), a hydraulic slope "S" = 0.01 (1%) is reached at a flow rate "Q" = 157 lps (liters per second), or at a velocity "V" = 2.17 m/s (meters per second).The following table gives Reynolds number Re, Darcy friction factor "f""D", flow rate "Q", and velocity "V" such that hydraulic slope "S" = "h""f" / "L" = 0.01, for a variety of nominal pipe (NPS) sizes.