Versions Compared


  • This line was added.
  • This line was removed.
  • Formatting was changed.

The Santa Barbara Urban Hydrograph method is described in this document from the Washington State Department of Ecology (section 2.3.3), with the input attributes described below.

This method may not be available for your region. For more information, refer to the Regionalisation topic.

Pervious Curve Number - The runoff curve number for the pervious fraction of the Catchment, as described in National Engineering Handbook - Section 4 (NEH-4) Chapter 9. Typical values vary from 20 for areas with high infiltration and interception capacities to 98 for impervious areas. It is a dimensionless number depending on hydrologic soil group, cover type, treatment, hydrological condition, and antecedent moisture conditions. This number has a valid range from 0 to 100 with typical values from 60 to 90 and 98 for impervious surfaces.