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I Draft Supplemental Environmental Impact Report Page IV.G-5 ' Forward Inc. Landfill 2018 Expansion Project developed portions of the Forward Landfill reach a maximum elevation of approximately 194 feet amsl. ' Surface Water Features The landfill property includes two local drainages,the North and South Branches of South Littlejohn Creek,which are within the Duck-Littlejohns Hydrologic Area and are tributaries to the San Joaquin River.The South Branch of South Littlejohns Creek currently flows east-west ' across the new proposed new south infill area, thereby requiring the re-routing of the creek to the south and then north to rejoin the old creek channel. Approximately 3,000 feet of the South Branch of the South Fork of Littlejohns Creek is to be relocated to the southeastern boundaries ' of the site in a new 3,400-foot channel to provide additional separation of the creek from the landfill. The project also would add a bridge crossing on the east side of the South Branch of South Littlejohns Creek as shown on Figure III.C32. The North Branch of South Littlejohns ' Creek was realigned to the north and west of the Landfill in 2002,in order to place its channel and floodplain outside the footprint of landfill areas. Flood Hazards ' The proposed expansion areas, including the South Branch of South Littlejohns Creek ' realignment at Forward Landfill are located within FEMA Flood Insurance Rate Map (FIRM) panels 0635F (October 16,2009).The south expansion area is within flood zone Flood Zone Designation X,which is an area of minimal flooding. ' Flood hazard areas along the North Branch of South Littlejohns Creek are mapped as confined within the relocated creek channel (San Joaquin County Flood Zone Viewer, accessed August 24,2018). The North Branch has been realigned to the north and west of the landfill fill area, ' and is now designed to carry the 100-year flood flows.The North and South Branches of South Littlejohns Creek on the site are subject to regular maintenance for flood control.This maintenance consists of clearing trees and shrubs from the banks and dense vegetation from the ' channel. A Central Valley Flood Protection Board encroachment permit with endorsement by the San ' Joaquin County Flood Control and Water Conservation District is required for any work within the channels or within 25 feet of the top of bank of the creeks, and the realignment of the South Branch must be approved by the Board.Questa Engineering Corp (Questa)has developed plans for the realigned South Branch channel.The new channel is designed to carry the 100-year flood flows within its banks. Erosion protection would be provided in areas with high velocities or sharp bends. Surface Water Quality The RWQCB Order R5-2014-006 requires quarterly surface water quality monitoring at four ' points on the landfill site,when surface water is evident.Two of the sampling locations,FSW-2 and ASW-1, are located upstream of the landfill and represents background conditions.The other sampling points,FSW-1 and ASW-2, are located immediately downstream of the landfill, I