| Symbol |
Definition |
| A |
area, m2 (ft2) |
| bc |
channel span across bars, m (ft) |
| Cd |
discharge coefficient |
| Ce |
dimensionless culvert exit head loss coefficient |
| C0 |
dimensionless culvert head loss coefficient (Ce+Ke) |
| d |
particle size of interest, m (ft) |
| Di |
particle size representing i% finer
(Example, D16 is the particle size representing 16% finer) |
| f |
dimensionless Darcy Weisbach friction factor |
| g |
acceleration due to gravity, m/s2 (ft/s2) |
| h |
bank height, m (ft) |
| HW |
headwater elevation above the culvert entrance invert, m (ft) |
| Ke |
dimensionless culvert entrance head loss coefficient |
| L |
length, m (ft) |
| ht |
critical bank height, m (ft) |
| n |
Fuller-Thompson coefficient for adjusting bed mixture gradation |
| n |
Manning's roughness coefficient |
| Q |
flow, m3/s (ft3/s) |
| q |
unit discharge, m3/s/m (ft3/s/ft) |
| qc |
critical unit discharge, m3/s/m (ft3/s/ft) |
| Q100 |
one hundred year flow, m3/s (ft3/s) |
| R |
hydraulic radius, m (ft) |
| S |
slope, m/m (ft/ft) |
| Sf |
friction slope, m/m (ft/ft) |
| V |
velocity, m/s (ft/s) |
| y |
depth of water, m (ft) |
| Z |
baffle height, m (ft) |
| τ |
shear stress, Pa (lb/ft2) |
| τc |
critical shear stress, Pa (lb/ft2) |
| γ |
specific weight of water, Pa (lb/ft2) |
| τ* |
dimensionless Shield's parameter |
| Φ |
angle of repose (degrees) |
