grounding without a rod?

Except for corrosion problems, that might be cleverly overcome, it seems that you have an ideal situation. Run your grounding rods vertically along your pilings. I do not know what your code requires.

Bill

-- Ferme le Bush

You can obtain sectional ground rods through any electrical supply house. Simply assemble a rod that is long enough to reach the bottom of the water next to a piling and drive it in at least eight feet deep.

Alternatively you could locate the service on shore and supply the buildings lighting and appliance panel with a four wire feeder in the same way that manufactured buildings are often supplied. This second method reduces the likelihood of stray current that can parylize a person who winds up in the water next to the structure. Swimmers have been drowned by the paralyzing affects of stray current leaking from mis wired shore line connections on boats.

Thanks for your input. You guys have solved my problem.

A common grounding electrode method used in Southeast Alaska for sea water harbors is to run a bare copper grounding electrode wire into the water. Simple as that! No ground rod required!

The local code here in (this part of) Ky requires that you attach the ground wire to the re-bar in the buiding's concrete floor or footer. (I know that doesnt apply with your situation.) I think I would go with the ground on the beach, and 4 wires running to the structure, because of the possibility of someone coming into contact with stray currents while swimming. Of course your best solution would be to call the power company or the local inspector and see what method is required. They are the guys you have to please.