Use at your own risk.


Runoff calculation using Santa Barbara Urban Hydrograph routing method. Uses SCS curve number method for rainfall abstraction.


User can choose preset hyetograph or provide her own coefficients. The time of concentrated for the catchment is calculated using lag method. It depends on the slope and the flow path length of the catchment.



  1. Rainfall is not defined for duration greater than 24 hours.
  2. See Atlas 14 to get other geographical areas.


  1. Stubchaer, 1975
  2. Ladson
  3. Santa Barbara
  4. Innovyze
  5. XP Solutions
  6. SCS curve number
  7. Anticipated Update to SCS Curve Number
  8. Draft of update
  9. Ponce, V. M., Runoff Curve Number: Has it Reached Maturity?, 1996
  10. 2018 AUG 21 B. Shrestha

    2018 SEP 25 B. Shrestha