Do not swim in a Marina!
June 27th, 2005 at a marina on Cave Run Lake near Morehead
Kentucky a woman drowned as a result of being electrocuted while
swimming off a houseboat. A second swimmer also received apparent
electrical burns. The houseboat air conditioner is believed to be the
source of the electrical current leaking through the water.
similar incident occurred at a dock in a marina on the Willamette
River's Multnoma Channel near Portland Oregon. Read the story about Lucas Ritz. Link
to newsletter that contains story.
have been other incidents like this where faulty wiring or equipment
have leaked current into the surrounding water through a submerged
metal part of the boat such as the boats I/O drive or thru-hull
fitting. This phenomenon only happens in fresh water marinas. There
have been no reports of this ever happening in salt water. Salt water
conducts electricity better than the human body. In fresh water the
opposite is true.
properly wired boat, per ABYC(American
Boat & Yacht Council) standards,
will have the green grounding wire connected to the battery negative
which is in common with the engine and other metal parts of the boat.
If there is an electrical fault there should be enough current to
ground to trip the breaker. Theoretically it is possible to leak
enough current out of the boat to cause injury to a swimmer without
tripping the breaker. GFIs (Ground Fault Interrupters) should be
installed on the boat on all circuits including battery chargers,
even though this is not currently required by the ABYC.
Ground Fault Interrupter (GFI) properly installed at the dock power
pedestal would prevent this from happening but is not required by
National Electrical Code. They have been installed and proven to work
despite some skepticism that there would be nuisance trips in a
marina environment. I think this would be the ultimate protection
because this would remove power if the shore power cord is
accidentally dropped into the water. If the shore power cable is in
excellent condition this would be a non event, but if the insulation
is even slightly damaged current could flow into the surrounding
water. Having a properly wired boat does nothing to protect against
faults between shore and the boat's main electrical panel.
Marinas can do
marina can install monitoring equipment such as Marina
Guard. This works
similar to a Ground Fault Interrupter except it provides a warning
instead of shutting off power to the offending device.
should I Do?
not swim in any fresh water marina because you do not have any
control over how shore power or other boats are wired.
forget to test your GFI after a power surge or a lightning storm.
If the electronics inside are fried, you are unprotected. Newer units are made to "fail safe" and will not work at all if damaged.