from "Chow, V.T., Maidment, D.R., Mays, L.W., 1988, Applied Hydrology: New York, McGraw- Hill."

Manning's n Tables Manning's n values for Channels, Closed Conduits Flowing Partially Full, and Corrugated Metal Pipes.

Manning's n Table TxDOT Manning's n Table

Estimates discharge in US customary units from

Q = (1.0/n)*A*(A/P)^(2/3)*S^(1/2)

where:

Q is the discharge (cubic meters per second)

n is Manning's roughness coefficient (read from table)

A is cross sectional flow area (square meters)

P is wetted perimeter (meters)

S is friction slope (often the channel slope is substituted)

----- INPUT VALUES -----

Manning's n | Look-Up | |

Flow Area | (m^2) | |

Perimeter | (m) | |

Slope | (m/m) | |

----- COMPUTED RESULTS -----