Yavapai County Drainage Design Manual

Yavapai County has been working on a new drainage and floodplain design manual since 2013, with the intention of replacing the existing Yavapai County Drainage Criteria Manual with a more detailed, comprehensive document that provides better guidance to the engineering and building community. This effort has been managed by the Yavapai County Flood Control District with input from the Public Works and Development Services Departments, as well as from the private engineering community. The existing 1998 Drainage Criteria Manual was last updated in 2005, and could benefit from improved guidance and details necessary to help properly support the design of drainage infrastructure and development in and around flood hazard areas, as well as to reflect advances in modeling technology and techniques since then.

With the assistance of an engineering firm, Yavapai County decided to take an existing document that has proven to be successful in Mohave County, and modify it to reflect the conditions and requirements of Yavapai County. With the support and permission of Mohave County, the Yavapai County Flood Control District obtained a copy of their Drainage Design Manual, and throughout 2013, held several meetings to discuss specific chapters and their applicability to Yavapai County. Modifications to the report resulted in a draft and subsequently final version of the Yavapai County Drainage Design Manual.

All drainage and flood hazard report requirements are remaining unchanged from the existing criteria manual. As mentioned, the primary purpose of this new document is to gather a larger compilation of technical information that can be presented to the engineering community and other interested parties. It includes more in-depth discussions of requirements and standardized methodologies as compared to the current regulatory document used by the Flood Control District. The Drainage Design Manual also includes example problems that were not provided in the Drainage Criteria Manual.

The report has gone through a review process internal to Yavapai County, as well as presentations to Prescott and Verde area contractor associations and engineers. Public hearings were held at the County Board of Supervisors meetings in Cottonwood on May 18th, 2015, and in Prescott on June 1st, 2015, at which time the Board passed a resolution to rescind the existing Drainage Criteria Manual and adopt the Drainage Design Manual. This change will become effective on July 1st, 2015, and all submittals after that date must follow the guidelines of the new manual.

Below are links to PDF versions of the Yavapai County Drainage Design Manual and its Appendices. If you have questions or comments, please advise the Yavapai County Flood Control District in writing via mail or email at web.flood.control@yavapaiaz.gov

Drainage Design Manual(PDF, 9MB)
Drainage Design Manual Appendices(PDF, 5MB)