Object-GAWSER
Object-Oriented Guelph All-Weather Storm-Event Runoff Model
Phase I: Training Manual
Application of Object-Oriented Simulation to Hydrologic Modeling
JOHN A. HINCKLEY, JR.
INTRODUCTION
Object-GAWSER is a temperature index snowmelt model that can be used to demonstrate water-
shed hydrology. Object-GAWSER is best suited for agricultural or forested watersheds, but can be
used to demonstrate the hydrology of other types of watersheds, such as urban or suburban water-
sheds. Because Object-GAWSER is applicable to watersheds with different levels of development, it
can be used to show the effect of development on the hydrology of watersheds. For example, to
observe the hydrologic impact of forest clearing for agriculture, Object-GAWSER can be pro-
grammed to simulate the hydrology of a forested watershed and then reprogrammed to simulate the
hydrology of an agricultural watershed. One can examine the behavior of various hydrologic pro-
cesses such as runoff, infiltration, baseflow, etc., for each watershed. Object-GAWSER was created
using STELLA II, an object-oriented programming language, which allows users to observe the flow
of water on the computer screen via animated objects, graphs, and tables (Richmond and Peterson
1994).
History of Object-GAWSER
In 1977, Hugh Whiteley and S.R. Ghate of the University of Guelph in Ontario, Canada, created