I have a bit of a situation with my interior subpanel not being grounded properly.
The interior subpanel does not receive a ground wire from the main service panel where it is grounded (to the water pipes where it enters the house), but it does have a ground wire attached to a seperate location on the pipe, and hence having that pipe act as it's ground path back to neutral at the panel. I'm wanting to install a surge protector at the subpanel, and this all seems a bit sketchy to me as that means that any surges would travel through the pipe, possibly electrifying them.
Would my proposed solution (in dotted line) be code legal and effective? I'm not able to open the main panel to to run a new ground wire as the finishing makes it inaccessible, and would require removing the meter (which is of course locked down).