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Hydrology:  

Tc - Channel Flow
  • Time of concentration (Tc) for stormwater runoff in channelized flow or shallow concentrated flow using USDA, NRCS, TR-55.
Tc - Overland Flow (kinematic wave formula)
  • Calculate the time of concentration (Tc) for overland flow across small areas without defined channels using the kinematic wave formula.
Tc - Overland Flow (kinematic wave formula)
  • Calculate the time of concentration (Tc) for overland flow across small areas without defined channels using the kinematic wave formula.
Tc - Overland Flow
  • Calculate the time of concentration (Tc) for overland flow in shallow concentrated flow across an area.
Rainfall Intensity
  • Calculate the rainfall intensity (I) for different storm frequencies using the Steel formula.
Rational Formula
  • Calculate the stormwater peak discharge (qp) using the Rational Formula.
Rational Formula Runoff
  • Calculate the stormwater runoff (Q) using the Rational formula peak discharge.
Rational Formula Detention Storage
  • Calculate the stormwater detention storage volume (Vs) using the Rational Formula Hydrograph Method.
Modified Rational Method
  • Calculate the stormwater peak discharge (qp) using the Modified Rational Method.
NRCS Runoff
  • Calculate the USDA, NRCS, TR-55 runoff rate by curve number method.
Composite CN - Connected Impervious Area
  • Calculate USDA, NRCS, TR-55 composite Curve Number for area with a connected impervious area.
Composite CN - Unconnected Impervious Area
  • Calculate USDA, NRCS, TR-55 composite Curve Number for area with a unconnected impervious area or total impervious area less than 30%.
Travel Time Average Velocity
  • Calculate the average velocity for shallow concentrated flows to calculate the USDA, NRCS TR-55 travel time or time of concentration.
Graphical Peak Discharge Method
  • Calculate peak discharge using USDA, NRCS, TR-55 Graphical Peak Discharge Method.
Tabular Hydrograph Method
  • Calculate the USDA, NRCS, TR-55 runoff rate by curve number method.
NRCS Runoff Volume
  • Calculate USDA, NRCS TR-55 stormwater discharge runoff volume to use in detention basin storage volume calculation.
SCS Detention Volume
  • Calculate detention storage volume for difference between the post development discharge and predevelopment discharge using SCS detention volume method.
Design Problem 1
  • Given a 600'x600' rural parcel of pasture land located in Region 1, determine the 10 year stormwater discharge to size a culvert that will be located on the SE corner of the property. Use the Steel formula and rational method to determine Q.
Design Problem 2
  • Using the NRCS method, determine the volume of stormwater runoff that must be stored in an onsite retention pond to meet local land development regulations for a 5 acre commercial development site.