How to build drains int odeck

I'm soon to be taking a 1968 Luhrs flybridge down to a bare hull- the whole boat! Anyways, one of the many questions I have is this- I plan to use ply glassed over for the cockpit decking, and I've seen some newer boats that have a neat sunken (maybe 1/4-3/8") rail along the outside of the deck, right where the gunnels meet the deck. The sunken rail runs to scuppers in the transom. I was wondering if I can replicate that with a router, without losing any structural integrity, maybe I can just put a bigger deck support (2"x2" instead of a 1"x2") to support the sheet a little further off the gunnel?

 

The best way would be to just lap the plywood (a second piece attached to the underside), along the sides of the cockpit to form the "waterways". In this fashion, you'd not lose any strength, as you would if you removed some material with the router method you suggested. Make sure you incorporate some "crown" (curve in the deck) so water will shed toward these waterways and out the scuppers. The deeper the waterway, the more effective they be at removing water while the boat is under way.

 

Thanks Par- that's one of the idea's I've been tossing around- along with a nice 45* angle cut into the edge of the top piece to allow a nicer look once glassed over.