Shore water auto fill / shut-off and filtering system

[LoudMusic]

We're stuck at marinas for a while as we continue to work full time, so we won't be running the water maker to fill our tank in these gross murky waters. I've been topping up from the dock water every few days so far, which I'm not particularly concerned about as the previous owner had been doing this for years.

However, I'd like to add some pre-filtering if anyone thinks that's a good idea, and it'd be really nice if I didn't have to deal with filling the tank. Either cut over to using shore pressure or have auto cut off and leave the dock spigot open.

I don't even know what to search for on the internet. Can someone give me pointers in the right direction?

[ranger58sb]

We use household size filters in line when we fill our tanks. The first is a "Big Blue" sump with a dual-gradient (25 micron/1 micron) filter element, DGD-2501. The second is a smaller GE Smartwater sump with a .5 micron carbon block filter element (I forget the designator for that one). All from filtersfast.com.

There are several threads around here on water filtration; see posts by Thinwater.

If I connect to the dockwater inlet, I have to remove the second filter, since it cuts flow too much. We rarely do it, but being connected for any length of time to the shorewater supply suggests it'd be useful (and safer) to install a limiter at the dock, either a timer or a quantity counter, etc.

-Chris

[Dockhead]

There are quite a few reports of boats sunk as a result of failures of auto fill shore water connections. I'm not sure I would take the risk just to save a bit of filling up. Probably not.



I guess it's a matter of perspective how much trouble that is. I spent years on a mooring with no water or power, and if I spent an extended time on board, I had to leave periodically to go get water. So being on a dock with water next to my slip is luxury, from my point of view!

[atoll]

check out caravan and rv suppliers for pressure reduction valves if you want to hook up to mains supply ,this will reduce water pressure from mains pressure~3bar to~1bar suitable for boat pipework,but you will still risk flooding if a pipe bursts

[a64pilot]

You don't want a continuous connection for the reasons stated, sinking the boat. Caravans don't sink.
Plus if you want real effective filtration, chlorine removal and fine sediments, then you have to have a low flow rate, one that is way to low to use direct connected.
Chlorine removal takes dwell time, the water has to flow through slowly for chlorine to be absorbed, so that means either a trash can sized filter, or very low flow rates.

The little blue ones you see people use are completely ineffective at anything other than rock removal

[Dockhead]

Originally Posted by atoll

. . . but you will still risk flooding if a pipe bursts

It's important not to underestimate the seriousness of this.


Normally a leak in the fresh water system cannot sink your boat, even if the bilge pumps are non-functional. The water is already on board and transferring it from tank to bilge has no effect on buoyancy.


Therefore, fresh water systems are not designed to standards necessary for other systems which affect watertight integrity. If you connect them to an unlimited supply of external water, all this is out the window. Suddenly parts of your systems not designed for a critical task like keeping the boat afloat, are called upon to do just that. Imagine you were connecting your entire fresh water system, to an open through-hull. It's roughly the same thing.



I think it's a fairly bad idea, actually.

[Bleemus]

Always turn off shore water on dock when leaving the boat.

[TrentePieds]

Let me add my voice to the warnings already given. Deliberately arranging your boat so that if there is a malfunction while you are absent, the boat will be damaged or even sink is far from a good idea.

Even if you or someone else shuts off the water before the boat actually sinks, water rising above the soles will damage the furniture to the extent that repairing it will probably not be economically viable.

Consider that filling a tank the old-fashioned way every three days or so, as I do mine, is a very small price to pay for not having to mow a lawn :-)!


TP

[jmh2002]

Isn't this part of the normal (pleasant) rhythm of life when living aboard?

Check the lines, check the batteries, check the water, etc, etc, adjust and top up as necessary?

I guess to solve this problem you could live ashore in one of those strange things called a house where all of this isn't necessary, but that kind of defeats the purpose doesn't it?

[TrentePieds]

MyBeloved, when she needs a break from "work" aboard sez "maybe I'll just top up the water" :-)

TP

[hellosailor]

"All from filtersfast.com. " Great folks. Competitive "white box" products and branded ones. Good pricing, fast shipping. fwiw.

I'd rather fill the tanks every day or two, so there's absolutely no chance to forgetting to turn off the pressure water, which just might overfill and sink the boat. It isn't *that* hard a task, considering the possible return.

If you have no indoor plumbing, you never have to call a plumber at holiday weekend rates in the middle of the night.(G)

[jmh2002]

Originally Posted by TrentePieds

MyBeloved, when she needs a break from "work" aboard sez "maybe I'll just top up the water" :-)

TP

Exactly. 'Let me just check the fenders and the bow lines she says' - 30mins later she is still there admiring the pleasant view (oops, I mean 'thoroughly checking those pesky bow lines!).

[LoudMusic]

This is why I ask these questions. Thanks to all for your thoughts!

Now if you will all follow me over to my next thread ...