Making Water in Harbor?

[Chotu]

They say you shouldn't run your watermaker in the harbor because you can pick up oil and destroy the membrane.

What if you are picking up water from 3ft or a meter below the surface?

Could you then run it with confidence?

Or is it still a bad idea?

Could you run it in Biscayne Bay right near Miami? What's considered a "harbor" for this purpose anyway?

[Sailmonkey]

We run our watermaker 90+ percent of the time at anchor.

I give the water the smell and look test. If I’d swim in it I’ll make water with it.....but I’ll swim in some water that’ll clog pre filters rapidly.

[tkeithlu]

We run ours wherever we are, given that it produces reliably better water than various shore sources. So far, we have not had a problem, and yes, our seacock is well under water. Oil certainly can entrain. I have tried various settling and filtering arrangements for bilge water, and have not found a way to bring it down to the point that it does not leave a sheen if discharged. But then, taking water where there is no sheen would seem to cover that.

The other side of your concern is sewage. Nearly all city sewer systems combine storm drainage and household sewage, and when hit with gully washer rain dump both into the waterways. Biscayne Bay is a lot cleaner now than it was in the 1960s, and reverse osmosis is supposed to deal with such, but I still think I'd hesitate. I don't remember ever needing to run the water maker in a visibly dirty environment.

That's an equivocal answer to your question, which I think means that the topic deserves further discussion. Let's see what others say.

[Manateeman]

If the water is gin clear, you’d think you have no problem...right? You ought to see the detergent oil chemical mix used in the oil field called rig wash. It will dissolve any membrane. Who knows what in the brown of river water now.
Take some gin clear water. Test it on your meter. Bring it to a boil and take a look and a quick smell at what’s on top. You need a laboratory to tell you what is really dissolved but it’s a fun test for chemists who dare to do it. I’ve seen harbor water so bad birds are walking on it. Think about running it through your membranes and into your tanks ? The membranes you have to worry about are the ones in your body not the water maker.
Happy trails to you.
Mark, a cranberry juice drinking manatee

[Stewie12]

The cleaner the water the longer your filters will last.

[dlane1181]

The safest procedure is to not make water in a busy harbor or a marina because of the potential for sucking in petroleum products which will destroy your RO membrane.

However, what Stewie12 said is spot on from a technical perspective, and what the others said about using a common sense approach are, too. The dirtier the water in which you run through your watermaking system, the faster you'll foul/clog your prefilters. That's not a problem as long as you are aware of their condition, and you clean (if possible) or replace your pre-filters in a timely manner. They protect the membrane from most contaminants and pollutants.

[seandepagnier]

Originally Posted by tkeithlu

We run ours wherever we are, given that it produces reliably better water than various shore sources. So far, we have not had a problem, and yes, our seacock is well under water. Oil certainly can entrain. I have tried various settling and filtering arrangements for bilge water, and have not found a way to bring it down to the point that it does not leave a sheen if discharged. But then, taking water where there is no sheen would seem to cover that.

so you freely admit you discharge oil? This is prohibited, and I have never done it.


I have found a way to bring it to the point of not leaving a sheen. You don't have an engine in the boat. When are you going to pay up for the real cost of your engine?

[kas_1611]

What's wrong with good old fashioned tap water? Been filtered, treated, tested and certified. In many cases it is cleaner, better for you and way way way cheaper than bottled water.

[rslifkin]

Originally Posted by boat_alexandra

I have found a way to bring it to the point of not leaving a sheen. You don't have an engine in the boat. When are you going to pay up for the real cost of your engine?

That might top my list of pompous "holier than thou" forum responses... But either way, having an engine isn't the problem. If you're getting oil in the bilge, something is wrong. Any well designed engine installation should contain any leaked oil. I've got 2 engines and a generator, not a drop of oil in the bilge (and I keep some oil pads down there just in case. Any leaks from the generator are contained in a drip tray under it. Any leaks from the engines are contained in the (dry) bilge sections under them (complete with absorbing pads). The bilge sections under the engines have no limber holes specifically with the intent of containing any oil leaks.

[mikedefieslife]

Normally you can't anchor in harbours. I run mine at anchor. As others have said, so long as there isn't obvious oil around, you don't have too much to worry about. Let the filters do their job

[barnakiel]

I know there is a group of proponents of drinking one's own piss as a cure, but I would be very cautious, just in case the watermaker fails to remove this or that from harbour water.


Maybe in a small Scandinavian harbour, off season, you are OK.


But very many big cities have sewage outlets run into their basins and marinas. There will be bacteria, virus, metals, chemicals, etc. You name it. Probably wash off from boatyards and big ships too.


If the harbour sits on a river, it can be even more risky - think of all the farms, factories and human dwellings upstream.



Personally, in such a harbour I would not touch it. Too much risk to my health, imho, and too hard on the equipment.


barnakiel

[Chotu]

Originally Posted by kas_1611

What's wrong with good old fashioned tap water? Been filtered, treated, tested and certified. In many cases it is cleaner, better for you and way way way cheaper than bottled water.

Absolutely nothing. Filtered tap water is the best solution of all.

It has a couple drawbacks.

1) it's not where I'm anchoring
2) it's very heavy

For these reasons, the sun will be producing the water on my boat.

[Chotu]

Originally Posted by mikedefieslife

Normally you can't anchor in harbours. I run mine at anchor. As others have said, so long as there isn't obvious oil around, you don't have too much to worry about. Let the filters do their job

Ah... Ok. I think I'm not clear on the definition of a harbor actually. Lol

So for this advice people give about not running it on a harbor, it means don't run it at a dock or in a mooring field or in a stagnant body of water basically?

There are lots of harbours that have really fresh water in them due to tidal flow in/out. Point Judith Harbor of Refuge comes to mind. The small harbor on Block Island. Provincetown harbor. Camden Harbor.

[sailorboy1]

A watermaker is basically going to remove anything bad in the water (including sewage) and could be run anywhere (I would run it in Biscayne Bay without issue). But it may go through a lot of filters. I have seen what comes out of the air conditioning line strainer where I am now and doubt if a wm filter would last long. But of course if you need water you need water and you can rinse off the filters.

[sailorbobdeb]

Originally Posted by boat_alexandra

so you freely admit you discharge oil? This is prohibited, and I have never done it.


I have found a way to bring it to the point of not leaving a sheen. You don't have an engine in the boat. When are you going to pay up for the real cost of your engine?

Wow, just wow!!! No wonder lots of people hesitate to post . . .