A Modified SCS-CN Method: Characterization and Testing Academic Article uri icon


  • The Soil Conservation Service Curve Number (SCS-CN) method (SCS, 1956) is modified by accounting for the static portion of infiltration and the antecedent moisture. A volumetric analysis shows that the ratio of the potential maximum retention (S) to the precipitation amount versus the runoff factor relation is equivalent to the average suction pressure-moisture content relation for a unit rainfall amount and a given soil porosity. A simple spreadsheet procedure is suggested for determining S with use of a 5-day antecedent precipitation amount. The modified method is found to perform well on the same data sets as used in the National Engineering Handbook (SCS, 1971).

author list (cited authors)

  • Mishra, S. K., Singh, V. P., Sansalone, J. J., & Aravamuthan, V.

citation count

  • 56

publication date

  • February 2003