Filtering rainwater

geem

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We have an off grid holiday home and have always used rain water for washing, washing up etc, but until last year we loaded the car with containers of drinking water from home. After a week of the family visiting we were running very short of drinking water. I did a bit of research and found British Berkefeld Filters They sounded good, so bought an 8.5L version. We have now spent two extended summers drinking filtered rain water. It tastes better than chlorinated water with no ill effects. Our rainwater is stored underground, so keeps fairly cool, but often comes out of the tap with a brownish tint. We have to wash the slime off the outside of the filters every couple of weeks to keep them flowing. We keep the header tank topped up and have a constant supply of fresh drinking water. Just storing a small quantity of filtered water means it doesn’t go off. It’s obviously not suitable to carry a stainless water filter on a boat, boat it wouldn’t be too difficult to adapt the idea with a header tank with the candle filters dripping into a storage tank.
That sounds horrible🤔
 

noelex

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Rainwater collection is a valuable solution/adjunct on a cruising boat. It is surprising that more cruising boats do not offer this as an option.

I think part of the difference is cultural. It is not unusual to use rainwater exclusively for Australian rural properties. Sickness is very rare. This water is collected from roofs that are harder to keep clean than anything on a boat.

If nothing else, rainwater tastes much better than "city" water, especially marina water where often it has passed through a long array (of usually plastic) piping.
 

mikefleetwood

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Rainwater collection is a valuable solution/adjunct on a cruising boat. It is surprising that more cruising boats do not offer this as an option.

I think part of the difference is cultural. It is not unusual to use rainwater exclusively for Australian rural properties. Sickness is very rare. This water is collected from roofs that are harder to keep clean than anything on a boat.

If nothing else, rainwater tastes much better than "city" water, especially marina water where often it has passed through a long array (of usually plastic) piping.
A friend of mine lives on a hilltop in the middle of nowhere, a couple of hours from Melbourne. Next to the house is a huge concrete tank, fed from the runoff from the roof - that provides all their water, including drinking. Tastes OK to me, but considering it receives no treatment I was a little concerned when we stayed with him. Mind you, he's survived living there for nearly 30 years without ill-effects, so it must be OK!
 

geem

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A friend of mine lives on a hilltop in the middle of nowhere, a couple of hours from Melbourne. Next to the house is a huge concrete tank, fed from the runoff from the roof - that provides all their water, including drinking. Tastes OK to me, but considering it receives no treatment I was a little concerned when we stayed with him. Mind you, he's survived living there for nearly 30 years without ill-effects, so it must be OK!
Often those that live off collected rainwater tanks with no treatment build up an immunity to the bugs. It only becomes a problem occasionally when those without immunity drink the water.
We lived off a slightly dodgy spring water supply for 15 years in the Peak Park in Staffordshire. We would occasionally find frogs and bugs in the prefilter
 

Neeves

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Often those that live off collected rainwater tanks with no treatment build up an immunity to the bugs. It only becomes a problem occasionally when those without immunity drink the water.
We lived off a slightly dodgy spring water supply for 15 years in the Peak Park in Staffordshire. We would occasionally find frogs and bugs in the prefilter
In the village we lived in in Scotland the town lived off water collected from the burn running through the village. The collection point was up in a glen above the village. Dead sheep would often be found even further upstream in the burn. The filtration bed was a large, about the area of half a tennis court but only 200mm of sand, a simple sand filter bed.

The filter bed was cleaned by simply turning the bed 'upside down'. Just shovel the sand so that the top surface was at the bottom. The filter was then flooded and water pumped through the bed and the water used for 'washing' discarded down stream.

Population 2,000, there was never an issue with water and illness.

I suspect conditions have changed over the last and recent decades.

Jonathan
 

Snowgoose-1

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When I had cats and dogs they would turn up their noses at my nice tap water in bowls and could be seen drinking out of the pond and the dirty old wheel barrow. Perhaps it was the bleach.

I filled up from a spring one time at Harty Ferry in the Swale in Kent . It tasted great but "went off" after a few days. Probably wasteful , but I use the cheap Tesco bottled water for drinking on the boat.
 

Neeves

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If you use Admiralty Pilots, or at least old versions, they included for 'out of the way' places the location of local streams and rivers useful to top up your water (barrels). Australian Pilot books were based on surveys conducted in boats not much different in size to our yachts - and they had the same problems.

Jonathan
 

noelex

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Personally, one of the things I hate about returning to "civilisation” is the poor tasting tap water.
 

NormanS

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We used to regularly fill our water containers from the "Mad Burn". Never did me any harm. Ha Ha He He. 🥴🥶
For those who don't know, the Mad Burn is a torrent of water coming down from the well watered Cuillins of Skye, into Loch na Cuilce, in Loch Scavaig. The run-off from the mainly bare rock, has to be seen and heard in heavy rain.
 

Kelpie

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We used to regularly fill our water containers from the "Mad Burn". Never did me any harm. Ha Ha He He. 🥴🥶
For those who don't know, the Mad Burn is a torrent of water coming down from the well watered Cuillins of Skye, into Loch na Cuilce, in Loch Scavaig. The run-off from the mainly bare rock, has to be seen and heard in heavy rain.
I used to be the skipper on the Bella Jane, I know that area pretty well 😁
 

noelex

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We used to regularly fill our water containers from the "Mad Burn". Never did me any harm. Ha Ha He He. 🥴🥶
For those who don't know, the Mad Burn is a torrent of water coming down from the well watered Cuillins of Skye, into Loch na Cuilce, in Loch Scavaig. The run-off from the mainly bare rock, has to be seen and heard in heavy rain.
There is no need for the "Mad Burn". There is torrent of water coming off a sailboat deck when anchored in this area and subject to heavy rain :).
 

Kelpie

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Resurrecting this topic...

Any ideas for how to physically pipe the rainwater into the tanks?
I want something that can easily be disconnected, so that if the panels are dirty I can let the first bit of rain run off.

The only thing I can really think of is to use a standard garden hose push fit connector, mounted on the outside of the coaming.

The other option would be the deck filler itself, but that's not much good because all the crap from the deck will end up in the tank too.
 

Neeves

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Resurrecting this topic...

Any ideas for how to physically pipe the rainwater into the tanks?
I want something that can easily be disconnected, so that if the panels are dirty I can let the first bit of rain run off.

The only thing I can really think of is to use a standard garden hose push fit connector, mounted on the outside of the coaming.

The other option would be the deck filler itself, but that's not much good because all the crap from the deck will end up in the tank too.

If you are living on board surely part of the regime is checking the weather forecast.

If its going to rain simply run round and wash the areas from which you will collect the water, solar panels, deck.... whatever. Wash it down thoroughly with clean sea water. Wait for the rain and rush round again with your broom and wash the deck of salt water - then collect the fresh water. If it rains frequently you may not need to spend too much time with a salt water wash.

A clean, new, sail (storm jib, trysail) makes an excellent rain water collector - if you plan ahead.

Depending on how desperate you are - the water will be good enough for showers, washing up (but you can do much of that with salt water) and some laundry. If the rain is prolonged the water will become increasingly fresher. Like desalinated water rain water contains no or few minerals and lacks the taste of 'fresh water' (whatever that is).

Nothing wrong with Scots rainwater nor that from a burn. For those who are connoisseurs of bottled water Blackford water comes straight, from Perthshire rain, well almost straight, of the Ochils and is perfect for a dash added to a decent malt whisky - but a bit expensive for doing the washing up.

Jonathan
 

Neeves

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Personally, one of the things I hate about returning to "civilisation” is the poor tasting tap water.

Many aspire, few are able

I think at least one or two people would suggest you are enjoying, a good, part of 'Western' civilisation and you rely on 'Western' civilisation to do so.

All credit to you.

Jonathan
 

Roberto

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Resurrecting this topic...

Any ideas for how to physically pipe the rainwater into the tanks?
I want something that can easily be disconnected, so that if the panels are dirty I can let the first bit of rain run off.

The only thing I can really think of is to use a standard garden hose push fit connector, mounted on the outside of the coaming.

The other option would be the deck filler itself, but that's not much good because all the crap from the deck will end up in the tank too.
Have a look at this

Clic & Fill - Navy Clic EN
I don't have one and think yours might be one of the very few occasions it could be useful.

Fwiw we collected water in buckets and jerricans, then transferred it into one of the main tanks through a simple gauze filter. Always used only the same tank (of three).
 

Refueler

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Been drinking rainwater for years without any problems, radar picks up the squalls so some notice the get the shampoo out and a bucket under the gooseneck with a reef in to guide the rain off the main. Off the awning as well. Always thought it would be cleaner than tap water most places.
But then I'd drink anything until recently 😊

Rainwater comes in many forms depending on the air quality its falling through.

I would never want to use RW that fell in a city for anything other than washdowns ... but if out in clear country / offshore - then I would drink it as well ... don't forget that its a credited way to gather drinking water in lifeboats etc.

Clean RW is of course very weak carbonic acid ... its why it erodes the Downs in Southern England etc. But its so weak that for us it has no effect. RW drops as they form - usually on a tiny dust particle - but as they fall - they absorb CO2 creating the carbonic acid... of about 5.6 - 5.7 pH. The dust particle is what some here collect in their filters, along with any other particulate picked up on its fall.

I have a box of Military Sterilisation tablets - 1 tab per 20ltrs ... basically a generic form of Miltons. Every so often - I dissolve a couple in a bottle and then dose my tanks on board ... leave for an hour or so and then pump a few litres through system. eBay has loads of these ex military tabs ..
 
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geem

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Resurrecting this topic...

Any ideas for how to physically pipe the rainwater into the tanks?
I want something that can easily be disconnected, so that if the panels are dirty I can let the first bit of rain run off.

The only thing I can really think of is to use a standard garden hose push fit connector, mounted on the outside of the coaming.

The other option would be the deck filler itself, but that's not much good because all the crap from the deck will end up in the tank too.
We collect off the suncover. We use 1" plastic cheap through hulls in the canvas cover. From here we pipe with 1" clear plastic pipe. We collect off both sides of the sun cover so we T the two sections of pipe together. From here, the single 1" pipe goes into the deck filler via a 10" filter housing. We only insert the pipe into the deck filler when the rain has been running for a while to make sure everything is clean. Fortunately our deck filler is raised above the deck on the mast base so water from the deck doesn't run in
 

rogerthebodger

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Not collecting rainwater but I fitted a 3 way 4 port valve from the output of my watermaker

This allows me to divert water to either of my 2 water tanks and the 3 rd way goes to a forcit in the galley sink so I can discard the initial output while having access to the output to check water quality before adding to any tank
 

geem

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Not collecting rainwater but I fitted a 3 way 4 port valve from the output of my watermaker

This allows me to divert water to either of my 2 water tanks and the 3 rd way goes to a forcit in the galley sink so I can discard the initial output while having access to the output to check water quality before adding to any tank
In the tropics, the rainfall worth collecting can be torrential. I once collected 500 litres off our sun cover in 2 hours. You need large diameter pipes to collect this or it will just be wasted as it overflows. I think 1" is about right. That would be a big expensive diverter valve at 1". For collecting off a cover or bimini, it a very cheap option to just leave the pipe out of the deck filler until you are ready
 
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