Scupper drains

[JonnyBoats]

If one were building a new boat, what is the best way to design scupper drains?

The thing is, the idea of having scupper drains for the cockpit leading to seacocks via rubber hoses bothers me in that the seacocks must be left open when no one is aboard for the cockpit to drain. Assuming the seacock is below the water line and the hose should fail?.

Which I guess is why someone came up with the idea of fiberglass tubes to drain the water from the cockpit. I assume they felt fiberglass tubes were less likely to fail than rubber hose. Unfortunately without seacocks this is far from ideal should they fail.

Is this why so many modern ocean racing yachts have the rear of the cockpit open to the sea, eliminating the need for any sort of scupper drain?

Is there a better way?

[Tim]

So much depends on the design of the boat. Boats with higher freeboard can generally drain the cockpit above the static waterline; this is the best method. You almost never see scupper drains particularly high up in the hull because builders don't want the steady outflow to stain the topsides. That's one reason that the outlets are either hidden in the counter, or at/below the waterline.

The lower the freeboard, the lower in the boat the cockpit sole will be and the less likely it will be that the scuppers could be above the waterline. The sole in a Triton is almost exactly at the waterline--only an inch or three above. Frankly, I think the fiberglass tubes were all about saving time and production cost; you never see that sort of thing anymore in newer production designs. It was almost exclusively a 60s and 70s Pearson thing.

I'd feel better about the fiberglass tube concept if I thought the tubes were actually well fabricated and installed. I have yet to be encouraged by what I have seen when I remove any of the old Pearson tubes--they tend to be resin-starved and extremely weak. This goes for the old stern tubes, too. With a quality fiberglass tube, like those from Spartan or McMaster, and a solid installation, this technique might have some merit in some applications. I prefer true seacocks, but for tight confines like the scuppers on a Triton, there's something to the idea of the fiberglass tube.

All in all, I prefer an easy, effective way of shutting any through hull opening, even if those like scuppers remain open all the time.

I've always thought that you could run a pair of drain pipes or hoses, roughly horizontal, from the after end of a cockpit like that in the Triton; they would end up exiting high in the counter, above the waterline. With a foward-pitched cockpit, like in a Triton and many other boats, closing the original scuppers and leaving only the new after drains open would allow a small amount of water to collect during a rainstorm, but the open drains would prevent any significant amount of water from collecting.

The open transoms in racing yachts are more to reduce weight than anything else--both from the elimimation of that material and also from the elimination of the plumbing required for drains, but also do allow easy drainage of water. Open transoms are very functional in many ways and are good for race boats, but I don't think they allow for the cozy cockpit desired in a cruising boat.

[JonnyBoats]

Thanks Tim,

I've always thought that you could run a pair of drain pipes or hoses, roughly horizontal, from the after end of a cockpit like that in the Triton; they would end up exiting high in the counter, above the waterline. With a foward-pitched cockpit, like in a Triton and many other boats, closing the original scuppers and leaving only the new after drains open would allow a small amount of water to collect during a rainstorm, but the open drains would prevent any significant amount of water from collecting.

I really like that idea and feel to could make for a far safer boat.

I recently saw a survey ( http://www.oceanmarineservices.com/why_ ... s_sink.htm) that said 80% of all recreational boats that sink do so at the dock!

Of those (at the dock), 50% were thru-hulls below the water line and 32% water in self-bailing cockpits.

So basically there would be two large scupper drains in the cockpit connected by hoses to seacocks located directly under the scuppers (for nice straight hose runs), as well as two smaller drains leading to thru-hulls well above the water line?

When aboard one would open the seacocks to allow the cockpit to drain completely and when leaving the seacocks would be closed.

[Tim]

One thing I'm considering when I start my Seabreeze refit is to install an after set of scuppers (above the waterline), as I described above. Then, since the forward set of scupper drains would be below the waterline, I'm envisioning seacocks, perhaps with some cable-actuated (think engine control cables) remote controls, depending how inconvenient it is to reach the new seacocks. This may be overly complicated, but I'm giving it a little thought anyway.

I'm not surprised at the hose-failure sinking statistics, nor the sink-at-dock statistics. Neglect and lack of maintenance are almost always responsible for boat damage and sinkings. Why risk a boat over a few hoses? Replace them all every several years. And use the best hose clamps, too (yes they cost more, but are worth it).

One thing to consider with the after drains and closed seacocks is that any deck fittings in the sole, such as access hatches, etc., must be entirely waterproof for the system to succeed. If these hatches allow water into the bilge, the whole thing might create a far worse problem than leaving seacocks open in the first place.

[JonnyBoats]

One thing to consider with the after drains and closed seacocks is that any deck fittings in the sole, such as access hatches, etc., must be entirely waterproof for the system to succeed. If these hatches allow water into the bilge, the whole thing might create a far worse problem than leaving seacocks open in the first place.

Would you consider hatches which allowed green water to flow into builges safe on an offshore boat?

[Tim]

Of course not... but many do anyway, sometimes unbeknownst to their installers. There are too many corners cut by individuals and manufacturers to assume anything.