How many boaters do you think actually drink the water in their fresh water tanks? Start asking around the dock and most will admit that they bathe and wash, but stop short of filling a glass.
Yet obtaining good tasting, drinkable water from your boat's fresh water system is not all that difficult, if you understand the components, learn how to properly sanitize them and take the time to provide regular maintenance.
It seems that as our boats get bigger, so does our demand for fresh water. Years ago, water was delivered only in the shower, the head and the kitchen and bathroom sinks. Today, boats have multiple sinks, showers and heads, as well as ice makers, wash-downs, washing machines and even misters.
Those who have a high-quality water maker aboard and know how to properly use it have far fewer problems, because they are capable of generating pristine water. Those who don't are dependent on dockside water, which can complicate things because the quality is uncertain.
TODDMost fresh-water tanks are made of rotationally molded polyethylene like those shown here, though tanks of fiberglass and aluminum can also be found.
Water system problems generally manifest themselves in observable ways–the water is discolored, tastes poor or smells bad–but not all problems can be detected with your senses. Water that is contaminated with bacteria, cysts or chemicals may not show any visible signs.
The only positive way of determining water quality is by having the water tested. Local health departments or cooperative extension offices can give you a list of labs that will test your water, and home water testing kits are now available that, though not as accurate as laboratory tests, can at least send up a red flag when there may be a problem.
Just remember: testing is a snapshot indicating the quality of the water in your tanks and your system at that moment. Once you re-fill, the snapshot changes. Because water quality is constantly in flux, it is important to understand how your system works and how to properly maintain it.
TANKS AND LINES
The first step is to understand the infrastructure that conveys the water from the tanks that store it to the faucet that spits it out – all the tubing, pumps, filters, heaters, valves and other stuff that combines to provide water for bathing, washing, cooking and, yes, drinking.
Most of the fresh water tanks installed aboard boats today are made of rotationally molded polyethylene. In this process, polyethylene pellets are loaded into a hollow mold the shape of the tank. As the mold is heated and rotated, the pellets melt and cling to the inside walls of the mold. When enough time has passed to melt all the pellets and form a uniform wall, the mold is cooled and the tank removed. Most roto-molded tanks are on the order of 3/8-inch thick.
PLASTIMOBladder tanks, like those shown here, can fit in odd spaces.
After being removed from the mold, holes are cut for the tank fill, drain and vents. Threaded tank hoses are then heat-welded in place, providing the necessary connections to the rest of the water system.
Molded fiberglass tanks are also found – sometimes molded as part of the structure of the boat – using polyester or epoxy resin. Another tank option is a flexible bladder tanks. Whatever you have on your boat, it should be approved by the U.S. Food and Drug Administration for drinking water.
Moving out from the tanks, flexible water lines are the next component in the system. The most common are clear vinyl hose, which makes it easy to see when the lines get dirty. These should also be certified by the FDA for potable water and hot water lines should be denoted by red tracer threads in the vinyl hose.
There are some high-tech plumbing systems that utilize 15mm or 5/8-inch hose with special quick connect fittings. These make plumbing installation quick and easy by eliminating multiple hose clamps, but replacement parts can be difficult to find, so be sure to carry spares.
PUMPS AND HEATERS
Water is pulled from the tank and driven through the system by a water pump, which provides the water pressure that you feel at the tap. All but the most minimalist boaters use electric, multi-chambered water pumps, which provide a smooth flow of water. A built-in pressure switch turns the pump on and off as water is used. Maximum pump pressure is usually 45 PSI, with delivery rates ranging from 2.8 gallons per hour to 5 GPH or more.
JABSCOFresh water pumps provide the water pressure felt at the tap.
