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0 levels, the realigned channel is expected to have 2.09 acres of open-water habitat and 0.88 acre of streamside wetlands, totaling 2.97 acres of waters of the United States; therefore, the long-term replacement ratio for waters of the United States is 1.1:1. This plan assumes that the design of the proposed creek channel mitigation also addresses San Joaquin County flood-control needs for the proposed landfill expansion. - This wetland mitigation plan is conceptual, providing guidelines for creek restoration and plant revegetation along realigned portions of Littlejohns Creek and, therefore, is not intended for use as a construction document. Design-implementation construction plans and specifications should be prepared by a qualified restoration specialist with proven experience in similar projects in both scope and magnitude. Conceptual Mitigation Plan Features To meet the goals and objectives for the proposed creek realignment, the design program incorporates three primary concepts: creating high-terrace riparian habitat on the floodplain, maintaining the flood-control function of the existing creek, and incorporating special requirements of governing agencies as outlined below. The proposed conceptual master plan drawing is included as Figure 3-2. Riparian Habitat Creation The primary mitigation concept is to create a 200-foot-wide floodplain with significantly enhanced riparian habitat value over that of the existing creek. The existing creek is a 46-foot-wide trapezoidal channel with minimal habitat value. No riparian habitat is present because the vegetation is cleared by County flood-control crews to maintain channel flows during flood events (Fukumoto pens. comm.). With the introduction of native riparian plants and grasses appropriate for this region. the proposed floodplain habitat should be able to sustain itself in perpetuity. The proposed riparian habitat is divided into two ecological planting zones (Figures 3-3 and 3-4). In the higher floodplain elevations, oak woodland habitat will be created by planting native oak trees and native shrubs common to oak woodland (Table 3-1). In the lower floodplain elevations, cottonwood-willow riparian woodland will be created by planting Fremont cottonwood, native willows, and native vines (Table 3-1). Prior to planting the woody vegetation, an understory of native grasses and forbs will be established on the floodplain- The total area of riparian habitat to be created is 39.4 acres. Although the creek will still exist in the context of an operating landfill,the mitigation plan has added features to maintain habitat integrity and buffer that habitat from the landfill operations. The existing channel has dirt roads above the floodplain and immediately adjacent to the both sides of the channel for access during channel maintenance activities (Figure 2-4). The realigned creek will have roads similar in character but placed outside a much broader floodplain (Figures 3-3 and 3-4). Weriand Mit' g¢rion anal Mon iroring Plan for the Chapter 3. Wetland Mirigation and Moniroring Plan Ausrin Road landfrll Expansion. U.S.Arms Corps of Engineers File 1994(X7974 Cin of Sroc�kron 3-2 April S. 1946