Alluvial Fan: Proposed New Process‐Oriented Definitions for Arid Southwest

Abstract

The Flood Control District of Maricopa County, Arizona, recently completed a study whose purpose was to select and describe four alluvial fans for instrumentation and long‐term monitoring. One primary result of this study was the development of new technical, process‐oriented definitions to describe and differentiate among the types of alluvial fans found in central Arizona. These alluvial fans, while exhibiting the generic, regulatory fan shape, are subject to different types of hydraulic processes. Tables identifying the characteristics and hydraulic processes on each type of landform found in the study area were also developed. These new definitions provide a framework for engineers and regulators to discuss landforms with a common terminology that is tied to the relevant expected hydraulic processes.