The 1986 Orange County Hydrology Manual and its 1996 Addendum have been calibrated to local watershed conditions. They provide guidance in estimating peak discharges and volumes of storm water runoff…

Safety & Education Introduction Brochures BE FLOOD READY! Flood Safety & Awareness Visit the Be Flood Ready!  web page. Download a PDF of the Be…

Geotechnical Design Report Revised Aerially Deposited Lead Report Material Report Aerial Deposited Lead Report

What are OC Road Fees? OC Road Fees are fees that are imposed by the County of Orange on new development projects, to pay for a portion of construction cost or needed expansion of offsite…

Core Services One of the County’s primary objectives is to provide our community with a safe and efficient unincorporated roadway system through the planning, design, construction and maintenance…

Project Background You asked. We listened. OC Public Works will revitalize and activate the vacant parcel to transform the underused space into a viable commodity for the neighborhood to enjoy…

When the SARI Line was completed in the mid-1970s, the pipeline was buried with as much as 20 feet of soil cover in some locations. Over the years, the riverbed has eroded and now provides only 1-…

The City Engineers Flood Control Advisory Committee (CEFCAC) was formed in August 1966 to provide cooperation between the Orange County Flood Control District (OCFCD) and the cities toward the best…

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)…

The County of Orange has six active OC Road Fee Programs.  Each OC Road Fee Program has a specific Area of Benefit (AOB) that determines if an OC road fee is associated with the…