Bob Adriance, editor of Seaworthy, BoatU.S.'s insurance magazine, says the No. 1 cause of dockside sinkings is neglect - failing to maintain critical fittings and hoses that can flood a boat if they fail.
Adriance says you can't count on the bilge pumps to save your boat from catastrophic flooding. Water will flood through a 2-inch-diameter through-hull 4 feet below the waterline at a rate of 9,400 gallons an hour, and through a 4-inch opening at 37,780 gallons an hour - more than quadruple the rate of the smaller hole. "A bilge pump will help, but it's not going to keep a boat afloat unless it's a small hole," he says.
Here's some advice for keeping your boat afloat at the dock.
- Avoid adding through-hulls. If you must add one, be sure it is bronze or Marelon, properly installed and has a seacock that opens and closes if it is near or below the heeled waterline.
- Close all seacocks below the waterline if a boat will be left unattended at the dock or at anchor for a long time.
- Frequently check through-hulls, seacocks, hoses, clamps, shift bellows, stuffing boxes, sea strainers, mufflers and other fittings for corrosion, wear or leakage.
- If you're going to retrofit a system that will carry water through the boat, be sure it is engineered well, designed with high-grade marine materials and properly installed by boatyard professionals you know and trust.
- Check the yard's work to be sure it was done correctly.
- Be sure you have thought out what you want in your bilge pump array - which ones will handle nuisance water, which will respond to emergency flooding, how much capacity you want for each kind of pump, and whether they will kick in automatically or manually and operate off the batteries or require a running engine, a running generator or shore power.
- If you have watertight bulkheads, take advantage of them. Nordhavn's Jim Leishman says they are the best safeguard against catastrophic flooding. Don't breach their watertight integrity by leaving bulkhead doors open.
- Install an outside bilge alarm that is audible across the marina. Adriance says a loud exterior alarm and frequent inspections of below-the-waterline fittings are the best ways to curb dockside sinkings.
- Keep your boat at a marina with a guard who makes the rounds with some frequency and checks the boats.
See related article:
This article originally appeared in the June 2011 issue.