I am going to run a submersible pump in a well 600 feet from our cabin. It is going up hill probably 20 feet in slow rise. Would you have a low pressure by only going with 1" instead of 1 1/4" sch 40. Also another question - the existing line is one made of ~2" - ~2 1/2" plastic pipe which they use for water at oil drilling sites. I did not know this. I was thinking about digging down to the pipe from the top part of the attachment and running the new pipe inside of the old pipe. I was going to use bell ended pipe and use the beveled end going down hill so with any bumps it would slide over. The pipe is a single piece. What do you think the chance of running it inside of the other pipe all the way down.

I would opt for the larger pipe size in this case. As far as sliding the new pipe inside of the old pipe. All you can do is try. If it doesn't go, you need to dig a separate trench. Are you dead set on pvc. You could use black poly and it may slide through the existing pipe better

Is the black poly pipe better or cheaper

The black poly is cheap and has the advantage in that you can buy it in long lengths so no joints. However, it is my understanding that the black poly does tend to break down after years of use.

Just out of curiosity, why are you going to replace the pipe? Is the current pipe leaking? Just because it was designed for a different use doesn't automatically mean that it will not work well to supply your house with water.

Black poly is just as good as other tubing as long as you get the higher rated psi tubing and use brass (not plastic) fittings for adapting. I always use two hose clamps for each connection. Please let us know what you decide.

Glad you pointed that out. I'm not real familiar with black poly as it's kind of gone out of style around here.