Unit Graphs for Nonuniform Rainfall Distribution

Correlation between Snyder's basin constants Ct and 640 Cp and basin physical characteristics of drainage area, total length, average slope length to the center of area, and elongation is established using synthetic data. Actual data are used to compensate for discrepancies introduced through initial use of synthetic data. Effects of nonuniform rainfall distribution on the basin runoff hydrograph is represented by a unit graph, selected from three computed for each basin. Computation formulas are presented to define each of the three basin unit graphs. A dimensionless unit graph is introduced for a more accurate definition of the rising and falling links of each unit graph.