Approximately 11,000 miles of rivers, streams and washes run through Maricopa County. In order to enhance and maintain the benefits provided by these watercourses, the Flood Control District of Maricopa County engaged in an effort to refine its role in river planning and management. To develop an enhanced river planning and management strategy, District staff adopted a process called C3RPM. The core C3 process addresses complex issues with a blend of comprehensive information collection to solicit diverse opinions; a coordinated and deliberative assessment of that information; and a collaborative decision-making system free of bias to promote a consensus result.

Covers an area in southeastern Pima County that drains the Arivaca Creek watershed. The purpose of the report is to estimate peak discharge for the 50 year storm frequency event, utilizing the rational method (Q=CiA). This method pre-dates that outlined in the Hydrology Manual for Engineering Design and Floodplain Management within Pima County, Sept. 1979, and is considered less accurate. It is recommended that this report be archived and discontinued for use for regulatory purposes.