BONE DRY BILGES – WHY BOTHER . . . ?
Some of life’s realities simply have to be accepted. Grandpa’s boat had it, Dad’s boat had it, too: just a little bit of harmless looking bilge water in the deep, and most often impossible to reach compartments down below. They call it a “vessel”, because it holds some water and we’ve been told to get over it.
But what if that residual, pesky bilge water was actually not at all harmless? For today’s bilges, a New Normal comes to the rescue, to be evidenced below.
Unlike a car or truck that’s open at the bottom, a boat’s hull needs to be well sealed. This keeps water from leaking in, but it also retains water that finds its way in from hatches, access panels and doors. Water often escapes from old fittings, it dribbles from deteriorated hoses, it trickles from packing glands, oozes from prop and rudder shafts and drizzles into the bilge courtesy of your boat’s A/C condensation. Worse yet, and relentless: Humidity entering the boat’s compartments, once cooled by that aforementioned air conditioner (or by cooler outside temperatures), usually ends up as condensed water in the bilge as well. Sigh.
Once the bilge water rises high enough, the bilge pump will (unless it’s fouled up) come on, keeping the bulk of the water out, however, it can never grab that last bit of H2O and therein lays the problem.
Bilge pumps are generally well designed for high water flow. Their main function is to maintain vessel trim, and to buy additional floatation time, should the boat be in danger of sinking. Not something you’d want to venture out to sea without. Bilge pumps are a very important piece of safety equipment.
But what about the normal day aboard your boat. There is most likely some vile, stagnant water in the bilge, as evidenced by that mature vessel odor that permeates everything, even wiping out any ‘new-boat-smell’ in no time. There is probably some plant- or bacterial life growing in that standing bilge water under your salon. Yuck! The real problem, on top of that, is the condensation cycle: During daytime hours, sun radiates heat through the decks and hull of your boat, resulting in a rise of temperature inside the vessel’s poorly vented bilge areas. The warmer air accelerates the evaporation of stagnant bilge water, and it will also absorb more evaporated water than cooler air can. Later in the day, after the sun has set, the air aboard starts to cool. Dew point is reached when saturated air can no longer hold all that evaporated, previously absorbed water. Once dew point is passed, little droplets start to condense everywhere: on your motors and pumps, a fine mist is caking electrical wiring, panels and bulkheads, nothing is immune. Those tiny drops of condensed water, combined with that festering, botanical growth down below, promote mildew build-up in all locations aboard: above in the stateroom, in the salon on the second deck, in the galley as well as down yonder on those hard-to-reach surfaces. Furthermore, that condensation not only causes paint to flake, engines to rust, fuel/water tanks to corrode and electrical connections to fail. Unfortunately, that wicked moisture even finds its way into the gimbal bearings of the ARG or Seakeeper gyro stabilizer systems, and into the electric bow/stern thruster motors.
Everything that is exposed to that daily vicious condensation cycle becomes less reliable, as it ages more rapidly. Warranty repairs, followed by repairs out-of-warranty start to haunt the boat owner.