How do I electrically ground my house when my water pipe is made of plastic?

EPMiller

If you live in town and have a municipal water supply, look closely at the meter and you most likely will find that the pipe that comes in from the street is copper. That is where you attach the ground. If EVERYTHING is plastic you are not required to ground to the plumbing. There are other technicalities but you did not provide enough information to know if they apply.

EPMiller

iamgrowler

You drive a copper clad rod into the ground and run a ground wire from the rod to the ground lug in your service panel.

That's the bare bones description, of course.

The number of rods, length of rod, depth driven, distance from footing, ground cover and gauge of wire can vary from location to location -- So it's always best to check with the local authority to determine exactly what their expectations are.