A note on bilge pumps and holes. This isn't scientifically calculated, nor a C-Dory, but...
I was on a ~40 foot powerboat (not mine) that suddenly developed a ~3" diameter hole a foot or so below the waterline at the transom. It was noticed pretty quickly as the boat began to list and water began to fill the cockpit. It overwhelmed whatever bilge pumps were there (I don't know exactly what that setup was), then overwhelmed a portable gasoline pump, then nearly overwhelmed two 800 gph pumps the Coast Guard put aboard (granted, it took a few minutes for all these to be deployed).
The boat was saved with a combination of all these pumps and a side tie to the CG vessel (plus as I remember it we finally figured out where the hole was and were able to stuff something into it). The CG limped us over to a nearby Travelift where the boat was hauled and proceeded to "drain" overnight.
Anyway, all that just to say that with any "real sized" hole beneath the waterline, I would guess that most folks' installed bilge pump setups would not keep up with it.
On the other hand, as Martin says, access to the hull and a plug can work wonders. On another boat (also not mine, and I swear it's not me!) we were sailing along 150 miles or so from shore, and noticed a thin line of water seeping out from under the sink cabinet in the head. Opened the cabinet and ... "hmm, seems to be coming from that tranducer through-hull..." Reach over to touch through hull and.... it comes off in the skipper's hand! Now we have a ~1.5" hole leading to azure blue water that's around 2' below the waterline (interestingly, water did not "geyser" in, but just flowed in quickly. Run for the wooden plugs and hammer (located in specific, dry locker), pound one in, and along we went. Barely took on any water.
It was over a month before we were able to get to a facility to haul, and during that time no water came in at all around the plug. In fact, we had some work to get the darned thing out once we were on the hard! (A dry softwood plug swells when you install it.)
Naturally, that transducer through hull was the one job the boat owner had "outsourced" because it was early on and he wasn't confident he could do as well as the professionals (turns out it failed due to installation issues).
Of course all "holes" would not be tidy and round.... there are just so many variables.
A watertight bow compartment could be one measure; on the other hand, access to the hull is a good thing too. Seems like each choice has its plusses and minusses. My bow compartment is "stock" at the moment, but I think I'm probably going to install access lids and then leave the area accessible (and use it for light/bulky stowage). Just one way to go about it.
Sunbeam