On Grade Flow in Triangular Gutter Sections
Curb image

Modified Manning equation
(Modified Manning Equation) 		Where...
    Q = Channel flow in CFS (calculated)
    Z = Reciprocal of transverse slope (1/ST)
    D = Depth in feet
    S = Longitudinal slope
    N = Roughness coefficient at constant
        0.016 (value for concrete and asphalt)
Instructions
Alternate One Alternate Two Alternate Three
Depth of flow in feet (D):
Transverse Slope in ft./ft. (ST):
Longitudinal Slope in ft./ft. (SL):
Roughness coefficient (N): 0.016
(value for concrete or asphalt)		 0.016
(value for concrete or asphalt)		 0.016
(value for concrete or asphalt)
Total flow in cfs (Q):
Spread of flow in feet:

Catalog numbers and grate types that have K-charts:

Grate Coefficient from K-chart (K):
Grate capacity in cfs:
(Flow captured) (Flow captured) (Flow captured)





          For additional information regarding Neenah Inlet Grate Capacities, please contact
          our Product Engineer, Steve Akkala, at 920-725-7000 or at sakkala@nfco.com.