Tim,

If your in California it probably does not have to be very deep. Is this an irrigation pipe which would be drained? or is this a continuous pressure supply pipe for something? It only needs to be below frost depth I would guess 12"-18" but you should always check with your AHJ local Authority Having Jurisdiction, the Plumbing inspector or building inspector.

Hope that helps,

Dan

"I want to run a water line up close to the house. How deep is the run supposed to be?"

Depending on your location anything from a few inches in southern Florida to many feet in Minnesota.

Per code the line must be a minimum of 12" or 6" below your average frost line, whichever is greater.

Sorry about that. I didn't think about frost line living in San Diego. I will bury it 12 inches deep. I should be good with that. Thank you for your responses.