SR 06:060 - Laserfiche WebLink

Ms. Kerry Sinnott 3909 Vineyard Avenue 10 November 2005 Page 2 'DeadweI1&RoI1o PROJECT DESCRIPTION The storm water outfall system wiIl include installation of an 18-inch-diameter pipe that will drain into the creek channel towards the north and daylight at the toe of the slope at approximate elevation 341.5 feet (City of Pleasant on Datum), An energy dissipation system will be installed down slope of the outfall consisting of a concrete channel filled wi\h rip-rap. The dissipater will have a minimum width of three feet and total length of approximately 20 feet. Specifications for the storm water outfall will conform to regulations set by the Zone 7 Water Agency of the Alameda County Flood Control and Water Conservation District.. . . To control erosion above the pipe outlet and either side of the energy dissipater, permanent turf reinforcement mat from North American Green will be installed from the crest of the slope to the tennination of the energy dissipation system. A minimum width of 10 feet ofturfreinforcement mat will be used. To control the maximum storm water flow rate from the outfall pipe, the pipe will be choked off at the nearest storm sewer manhole. Installation of the pipe will require a trench excavation of up to approximately 13 feet deep. It is our understanding that the slope geometry of the creek ch31Ulel will not be changed from the existing conditions. SCOPE OF SERVICES As outlined in our proposal dated 10 March 2005, our geotechnical services consisted of performing field exploration and engineering analyses to develop conclusions and recommendations regarding: . . soil composition and groundwater depth at the site . design parameters for the storm sewer outfall . slope stability analysis of static, dyamic, and rapid drawdown conditions . stability of the adjacent creek bank . construction considerations. During the course of our work we consulted with Civil Engineering Associates, Inc" the project civil engineer,