ABSTRACT

The Generalized Watershed Loading Functions (GWLF) model was originally developed at Cornell University by Douglas Haith and associates (Haith and Shoemaker 1987; Haith et al. 1992) as “an engineering compromise between the empiricism of export coefficients and the complexity of chemical simulation models” (Haith et al., 1992, p.1). The GWLF approach conceptualizes the watershed as a system of different land areas — hydrologic response units (HRUs) — that produce surface runoff and erosion and a single groundwater reservoir that supplies base flow.

Dissolved and suspended substances (i.e., nutrients, sediment)