Captain's Log

06/19/2007

Water, water everywhere,  but we have to make it fresh if we want to drink on the GOLDEN BEAR. 

Our tanks hold about 135 Tons (35000 gals.) of fresh water.  We use about 40 tons a day (10,000 gals).  That is about 40 gals per person per day, but much is used in the galley and in the laundry, so you don’t see it.  It is taking us 14 days to get from Guam to Honolulu, and we only have water on board for about 3.5 days.  Thus, we have to produce it.

In the engine room are evaporators that manufacture fresh water from sea (salt) water.  The engine department is in charge of these evaporators and their operation.  By reducing the pressure within the evaporators, they are able to get water to boil at a lower than normal temperature. This produces vapor, which is condensed into fresh water, and very salty water, which is washed over the side.

When the ship is traveling at 15 knots or above in speed, the main engines produce enough heat (“waste heat”) to operate the evaporators.  When we are traveling slowly, we use steam from the boiler to help heat the sea water in the evaporators. 

With both evaporators working at maximum capacity, we can produce 65 plus tons of water a day.  This is important, because we cannot make water in port due to high levels  of bacteria.  The evaporation process will not kill all of it.  Therefore, we always leave port low on water and need to catch up.  We can produce about 25 tons a day more than we use, so in 3 or 4 days our tanks are filled. 

 Captain John Keever