In this paper we introduce the idea of parallel pipelining for water l
ubricated transportation of oil (or other viscous material). A paralle
l system can have major advantages over a single pipe with respect to
the cost of maintenance and continuous operation of the system, to the
pressure gradients required to restart a stopped system and to the re
duction and even elimination of the fouling of pipe walls in continuou
s operation. We show that the action of capillarity in small pipes is
more favorable for restart than in large pipes. In a parallel pipeline
system, we estimate the number of small pipes needed to deliver the s
ame oil flux as in one larger pipe as N = (R/r)(alpha), where r and R
are the radii of the small and large pipes, respectively, and alpha =
4 or 19/7 when the lubricating water flow is laminar or turbulent.