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city easement (the rest of the pond is located on private property). It should be noted that only dredging a portion of a pond will likely lead to redistribution of the accumulated sediment from other portions of the pond over time and the entire pond will still require dewatering to perform the work. Braun Intertec completed pond sediment sampling from the ponds to characterize the in -place sediment (future dredge material). These sediment samples were tested and evaluated in accordance with Minnesota Pollution Control Agency (MPCA) standard procedures as described in Appendix B of Managing Stormwater Sediment BMP Guidance for Municipalities. Based on analytical results from the sampling and testing, excavated stormwater sediments from the identified ponds fall within the Residential/Recreational SRV management category and may be used with no restrictions. To determine the volume of accumulated sediment, a bathymetric survey was completed for each of the stormwater ponds. This process involves taking measurements at various locations throughout pond to determine the top of sediment and then pushing through the sediment to the approximate original pond bottom. The difference between these measurements provides an estimate of the accumulated sediment volume to be dredged out of the pond. Similar to the backyard storm sewer improvements identified above, access to these ponds is anticipated to necessitate tree removal and restoration of temporary access impacts, including private landscaping facilities in some areas. See Figure 1 in Appendix A for the proposed project layout identifying the limits of each proposed pond dredging operation. Sediment sampling and an associated report of its findings were completed by Braun Intertec for the ponds and the report is included in Appendix E F. Trails The public and City staff identified additional trail and retaining wall scope through the feasibility study process that should be considered for addition to delivery of this project. Upon review of the existing poor trail conditions, their location, and type of work necessary to make improvements, it is recommended the improvements of trails adjacent be added to the originally proposed and related street improvement scope of the project. The proposed trail improvements include removal of the existing bituminous pavement and repaving the trails with new bituminous on the existing aggregate base materials. Additionally, the trails will have new concrete pedestrian ramps installed where the trails proposed for rehabilitation intersect roadways in the project area. Beyond the pedestrian ramps, the trails are proposed to be replaced, in kind, matching the existing trail alignments, widths, and elevations. Due to the existing site topography, some segments of these existing trails appear to be quite steep and may not be feasible to improve to strict compliance with Americans with Disabilities Act (ADA) requirements beyond the new concrete pedestrian ramps, consistent with the existing trail system along these recreational trails. The trail between Norma Avenue and Indian Oaks Court is very narrow, particularly along the west side of the trail. This trail is proposed to be widened to a standardized 6-ft width throughout, matching the southern edge, and will maintain the existing drainage swale over the trail along the backyard lot lines. The bituminous curb along the west side of the trail, adjacent to 1503 Briarknoll Drive, is proposed to be replaced to continue to manage drainage. Existing handrails along portions of the trails are proposed to remain in place. The modular block retaining wall along the south side of the trail, approximately behind 1479 Colleen Avenue, is also proposed to be replaced and improved as part of the project. See Figure 1 in Appendix A for the proposed project layout identifying the trails to be rehabilitated and the locations of ADA pedestrian ramp improvements. See Figure 3 in Appendix A for the proposed retaining wall and bituminous curb replacements. Prepared by: Bolton & Menk, Inc. PROPOSED IMPROVEMENTS 2024 PMP Street & Utility Improvements I OT1.130168 Page 7