Contents: Outlet Works; Emergency Action Plan; Resource Use Master Plan; Inundation Study; Embarkment and Roller Compacted Concrete Dams; Sediment Transport Study. (fr).

Seven Oaks Dam, located 8 miles northeast of the city of Redlands in San Bernardino County, will be an earth and rock fill structure with a height of 550 feet above the existing streambed, crest width of 40 feet, crest length of 2,980 feet and crest elevation at 2,610 feet NGVD. The upstream and downstream slopes will be 1 vertical on 2 horizontal. The dam will have a storage capacity of 145,600 acre-feet at the spillway crest elevation of 2,580 feet NGVD. (FR).

This volume contains hydrologic information in support of the general design consideration for Seven Oaks Dam, Prado Dam, Santa Ana River mainstem between Seven Oaks Dam and Prado Dam, Mill Creek levee, Oak street Drain, Santiago Creek, and lower Santa Ana River. (FR).

The recommended plan for Oak street Drain consists of a concrete channel beginning at the existing Oak Street debris basin and extending over 3 miles to the confluence with Temescal Wash. The channel is designed to provide 100-year level of protection. Total project first cost is estimated at $20,652,000. The economic data for the project is contained in Volume 9, 'Economics and Public Comment and Response.' (FR).

The recommended improvement to the existing flood control Prado Dam, which was completed by Corps of Engineers in 1941, consists of enlarging the reservoir capacity by raising the spillway crest 20 feet and the top of the dam 28.4 feet to elevations 563 and 594.4 feet, respectively. A new gated outlet structure capable of releasing 30,000 cubic feet per second, an auxiliary dike, and a dike along the Corona Expressway would be provided. Approximately 1,660 acres of land up to elevation 566 feet would be acquired for the enlarged reservoir. Interior dikes would be provided for the protection of the existing facilities at the Corona Sewage Treatment Plant, Alcoa Aluminum Plant, Corona Housing Tract, and California Institution for Women. The cost for the recommended improvement is estimated at $212,623,000, including $116,274,000 for land acquisition. (fr).

Contents: Geotechnical; Coastal Design; Sediment Transport Analysis; Recreation; Side Drain Tabulation (Storm Peak Discharges). (FR).