Comparison of Peak Discharge and Runoff Characteristic Estimates from the Rational Method to Field Observations for Small Basins in Central Virginia: Usgs Scientific Investigations Report 2005-5254 by Ricahrd L Young, John Miles Morrow, Donald C Hayes (Paperback / softback, 2011)
Various types of drainage structures are necessary to protect human life, highway settings, and the flood-plain environment from surface ruff. The design of a drainage structure requires hydrologic analysis of precipitation amount and duration, peak rate of ruff, and the time distribution of ruff from a given basin. Many hydrologic methods are available for estimating peak flows from a basin, and single method is applicable to all basins. The Rational Method is commonly used to estimate the design-storm peak discharge. The concepts of the Rational Method are sophisticated and considerable engineering kwledge is required to select representative hydrologic characteristics, such as time of concentration and ruff coefficient, which will result in a reliable design discharge. Validation of the Rational Method is difficult because direct measurement of some hydrologic characteristics, for example, time of concentration and ruff coefficient, is t easily accomplished.
Donald C Hayes, John Miles Morrow, Ricahrd L Young