I've got close to a mile of black plastic water line running to 9 (need to put in 3 more) tire tank waterers, gravity-flow fed(siphoning, for all intents) out of an upland pond. probably anywhere from 40-60 ft of drop from the pond to where the waterers are. 1.25" pipe running down through the woods to the top of the pasture, necking down to 3/4" for most of the runs out/down to the tanks.