The existing concrete trapezoidal channel that was constructed in 1963 was considered deficient in its ability to convey storm flows due to extensive storm damage experienced in 1993 and 1995. The 4,000 feet of new improvements consists of the replacement of the damaged channel with a concrete covered channel between El Camino Real and Avenida Pico and a reinforced concrete rectangular channel between Avenida Pico and the upstream terminus of the project downstream of I-5 freeway. The Federal Emergency Management Agency (FEMA), through its Hazard Mitigation Grant Funding program, funded 75% of the project. OCFCD and the City of San Clemente through a cooperative agreement funded the remaining balance of the project. The project has water quality features including a debris boom and a low-flow water quality diversion structure that will allow future construction of a City-developed water quality diversion project.
The contract was awarded to Belczak & Sons, Inc. in 2003 for $5,742,493.