Well, just to add my take on salt water at the galley. I have always fitted a salt water pump to each of my boats. I use the Whale double action foot pump which gives good pressure for rinsing dishes etc, and I am very happy using a nylon thru-hull fitting with a modern plastic ball valve, reinforced nylon hose, and double hose clips. I feel this is a very secure method of getting salt water to the galley and the chances of failure and eventual foundering of the vessel are I think minimal, (yes, I know similar things were said about the Titanic!). I would only use a good quality valve which in New Zealand means the black body, blue handle Hansen ball valves which are pressure rated to 15 Bar. And I have a soft wood conical plug attached to the ball valve in case something should ever go wrong. For added security the hose could probably be led above the waterline with an anti-siphon valve fitted. I have never had any problems with blockage from marine growth, but sometimes when I am swimming around the boat I will poke a small screw driver up the thru-hull to clear any possible obstructions. I am not a big fan of multiple thru-hulls so on 'Footprints' the only thru hulls which are under water are the salt water intake, and galley sink drain. The thru-hull for the vanity basin in the head is above the waterline. Of course when leaving the boat unattended for any length of time we close the thru-hull valves which seems a sensible precaution.

Anonymous wrote:

I plan to dry the boat out, or be anchored in very shallow water, where the keels will probably touch the bottom at low water, very frequently.  In that case the intake may not work, or may be bringing in muddy, disturbed water.  The 10 litre container ensures that I have clean water.  

Yes, that's a valid justification for the container, but the only one that I can see. It depends on the proportion of time spent afloat/dried out, but a bucketful taken as the tide leaves me does the job for me.

Arne, I was just about to come back and edit this, because I remembered the clinching reason why I had decided against the idea.  (I love the Norwegian saying, by the way!)  II plan to dry the boat out, or be anchored in very shallow water, where the keels will probably touch the bottom at low water, very frequently.  In that case the intake may not work, or may be bringing in muddy, disturbed water.  The 10 litre container ensures that I have clean water.  Yes, I agree it is not obviously rational, and I can truly see both sides of the argument.  I'd also add that I can see I'm being a bit paranoid, too.

I've thought about the long pipe, but it's more complexity than I want and the small galley pump would be struggling to pull water through such a long pipe.

The pump emptying the sink will be a lot higher up, so I think that will be less of an issue.  It would be easy to fit a seacock by the outlet, too, if I feel it necessary.  The one on Badger never siphoned back, however.  The pump mechanism does, in itself, provide a bit of a barrier against water ingress, being much heavier than that for a galley pump.

I'm wondering, Annie, why you aren't going for a seatube for the seawater? 10mm copper tube, wrapped in GRP to make it up to 13mm so that the usual hose size for a galley pump will go straight onto it. Totally safe and maintenance-free, and frees up the space that a 10L seawater container would occupy. The point of using seawater at all is that there's an unlimited supply of it out there - why restrict the supply to a 10L container that will need refilling quite often?

I did think about this, David, but the main reason is that I would feel it necessary to use a seacock in the pipe.  Should the boat be swamped or knocked down, the sink inlet could end up below the waterline and then seawater could come up the pump - under pressure I should imagine it could easily siphon back.  I'm also a little concerned about the issue of marine growth.  One of Fantail's cockpit drains got choked by an oyster and that was a copper tube. 

Noel B did this on one of his boats and found you need pure copper: his tube corroded;

It is, however, a tempting alternative.

I've just posted another update on my blog, for those of you who are following this project.