I did a similar thing a few years ago, and I ran my water line inside 2 1/2" schedule 40. I was running it under a gravel driveway and I didn't want to chance gravel damaging the line. I ran the PVC close to both ends and then pulled the 1" water line through with a rope. Just suck a bread wrapper through with a sting tied to it using a vacuum cleaner, and then use that to pull the rope through. On each end I capped the schedule 40 with a rubber cap fastened by stainless clamps. I just punched a hole in them for the water line. It was a big job digging the trench and replacing two sections of concrete sidewalk but now I can change the line in the future and only have to dig a hole at each end. Oh yeah...I used 45 degree fittings instead of 90s so there weren't any tight corners.

Last edited by reivertom; 11/20/19.