A licensed electrical contractor I work with says running a ground wire from a recpt to a water pipe bonding with a copper strap is an approved method for obtaining a ground from a 2 wire system. Example: knob and tube wiring, he ran a #12 wire from the recpt to a water pipe (3/4 galv) to acheive a ground. I argued with him since it was my belief this was not an approved method.

Please shed some light please. I have a 2002 NEC. Please reference some code so I can better understand, also a suggested approved method if his is not.

The local is Sacramento, CA In city limits.

Thank you
Jon