Evaluation of Hydrologic and Hydraulic Procedures for Small Urban Watersheds in the Southwest

Abstract

Hydrologic and hydraulic design procedures developed by the Pima County Department of Transportation and Flood Control District were proposed for use by the Department of Transportation, Engineering Division of the City of Tucson, Arizona. These procedures were evaluated with respect to their reasonableness of approach and in comparison with other methods and existing data used to derive similar methodology and standards. The proposed criteria/methodology were found to be consistent with procedures used in other cities in the Southwest, and with the current state of the art in urban hydrology and hydraulic engineering practices and procedures. However, locally derived rainfall intensity -duration relationships were found to be superior to regionally based relationships, and minor modifications were suggested for channel design procedures.