mirith:
You could always order something like: http://www.omega.com/googlebase/product.html?pn=LA-13&gclid=CL-ptZGW2b0CFS1eOgod_i4AcQ
I actually do have those. I'd like to put an Arduino there also so I get notified via internet 
It seem simple enough to put in two wires to sense water, but the more I thought about it the more doubts I had. I'll have to try it out.