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Draft Prospectus Document Page 4 07/07/2020 <br />Wetland boundaries are shown on Figure 2, Appendix A. Much of the site is existing, partially drained wetland. <br />There are small areas of upland at the far north and south ends of the site. <br /> <br />Project Plans <br />Thoroughly describe actions you will undertake to restore, enhance, or create wetland on your site. Support this <br />narrative with a simple drawing or sketch showing where these actions will occur (Figure 3). <br />For projects that preserve and protect existing high-quality wetlands, review the BWSR/Corps joint “Guidance on <br />Evaluating Potential Wetland Preservation Sites …” and briefly describe how your proposal could satisfy eligibility <br />requirements in the guidance. This document is available on BWSR and Corps websites. <br />Figures 3a and 3b, Appendix A display two options for hydraulic wetland restoration. The goal of this project is to <br />restore the historic hydrology of the currently drained historic wetland community, manage invasive vegetation <br />monocultures, and establish native vegetation in perpetuity. <br />Figure 3a, Appendix A shows Option 1, where the wetland hydrology would be restored by constructing 2-3 ditch <br />plugs in the western and central north-south lateral ditches. Ditch plugs consist of clay core trenches compacted <br />with construction-grade clay topped with topsoil and vegetation. Ditch plugs are keyed into the banks to prevent <br />water from moving around them at high flows. One ditch plug would be constructed at the intersection of the <br />eastern lateral ditch and the east-west main ditch channel. 2-3 plugs would also be constructed in the southern <br />ditch. An outlet control structure (OCS) with a set elevation would be installed at the southwestern edge of the <br />parcel where the ditch connects to JD 3. <br />Figure 3b, Appendix A shows Option 2. The western and central north-south lateral ditches would be filled. One <br />ditch plug would be constructed at the intersection of the eastern lateral ditch and the east-west main ditch <br />channel. One ditch plug would be constructed at the western extent of the south ditch. An OCS with a set <br />elevation would be installed at the southwestern edge of the parcel where the ditch connects to JD 3. <br />A number of steps must be completed prior to selecting once of these options. Topographic survey, hydraulic <br />assessment, easement encumbrance review, subsurface drainage assessment, and soil investigation. <br />As part of the hydraulic assessment a topographic survey will be completed in addition to subsurface tile review <br />and a soil investigation to determine if sandy subsoils are present below the organic soils on site. Hydrology <br />modelling will be utilized (in the prospectus phase) to determine existing conditions that include the scope and <br />effect from JD 3 on the wetland, as well as proposed conditions to determine where the ditch plugs can be <br />placed without causing adverse effects to upstream or downstream properties. Modeling data will be used to <br />design the ditch plug placement and the runout elevation at the OCS. <br />The project will restore historic hydrology to the site creating saturated conditions that are undesirable for <br />invasive species such as reed canary grass. Vegetation management will include a site-wide herbicide application <br />on invasives in the spring. Selected tree removal will also occur at this time in the wooded areas of the site to <br />eliminate invasive and nuisance trees. Another site-wide herbicide application would be completed during the <br />late summer followed by either a controlled burn or mowing in the fall. The site would be seeded with native <br />vegetation in the fall and supplemental plantings of trees and shrubs would be installed in the wooded areas. Site <br />construction would occur in late fall or winter following initial vegetation management to increase the amount of <br />water on the site and to create less desirable growing conditions for reed canary grass to reestablish. Post <br />construction, the city would continue vegetation management (herbicide applications, burn/mow, supplemental <br />seeding, etc.) in perpetuity to maintain the quality of the wetland bank. Bank performance standards and a <br />vegetation management plan will be developed during future phases of this project. The native vegetative