A statistical mechanical prediction of the dimensionless unit hydrograph

That the form of the dimensionless unit hydrograph is very nearly independent of watershed properties implies that it should be predictable with a minimum use of such properties. Such a prediction is formulated in this study, using Boltzmann statistics. The prediction shows that a characteristic time is the only important watershed property and that the shape of the watershed has only a minor influence on the form of the hydrograph. The resulting theoretical hydrograph is compared with observations made in two watersheds and is found to represent them well.