Evaluation of Regional Storage-Discharge Parameters from Recession Analysis

Subsurface storage and discharge are important components of watershed behaviors to rainfall-runoff responses. The current representations of subsurface-surface relationships are poor in land surface models; such poor representation limits the application of land surface models to evaluate current and future conjunctive water management scenarios. The aim of this research is to derive storage-discharge relationships using streamflow recession hydrograph analysis for watersheds located throughout California. Regression analyses are performed to evaluate empirical storage-discharge parameters as a function of physical watershed parameters and catchment hydrologic characteristics. We illustrate how such regional empirical evaluations provide functional relationships consistent with historic literature to develop parameters for surface-subsurface interaction in fine-resolution land surface models for California.