Water & Poop

I guess someone might want to know how we take on water and dispose of used water (toilet waste), so here is an entry about that.

We could pull into a marine and pay about 50 cents per gallon (in Bahamas) to fill up our two fresh water tanks but we don’t have to because we have a water maker installed on the boat. You might think that we are saving about $75.00 dollars to fill up our two 75 gallon tanks, but in reality a water maker can cost over five thousand dollars installed on this boat. We are gold platters (spoiled).

When making water, the seawater enters the boat via a thru hull fitting below the waterline. It goes through a small strainer with a metal mesh screen.

After that it goes through a another bigger filter before entering the two priming pumps. These two pumps push the seawater at about 60 psi into a bigger pump. The bigger pump is a piston type pump that increases the seawater pressure up to 600 psi. Yes, that is a lot of pressure.

The high pressure seawater is then forced through a special 36 inch membrane that filters out all the salt and lets through only fresh water. This filter membrane operates on a 10:1 ratio, that means that for every 10 gallons of seawater introduced it produces 1 gallon of fresh water.

The fresh water is diverted into one of our two holding tanks (which ever one is selected). The remaining seawater is pumped over board through a different thru hull fitting.

 

Each one of the 75 gallon fresh water tanks are built into the bottom of each of the hulls on our catamaran.

In the picture below you can see the water pouring into the built in tank from the water maker.

The water maker makes about 12 gallons of fresh water per hour and it takes about 6-7 hours to fill up an empty tank. The maker uses our 12 volt batteries as power and after the six hours I will have to recharge  the 6 “house batteries” with the diesel generator. I have found that I need to treat the fresh water with bleach so things don’t start growing in the water tanks. I add 1 tablespoon of bleach per 30 gallons.

The tank that holds the toilet waste must not be dumped close to shore. You have to be three miles off shore to empty your tanks or you can have them pumped out at a marina. Here in the Bahamas there aren’t any pump out stations on many of the islands so the waste makes it way back into the ocean.

Here aboard this boat we are water pigs. We have a hot water tank that is heated every day from the generator which at the same time charges our batteries and allows use to use the electric skillet to cook breakfast. So after breakfast we take showers. I’ve got it down to about 3-4 gallons per shower. Not Bad. Turn water on to wet down, shut off, soap up, turn water on to rinse off. I’m glad that I’m not on one of these boats out here that have to ration their water, I hope this water maker keeps pumping out the goods!