On Sep 28, 8:06 am, (Doug Miller) wrote:
And now you've gone and gotten it wrong again. Metal water pipe is *required*
to be used as a grounding electrode. You said it's not. That's not true.

Code only requires water pipe must be bonded. That 'bonding' to
remove fault currents from pipes. Code does not require water pipe to
be used as an earth ground. However code is written so that a water
pipe may also be an earthing electrode - albeit insufficient. If
water pipe is used as an earthing electrode, that still in not
sufficient to meet code requirements for earthing as stated in article
250.52(D).

Earthing must be provided by any one of items listed in article
250.52(A) paragraphs two through seven. Paragraph one defines how a
water pipe might be an earthing electrode. Code requires any one of
those other earthing electrodes - in paragraphs two through seven - to
exist. Code says an earthing electrode must exist AND lists the only
valid six electrodes that meet that requirement.