. A syphon obviously will not work if the boat is in the water as the lowest part of the drinking water system is below sea-level. It would be preferable to have a way of draining the system rather than running the domestic water pump for ages wearing it out?

[Salty]

The domestic water pumps just go on and on, ask anyone when they last changed the diaphragm in theirs. Alternatively you could connect a separate hand pump to drain out your fresh water system, but don't make it permanent because you will soon revert back to using your domestic water pump. An alternative would be to shut off and leave empty one of your domestic tanks as the time for your final departure approaches, and run your remaining tank down, only adding enough water for immediate use instead of completely filling it.

[MarkTheBike]

I made up a carrybox with a big motorbike battery and a 12v run-dry pump, with floppy neoprene hoses. I use it to bail the dinghy, empty dregs of water in the bilge, use it for hosing things down. Because it's a run-dry pump, I can leave it running (e.g. in the dinghy) for 15-20 mins whilst I put the kettle on and it'll just pump until it's dry. The pumps are really cheap, about £15 in the UK (got mine in Machine Mart, I think). They sound just the job for you. Connect up to your blue pipe and pump into a bucket. Doesn't need the fancy box, I built that just so I had a portable 12v socket. I'll take pics of it next time I'm down there if you're interested.

[Trundletruc]

Thanks MarkTheBike. I think the 12v pump is probably the best idea, I will have s look on the net for a suitable run/dry one.

Thanks

[DT]

I used my rib inflater pump stuffed with some electrical tape into the deck water filler inlet , wasn't perfect but it kept the pump primed to end of the pump out. 
Nessesity is the mother of all invention , some of those inventions are mother ........