My suggestion rather than these web cams would be to install two bilge pumps along with an alarm console. Their not expensive.
What you have in mind I think would require your computer to be on all the time or they can't
record to anything. If your intent is to see places when your under way and sailing, then I really don't see that as necessary. If it is necessary, then 'whoa'! why? where's the hole?
The two inexpensive bilge pumps you put one down low and then above that one you put a second. There are basic instructions in the alarm console packet at how to wire it. The idea is that if the 'lower' bilge switch fails to turn on, then the second switch goes off when the
water reaches it, along with an alarm. So if your sleeping, you will get a rude awakening.
You can also set up a little diode on the circuit with a cheap little LED light that if the top alarm goes off when your on your
mooring, the light comes on and stays on until you reset it. That way when your away from your
mooring and the second higher bilge went off and empty's the bilge, you will know it happen and can then go looking as to why that happened.