Bestevaer 49ST

[noelex 77]

We installed a Spectra Ventura 150 on our old boat and it was excellent. It made all our water without missing a beat for almost 10 years. As we live on board essentially full time, that is a lot of water.

So we will be installing another Spectra watermaker. Given the much greater power generation of the new boat, I will probably fit the next size larger, the Cape Horn model.

KM have installed an aluminium tray with raised sides to catch any spills in the lazarette and also the standpipes for the feed and discharge, so installation should be relatively easy (famous last words ).

The watermaker feeds into a 60L stainless steel day water tank, which then overflows into the boat’s main water tanks. A separate tap in the kitchen allows this fresh water direct from the watermaker to used for drinking. The day water tank also provides the rinsing water for the watermaker. This is product water, so the rinsing water will contain no chlorine, even if the main tanks are filled from another source. As chlorine damages the membrane, this removes one potential failure point, although we will also maintain the chlorine filter.

As well, we have a deck rainwater collection system. This was also installed in our old boat and was very successfu. We largely stopped using this system when the watermaker was installed, but backups are important and the new system has a greater catchment area so we should be able to collect a great deal of water, if it works as planned.

[kmacdonald]

I really like the idea of the day water tank for drinking water. That eliminates any concern with rainwater collection. Did you choose a 12V watermaker because you don't have a generator or because you don't plan on making large quantities of water? With a rain water collection system the amount of RO water needed will be small-----drinking water only.

[noelex 77]

Once we installed the Spectra on our old boat we basically stopped collecting rainwater because it was not needed. The only exception was rarely over winter if there was a spell of particularly bad weather and we started to run low on power.

The Spectra provided all our water otherwise for showering, clothes washing etc.

The new boat has more solar and larger alternators so even without a generator power should not be an issue and rainwater will only be a backup if the watermaker fails (or before the watermaker is fitted).

More power and the bigger Cape Horn watermaker should allow enough water for some deck washing as well as machine (rather than hand) washing of clothes, but I don't anticipate much other change in our water usage.

[a64pilot]

Spectra, of course the larger ones, can make an enormous amount of water, they are not low volume watermakers.
Just they are not inexpensive either.
Those of us with AC “high volume” watermakers usually chose them cause we have a generator anyway, and seeing as how you have one, may as well use it.
I believe it’s whether you chose to have a generator is what likely trips the desire for a Spectra, there are other DC watermakers of course, but majority of them use so much power that they can’t realistically be run off of DC, without a generator to recharge the bank, then what is the point? The Spectra is so energy efficient that it can realistically make lots of water off of DC power from Solar, cause it uses so little.
That efficiency comes at a price of course, but that price may be less than an AC Watermaker and a generator.

[a64pilot]

Our little Haier washing machine uses very little power, I was surprised at how little.
However it uses an enormous amount of water, I measured it once but have forgotten how much, but it was something like ten or maybe more gallons per load.

[cj88]

When you're talking power efficient 12V watermakers then the CJD Watermakers DC60 watermaker is worth a look. 60lph @ 16A

https://www.cjdwatermakers.com/dc-watermakers

[john61ct]

DC or AC, just a matter of preference and how you're set up.

Mine is HO alt charging LFP, so a high gph DC watermaker fits well.

Rich at Cruise RO says he can substitute a DC motor on his units on request.

Advantages Spectra vs RO? Focus on high gph, lower cost reliability over time, easier repairs in primitive locations. Not energy efficiency.

I prefer to avoid AC in general, only thing plugging the boat into mains should do IMO is charge the bank more quietly and without fuel, like solar but faster.

[Pelagic]

[QUOTE=john61ct;2656072]

Rich at Cruise RO says he can substitute a DC motor on his units on request.
/QUOTE]

I asked Rich to do this for me and I am very happy with the versatility.

For me the main advantage of a high output DC RO, is that I have a variety of battery recharging sources, rather than just the Generator or a dedicated invertor, to run the DC pump

A common scenario for me would be to make water underway, outside of harbours where the seawater has less contamination. Often Motor sailing, my HO alternator keeps the offsets the DV loads nicely.

[noelex 77]

Rainwater collection:

We have not fitted (or even purchased) our watermaker yet, but as a back up to the watermaker we have installed a deck rainwater collection system.

We had this on our previous yacht and it could collect water in heavy rain. On the new boat the collection area is larger and there is less opportunity for water to escape. It has proven to be very effective. Significant water can be collected in even very light drizzle.


Fundamental to the system is the bulwark or high toe rail that is part of the Bestevaer design. The main purpose of this is to provide a secure grip. It is shame this feature has been lost on many cruising boat designs. It significantly adds to safety on deck, but as well as its primary purpose, it allows the deck to be used for collecting rainwater with only slight modifications during construction.

To collect the rainwater the deck drains are plugged and a small sandbag added. This allows the water to rise above the level of the tank fill.

The rainwater can be diverted into any of the three water tanks, but is normally fed into our “multipurpose” water tank. The “multipurpose” tank was conceived with a few potential uses in mind. Its primary purpose is to serve as an intermediate tank to store rainwater that can then be checked, filtered and if suitable pumped into one of the main water tanks. If the water is not suitable it can be used for washing or simply pumped out. The multipurpose tank can also be used as additional water storage capacity, supplementing the main tanks, or storage of shore water that may be OK but not ideal.

The tank has also been plumbed as a potential grey water tank. Discharge regulations are becoming much stricter and the mandatory use of a grey water tank is possible (likely ?) in the future.

Using the tank as a grey water tank obviously prevents its use as a conventional water tank at least without a very thorough clean (it is removable for steam cleaning). This is not the tank’s normal function, but all the plumbing is in place, (this is easy to incorporate at the build stage) so by opening a few valves the tank’s function can be changed. Rainwater can still be collected directly to the main tanks if this was the case.

We started cruising before even blackwater tanks were common. Many boats had difficulty conforming to the new and retrospective regulations. These days no new cruising boat would be sold without a blackwater tank, but history may be repeated with future legislation requiring grey water tanks so it is sensible to have this option incorporated into a new boat build. The “multipurpose” tank solves the problem of a grey water tank that would otherwise just take up space. A combined grey/blackwater tank is another option.

All of this effort is just a backup to our (future) watermaker. We found the watermaker on our previous boat reliable, but there is nothing sadder than a cruising boat and crew in port waiting for repairs/spares. This happens surprisingly often. So KISS where viable or at least have backups for anything vital. A watermaker, reasonable freshwater tank size with tanks where water of various quality can be isolated, and a super efficient rainwater collection system means we hopefully have all the possibilities covered.

This photo taken during construction shows the bulwark/toe rail:

[Kenomac]

Personally, I wouldn’t want to drink the rainwater coming off the deck on our boat. How in the world do you purify the water prior to use?

[a64pilot]

Originally Posted by Kenomac

Personally, I wouldn’t want to drink the rainwater coming off the deck on our boat. How in the world do you purify the water prior to use?

Through a sea gull filter is one way. If you look at its specs, it’s pretty impressive.
https://generalecology.com/info/techmemocert
We don’t want to either, and hope we don’t, but I have a catchment system just in case we have to. As I said my plan is to use the main sail but the deck fill is easy too, just block the drains as Nolex said and open the fill and make a dam.

However, next time you get into a good rain when sailing, look to see how much water comes off of the main, plus hopefully it’s cleaner than the deck.

[model 10]

We have a deck catchment set up and it might take a couple of days of rain to make the water taste ok. Once it tastes ok, it's amazing how much you get. Our bimini is the one that we use all the time. You can often fill a 6 gal jug in one down pour.

[noelex 77]

For Australians the concept of drinking collected rainwater is more acceptable. Even today, many of the houses in country areas collect all their water from the roof.

Houses have is the added complication of leaves and other organic matter accumulating in gutters and washing in the tank itself. Nevertheless, the water is not only drunk with few practical health problems, it is usually preferred over “town” water.

We take the precaution of giving the deck a wipe down and letting the rain water rinse for some time before diverting it into the tank. We very rarely tie up shore so there is less opportunity for pollutants to accumulate on the deck.

The rainwater is not always suitable for collection and there are also times when the deck is not clean enough, but the water is not collected if there are concerns. However, I am not sure Ken if the system would be practical on a boat with a teak deck such as you have on your Oyster.

On our new boat the rainwater water is stored in a seperate tank. If we want this water to enter our main tanks it is then is pumped through a large double filter. I am not sure these precautions are necessary, but it does help keep the main tanks clean. For the same reason we also filter any shore water that goes into our tanks.

Unfortunately, in many countries we have visited the water quality is poor. In most cases it is probably safe to drink, but when it is cloudy and smells it is not something you want, even in tea and coffee. A watermaker is great in these areas, but if you want to avoid the difficulties associated with bottled water, rainwater is the next best option.

In addition, we have a separate stainless steel day drinking water tank with its own tap in the galley. This tank is designed to be filled with fresh water directly from the watermaker before it overflows into the main water tanks. If the watermaker is not functioning (or not fitted) this tank also gives us the ability to have a different supply of drinking water. So rainwater could easily be kept out of our drinking water supply if there were health concerns. We can even keep the rainwater (or any other water source) just in the “multipurpose” tank for washing, or showering.

So our water system is very versatile, which is the key to managing water from marginal sources. However, rain water tastes better than municipal water and at least compared to the water from many countries I think is safer, so this is usually our premium water if watermaker water is not available.

[Wotname]

Originally Posted by noelex 77

For Australians the concept of drinking collected rainwater is more acceptable. Even today, many of the houses in country areas collect all their water from the roof.

Houses have is the added complication of leaves and other organic matter accumulating in gutters and washing in the tank itself. Nevertheless, the water is not only drunk with few practical health problems, it is usually preferred over “town” water.
If you can't eat vegemite, don't drink the tank water!
..........
So our water system is very versatile, which is the key to managing water from marginal sources. However, rain water tastes better than municipal water and at least compared to the water from many countries I think is safer, so this is usually our premium water if watermaker water is not available.

[john61ct]

I've spent many decades whole family and all the neighbors drinking only rainwater, including places with bounteous well supply.

Just basic common sense precautions are required.

Obviously depends on your current location too these days.