I have 220 on my dock and only 3 wires are in the box. Red, White, and Black. They drove a ground rod in on the bank. We want to add 110 v light and recept. I know how to come off one leg fro the power but being that they did not run a ground from the main panel, am I to use the wire from the ground rod as my ground for the 110?

What does "I have 220 on my dock" mean?
A panel? Just a circuit?

If this is a panel as I suspect you have an older 3-wire feeder. The ground rod does not provide anything as far as the circuits go. The neutral will be bonded on the panel and serves as both neutral and ground. The ground rod is also required by code but serves other purposes.

Can you post a picture of the box or panel at the dock?
Without that it is impossible to tell what it is you have there.