These basins are used to retard flood flows in the urbanized area downstream of Carbon Canyon Dam.

The Carbon Canyon Diversion Channel serves to relay water from the Miller Basin Complex to the Santa Ana River.

8455, approved 22 June 1936), provided in part for the construction of reservoirs and related flood-control works for the protection of metropolitan Orange County, California.

In numerous subsequent conferences with the Los Angeles District (LAD) of the U.S. Army Corps of Engineers, the Orange County Board of Supervisors and OCFCD discussed the plan of improvement.

A comprehensive report on a plan for flood control in Orange County, California, was prepared by OCFCD in March 1955.

2, Santa Ana River Basin (and Orange County)", dated August 1957, submitted 21 February 1958, and approved with comments 17 April 1958.

This memorandum included design of the dam, outlet works, spillway, and a concrete-lined channel 4,080 feet (1,240 m) in length (see para.

Construction of the Carbon Canyon Dam started in April 1959 under contract DA 04-353-CIVENG-59-144, with work completed and accepted by the U.S. Army Corps of Engineers on 9 May 1961.

These basins are occasionally used to infiltrate water; however, their main purpose is to reduce floodflows in the area downstream from the Carbon Canyon Dam.

The lowlevel weir at the south end of the basin acts to restrict and divert flows to the Santa Ana River via the Carbon Canyon Diversion Channel.

Release rates from the dam are not to exceed the downstream capacity of Carbon Canyon Channel between the outlet works and Golden Avenue.