Section 32 Program. Streambank Erosion Control Evaluation and Demonstration. Work Unit 2. Evaluation of Existing Bank Protection. Field Inspection of the Mill Creek Midfloodway Gabion Barrier in the Los Agneles District

摘要

On 6 August 1979, the U.S. Army Engineer Waterways Experiment Station (WES) Section 32 Program evaluation team inspected the existing site at mile 2.5 on Mill Creek, near Mentone, Calif. Mill Creek is a left-bank tributary of the Santa Ana River, which flows into the Pacific Ocean near Huntington Beach, Orange County, Calif. The Santa Ana River-Mill Creek confluence is near Mentone, approximately 5 miles northeast of Redlands in San Bernardino County, Calif. The rugged mountainous watershed of Mill Creek has an area of 52 square miles, bounded on the north by the San Bernardino Mountains, on the east by the San Gorgonio Mountains, on the south by the Crafton Hills and Yucaipa Ridge, and on the west by the Santa Ana River. Elevations in the watershed range from 1,700 ft at the confluence to nearly 11,500 ft at San Gorgonio peak. The streambed gradient of Mill Creek in the vicinity of the site is approximately 4 percent (210 ft/mile).