said by GenNewbie :
Could I attach a ground wire from the gen to the thick braided cooper jump wire that is jumping the 2 pipes coming out of the hot water heater? I assume that is a grounding wire? It is accessible and since there is no sheathing and it is right near the same basement window, if it safe, it would be convenient. Thanks!
That new jumper was installed to prevent electrically isolating the hot water piping from the cold, that's all. The cold water side SHOULD be bonded to the breaker panel's ground bus, but it may not be unless you can see that it is. Any plastic pipe or dielectric fittings between that water heater jumper and any panel bond will disrupt that connection, too.
I'd stick with an electrical ground, not the plumbing system.