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1.0 INTRODUCTION This report details the design procedure and hydraulic analytical methodologies utilized in the development of the South Branch of the South Fork of Little John Creek(SFLJC)channel relocation project. The relocation project involves moving a 3,200-foot reach of SFLJC to the south and west of its present alignment.The proposed alignment is shown in Sheet 1. The creek is being moved to accommodate the southern expansion of the Forward Landfill. The goals and objectives of the relocation project can be divided into three general categories: (1) provide riparian habitat restoration/creation to mitigate the filling a portion of Littlejohn's Creek from the southern expansion of the Forward Landfill; (2) provide adequate flood control (i.e. has capacity to carry the 100-year flow within its banks) in the realigned section of the creek; and (3) provide a stable channel design that meets or exceeds the functions and values of the existing creek. Thus the design goal is to create a channel that is as natural as possible and provides 100-year flood carrying capacity. Three main areas of investigation occurred to develop the design and are presented below include; 1) Existing Creek Conditions,2)Design goals and Objectives,3)Design Considerations,4)Hydrologic and Hydraulic investigations, 5)Relocation project description and 6)Maintenance Considerations 2.0 EXISTING CREEK CONDITIONS The existing south fork is a comprised of agricultural ditch traversing the southern border of the Forward landfill. The channel is 60 feet from top-of-bank to top--of-bank with an adjacent 15-foot maintenance road on either side for a total of 90 feet. 2.1 Habitat Conditions The existing creek has very little intact riparian habitat. Riparian vegetation is restricted to a very thin strip along the water's edge. Only ruderal and widely scattered riparian trees occur along the channel. The County Flood Control District routinely removes woody vegetation in this area. The channel does not have significant fish or aquatic wildlife. The Photos 1 and 2 show the existing creek channel. The relocation area is an upland area dominated by ruderal vegetation and some small eucalyptus trees. Photos 3 and 4 show the proposed new channel alignment. Questa Engineering Corporation 1 270124CDR/November 16, 2007