option that I looked into, but did not go for is shown at; http://yachtwork.com/product-bilge.htm

It sure looked like it would work on a number of levels! And pumps a LOT of water!!! It looks like you just start the diesel and ........

From the site....
The prop shaft driven emergency bilge pump can easily remove vast quantity of water that a standard bilge pump simply can't.

For example, if there is a 4" hole in a vessel 2 feet below the water line, it will flood in at a rate of approximately sixteen thousand gallons/hour. That is almost three hundred 55 gallon drums of water per hour!

A small hole like this can sink a vessel in a matter of minutes. The smallest Fast Flow pump will pump 24,000 gallons/hour at 2,000 rpm.

Standard disclaimer, not connected.

Greg