Our well is underground and we're not sure where it is. We also don't know anything about the pump, other than it apparently works. We want to run water to the garden, which is about 500' from where the well comes into the house. We'd like to split off the main line. With some light researching, polyethlene pipe seems to be the product to use. What diameter pipe should we use to make the 500' run?

What size pipe is the supply from the well? Well is probably 1". No sense going any larger than the supply.

This 500 foot run, does it run uphill, downhill, or level? Do you know the size of the pump? How much garden area do you wish to irrigate? What pressure does the pump work up to before it cuts off? Any more details you can give us? Back to you, Tom