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Mounds View Stormwater Pond Assessment RECOMMENDATIONS July 2023 4.7 10-YEAR IMPLEMENTATION PLAN Table 4.5 presents a 10-year Implementation Plan which shows pond expenditures by year. The table includes annual pond inspections and cleanup, sedimentation surveys and dredging as laid out in Table 4.4, and assessments and improvements to selected ponds and their surrounding areas. Costs include engineering, landscape design, testing, and construction. The annual inspection of ponds is to meet the requirement of the City's MS4 permit, which requires that all stormwater ponds be inspected within the five-year permit cycle. It was estimated that 20% of ponds would be inspected each year. The work involves inspecting the pond for erosion, debris and garbage, and outlet condition and functionality. It is expected that basic cleanup and maintenance would be performed as part of the work. The sedimentation surveys and dredging were described in the previous section and laid out in Table 4.4. Detailed cost estimates for the dredging are provided in Appendix C. These cost estimates have been prepared prior to sediment sampling. Once sampling is completed and disposal methods determined for each pond, then the costs can be revised to better reflect estimated disposal costs. Seven ponds were identified in the initial sediment survey as needing dredging within the next five years. These were grouped geographically to minimize costs and disruption and spaced out annually to level out costs. The actual timing is flexible and can be revised to meet specific City needs or budget constraints. Beyond the initial five-year period, a nominal cost was inserted annually for budgeting purposes for future dredging. This work would be subject to future sediment survey results. As described previously, costs have been provided for upland vegetation assessment and restoration in the areas surrounding the ponds. The timing of this work has been coordinated with the pond dredging. The approach would be to restore the upland vegetation concurrent with or immediately following the dredging operations on each pond. This would save on placing a temporary ground cover in the interim until the restoration is completed. In order to meet this schedule, the vegetation assessment would be completed a year in advance of the restoration. Costs for the assessment assume some level of public engagement and education, along with signage as appropriate. Similar to dredging, the restoration costs have been estimated prior to the assessments. Once the assessments are completed, then the estimated restoration costs can be revised to reflect the proposed work. Based on input from the City, upland vegetation restoration of Silver View Pond was included, with the timing of the work occurring in the near term. Since this work is not tied to dredging, actual timing is flexible and can be moved back to meet City needs or preferences. Costs have also been provided for water quality assessment and restoration. The focus here has been on Silver View Pond. Similar to the upland vegetation restoration, the assessment would be performed a year in advance of the restoration and would include a public engagement component. The timing of the work could likely be coordinated between the two restoration pieces. Beyond Silver View Pond, a nominal cost was inserted for budgeting purposes for future water quality work on other ponds. Also similar to upland vegetation restoration, the restoration costs have been estimated prior to the assessments. Once the assessments are completed, then the estimated restoration costs can be revised to reflect the proposed work. 30