water pipe as ground how much is needed
 

I got a bad leak on my 60+ year old pipe in from the meter
so want to replace the steel 3/4 inch now down to less then 1/2 line with a 1'' PVC line
how much steel line in the dirt makes a good ground of the electric service ?
I plan on leaving about 18 ft of steel as it is under a concrete slab
but not having a direct connection to the main water pipes as the PVC is not a conductor
do I need to run a wire to ground to the supply pipe or is the existing 18 ft sufficient
for grounding my house ?

New home service has 2 grounds. a 20' rebar in the footing, and 2 ground rods (5' each?)

Water lines, water heaters, etc. should also be connected with bonding wire. Use something like this: https://www.homedepot.com/p/Blackburn-Bronze-Ground-Clamp-1-2-1-in-for-Direct-Burial-JD-B1-15/202907610

Can you re-run the 18' over head or in a wall instead? Concrete and steel don't get along, especially in southern florida.

Traditional ground rods are about 8' long - and most homes use two of those - from what I have seen.

I'm no electrician so someone else can post more and better info, I'm sure...

I would drop a ground rod where the power comes in and run another wire to it from the main panel. I doubt you have a disconnect outside. (new code). or run it to the meter base. have pwr company open it up for you.

have ground on the panel to the steel water pipe
and another by the A/c outside and one for the att phone cable and internets
the last two are just bars driven into the dirt
the panel ground is a couple of feet inside the garage so connected to 20 ft of 3/4 pipe in the ground under a slab then new PVC pipe to the meter and main water lines

is the 20 ft of pipe enough for a good ground for the el panel ?

A ground rod is $13 at Home Depot. Buy one and forget about the steel pipe.

https://www.homedepot.com/p/ERICO-5-8-in-x-8-ft-Copper-Ground-Rod-615880UPC/202195738

ODD THOUGHT

is the water in a nonconductive pipe a ground ?

10' of water pipe in ground
two 8' ground rods, minimum 6' apart
20' of rebar in your footing
tie all the grounding together or you make the problem worse
use #6 wire

I have only one copper ground rod on my service. My outdoor disconnect and my main panel all tie to that single copper ground rod. I'd check code in your area and devise a plan from there. If you can use a ground rod, I'd run a copper ground wire out to it and call it a day.

No.

Best
Les

Yes, combined with the driven rods you have. Tie all of them together with #6 and the clamp I linked to before.

Instead of leaving 18' of steel line under a concrete slab why not drill under the slab to replace the 1/2 blocked line that you are using now with a clean clear line? Lots of videos on YouTube on how to do this. At some point that galvanised pipe will block completely or rust thru. Why only do 1/2 the job and then have to redo it again in a couple years?

When I built a house in Ontario the regulations called for two ground rods 6' apart. If I was building on solid rock I could attach the ground wire to both ends of the rods and lay in a shallow trench with 6" of covering overtop. Basically 22' of ground wire buried with the rods attached. I built on sand and was able to drive both rods into the ground with a sledge hammer. Here all is required is the ground wire is attached to the supply side of the water meter line.