In this section you will find informational resources including online maps, reports, manuals, and links to County Standard Plans and other government resources. Reference Materials (in PDF format)
- Master Plan of Arterial Highways (MPAH)
Find links to the Orange County Transportation Authority’s Road Master Plan, covering freeways, arterial highways and local streets - Orange County Highway Design Manual (HDM)
Find information on design standards for County highways - OC Public Works Standard Plans
Find Standard Plan information pertaining to County projects - Orange County Local Drainage Manual
Find computational techniques and criteria for estimation of drainage runoff, discharge and the design of drainage systems built for dedication to the Orange County Flood Control District - Orange County Flood Control District Design Manual
Find computational techniques and criteria for estimation of drainage runoff, discharge and the design of drainage systems built for dedication to the Orange County Flood Control District - Caltrans Standard Plans
Find links to County, other governmental and non-governmental Standard Plans & Specifications. - OCTA Traffic Flow Map
Find detailed map of County streets, toll roads and State freeways showing daily traffic volumes - Orange County Traffic Manual
Find a compellation of specific guidelines staff utilize when conducting traffic safety investigations - Unincorporated County Bridge Index
Find list of County bridges by name and location - Addendum No. 1 to RDMD Standard Plans, 2006 Edition
Addendum No. 1 to RDMD Standard Plans, 2006 Edition - Five Percent Reports
Highway Safety Improvement Program “5 Percent Report” Requirement